Magnetic disk device and method for stopping write operation

Abstract

A magnetic disk device and a method for stopping a write operation are provided that can improve formatting efficiency. The magnetic disk device according to this embodiment includes: a first disk including a first servo sector and a first data sector; a second disk including a second servo sector and a second data sector; a first head including a first write head and a first read head; a second head including a second write head and a second read head; a first actuator having the first head; a second actuator having the second head; a first controller that stops the write operation of both the first head and the second head based on first data sector position error information demodulated from reading the first data sector; and a second controller that stops the write operation of both the first head and the second head based on second data sector position error information demodulated from reading the second data sector.

Description

[0001] This application claims the benefit of priority based on Japanese Patent Application No. 2021-103295 (filing date: June 22, 2021), the entire contents of which are incorporated herein by reference. Technical Field

[0002] Embodiments of the present invention relate to a magnetic disk device and a method for stopping a write operation. Background Art

[0003] A magnetic disk device includes a magnetic disk (hereinafter sometimes referred to as a disk) and a magnetic head (hereinafter sometimes referred to as a head). When vibration and / or shock are applied to the magnetic disk device's head, the position of the magnetic disk device's head changes. When the head position and head speed, as demodulated by a servo sector, exceed predetermined thresholds, the magnetic disk device stops writing data.

[0004] In recent years, magnetic disk devices with multiple actuators (hereinafter sometimes referred to as split-actuator magnetic disk devices or multi-actuator magnetic disk devices) have been proposed. Split-actuator magnetic disk devices control multiple actuators independently. In split-actuator magnetic disk devices, the position of the head is detected in each actuator, so a predetermined time is required until the write operation stops. Therefore, in split-actuator magnetic disk devices, the threshold value for the head position needs to be set to a large value. Summary of the Invention

[0005] The technical problem to be solved by the embodiments of the present invention is to provide a magnetic disk device and a method for stopping a write operation that can improve formatting efficiency.

[0006] The magnetic disk device according to the present embodiment comprises: a first disk including a first servo sector and a first data sector different from the first servo sector; a second disk including a second servo sector and a second data sector different from the second servo sector; a first head including a first write head for writing data to the first disk and a first read head for reading data from the first disk. head); a second head comprising a second write head for writing data to the second disk and a second read head for reading data from the second disk; a first actuator comprising the first head; a second actuator comprising the second head; a first controller for stopping the writing operation of both the first head and the second head based on first data sector position error information demodulated by the first read head when reading the first data sector; and a second controller for stopping the writing operation of both the first head and the second head based on second data sector position error information demodulated by the second read head when reading the second data sector. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 This is a schematic diagram showing an example of the configuration of the magnetic disk device according to the first embodiment.

[0008] Figure 2 It is a plan view showing an example of the arrangement of the head HD relative to the disk DK.

[0009] Figure 3 This is a schematic diagram showing an example of the structure of a servo sector and a data sector according to the first embodiment.

[0010] Figure 4 This is a schematic diagram showing an example of the structure of a servo sector and a data sector according to the first embodiment.

[0011] Figure 5 This is a schematic diagram showing an example of the structure of a servo sector and a data sector according to the first embodiment.

[0012] Figure 6 This is a schematic diagram showing an example of a demodulation method for demodulating DPES (Data Sector Position Error Information) based on data preambles having different frequencies between adjacent tracks.

[0013] Figure 7 This is a schematic diagram showing an example of a demodulation method for demodulating DPES based on data bursts with different frequencies between adjacent tracks.

[0014] Figure 8 This is a schematic diagram showing an example of a demodulation method for demodulating DPES based on a data null-burst.

[0015] Figure 9 This is a diagram showing an example of timing for demodulating SPES (Servo Sector Position Error Information) and DPES.

[0016] Figure 10 This is a schematic diagram showing an example of a method for determining prohibition of a write operation according to the first embodiment.

[0017] Figure 11 This is a schematic diagram showing an example of a method for determining prohibition of a write operation according to the first embodiment.

[0018] Figure 12 It is a schematic diagram showing an example of a method for determining whether or not the write operation of the plurality of heads HD of the plurality of actuators AC is prohibited.

[0019] Figure 13 This is a block diagram showing an example of the positioning control system SYS of the head HD according to the first embodiment.

[0020] Figure 14 This is a flowchart showing an example of a method for stopping a write operation according to the first embodiment.

[0021] Figure 15 This is a schematic diagram showing an example of the configuration of the magnetic disk device 1 according to the first modification.

[0022] Figure 16 It is a schematic diagram showing an example of the configuration of the magnetic disk device 1 according to the second embodiment.

[0023] Figure 17 This is a flowchart showing an example of a method for stopping a write operation according to the second embodiment.

[0024] Figure 18 This is a schematic diagram showing an example of the configuration of the magnetic disk device 1 according to Modification 2.

[0025] Figure 19 It is a schematic diagram showing an example of the configuration of the magnetic disk device 1 according to the third embodiment.

[0026] Figure 20 It is a plan view showing an example of the arrangement of the head HD relative to the disk DK according to the third embodiment.

[0027] Figure 21 This is a diagram showing an example of the geometric arrangement of the write head WH3 and the two read heads RH30 and RH31 when the read head RH30 is located at the radial position RP0.

[0028] Figure 22This is a diagram showing an example of the geometric arrangement of the write head WH3 and the two read heads RH30 and RH31 when the read head RH30 is located at the radial position ORP.

[0029] Figure 23 This is a schematic diagram showing an example of a demodulation method of SPES and DPES according to the third embodiment.

[0030] Figure 24 It is a schematic diagram showing an example of a servo gate according to the third embodiment.

[0031] Figure 25 This is a flowchart showing an example of a method for stopping a write operation according to the third embodiment.

[0032] Figure 26 This is a schematic diagram showing an example of the configuration of the magnetic disk device 1 according to Modification 3.

[0033] Figure 27 It is a schematic diagram showing an example of the configuration of the magnetic disk device 1 according to the fourth embodiment.

[0034] Figure 28 This is a schematic diagram showing an example of the configuration of the magnetic disk device 1 according to the fourth modification.

[0035] Description of labels

[0036] 1…Disk device, HS…Casing, DK…Disk, 12…Spindle, 13…Spindle motor (SPM), 14…Voice coil motor (VCM), 15…Suspension, 16…Microactuator (MA), HD…Head, AM…Arm, 20…Driver IC, 30…Head amplifier IC, 40…Read / write (R / W) channel, 50…Microprocessor (MPU), 60…Hard disk controller (HDC), 70…Volatile memory, 80…Buffer memory, 90…Non-volatile memory, 170…Shock sensor, 180…Write inhibit detector (unit), 190…Controller communication unit, 700…Host system (host), 130…System controller DETAILED DESCRIPTION

[0037] Hereinafter, embodiments will be described with reference to the accompanying drawings. However, the accompanying drawings are merely examples and do not limit the scope of the invention.

[0038] (First embodiment)

[0039] Figure 11 is a schematic diagram showing an example of the configuration of the magnetic disk device 1 according to Embodiment 1. The first direction Z corresponds to the height (or thickness) direction of the magnetic disk device 1.

[0040] The magnetic disk device 1 includes a housing HS, a head disk assembly (HDA) 10, a driver IC 20, a head amplifier integrated circuit (hereinafter referred to as a head amplifier IC or a preamplifier) ​​30, a volatile memory 70, a buffer memory (cache) 80, a non-volatile memory 90, a vibration sensor 170, a write inhibit detector 180, a controller communication unit 190, and a system controller 130 as a single-chip integrated circuit. In addition, the magnetic disk device 1 is connected to a host system (hereinafter referred to as a host) 700. The magnetic disk device 1 has a plurality of actuators AC, for example, two (actuators AC1 and AC2 described later). In addition, the magnetic disk device 1 may also have three or more actuators AC. The magnetic disk device 1 is capable of independently driving the plurality of actuators AC. The magnetic disk device 1 is, for example, a separate actuator magnetic disk device (or a multi-actuator magnetic disk device) capable of independently driving the plurality of actuators AC.

[0041] The housing HS has a bottom wall HSB. Figure 1 The shell HS is shown as having only a bottom wall HSB, but the shell HS has, for example, a bottom wall HSB, side walls erected along the periphery of the bottom wall HSB and toward the first direction Z, and a cover that closes the opening of the base formed by the bottom wall HSB and the side walls.

[0042] The HDA 10 includes a magnetic disk (hereinafter referred to as a disk) DK, a head HD, a spindle motor (hereinafter sometimes referred to as an SPM) 13 that rotates a spindle 12, an arm AM, an actuator block BK, a voice coil motor (hereinafter referred to as a VCM) 14, a suspension 15, and a microactuator (hereinafter sometimes referred to as a MA) 16. The HDA 10 may not include the MA 16. If the HDA 10 does not include the MA 16, the head HD may be mounted on the arm AM. Figure 1 A cross section of the HDA10 is shown in FIG.

[0043] The SPM 13 is mounted on the bottom wall HSB. The main shaft 12 is mounted at the center of the SPM 13.

[0044] The disk DK has a plurality of disks DK. The disk DK is mounted on the spindle 12 and rotated by the drive of the SPM 13. The disk DK has a surface (or sometimes also referred to as an upper surface) FS and a back surface (or sometimes also referred to as a lower surface) RS on the opposite side of the surface (or upper surface). Hereinafter, the surface (or upper surface) and / or the back surface (or lower surface) may also be referred to as the disk DK. Figure 1In the example shown, disk DK includes disks DK0 and DK1. Alternatively, disk DK may include more than three disks. Disks DK0 and DK1 are mounted on the spindle 12. Disk DK1 is, for example, disposed between disk DK0 and bottom wall HSB. Disk DK0 includes an upper surface FS0 and a lower surface RS0 opposite to upper surface FS0. Alternatively, disk DK0 may include more than two disks. Disk DK1 includes an upper surface FS1 and a lower surface RS1 opposite to upper surface FS1. Alternatively, disk DK1 may include more than two disks. Hereinafter, the direction along the circumference of (the upper and lower surfaces of) disk DK will be referred to as the circumferential direction, and the direction orthogonal to the circumferential direction of (the upper and lower surfaces of) disk DK will be referred to as the radial direction. The radial direction corresponds to the direction toward the inner and outer circumference of (the upper and lower surfaces of) disk DK.

[0045] The head HD includes multiple heads HD. The head HD faces the disk DK. The head HD includes a write head WH for writing data to the disk DK and a read head RH for reading data written to the disk DK. Hereinafter, the process of writing data to the disk DK may be referred to as a "write process," and the process of reading data from the disk DK may be referred to as a "read process." Furthermore, the processes of "recording data in a predetermined recording area," "reading data from a predetermined recording area," "positioning the head HD at a predetermined position on the disk DK," "writing data to a predetermined area on the disk DK," and "reading data from a predetermined area on the disk DK" may be referred to as "access."

[0046] exist Figure 1 In the example shown, the head HD includes heads HD0 and HD1. Head HD0 includes head HD00, which faces the upper surface FS0 of disk DK0, and head HD01, which faces the lower surface RS0 of disk DK0. Head HD0 may include only one head or three or more heads. Head HD0 includes a write head WH0, which writes data to disk DK0, and a read head RH0, which reads data written to disk DK0. Write head WH0 includes write head WH00 and write head WH01. Read head RH0 includes read head RH00 and read head RH01.

[0047] Head HD00 includes a write head WH00 for writing data to upper surface FS0 and a read head RH00 for reading data written to upper surface FS0. Head HD01 includes a write head WH01 for writing data to lower surface RS0 and a read head RH01 for reading data written to lower surface RS0.

[0048] The head HD1 includes a head HD10 facing the upper surface FS1 of the disk DK1 and a head HD11 facing the lower surface RS1 of the disk DK1. Furthermore, the head HD1 may include only one head or three or more heads. The head HD1 includes a write head WH1 for writing data to the disk DK1 and a read head RH1 for reading data written to the disk DK1. The write head WH1 includes a write head WH10 and a write head WH11. The read head RH1 includes a read head RH10 and a read head RH11.

[0049] The head HD10 includes a write head WH10 for writing data to the upper surface FS1 and a read head RH10 for reading data written to the upper surface FS1. The head HD11 includes a write head WH11 for writing data to the lower surface RS1 and a read head RH11 for reading data written to the lower surface RS1.

[0050] The actuator block BK includes a plurality of actuator blocks BK. The actuator block BK is rotatably mounted on a bearing BR vertically provided on the bottom wall HSB. Figure 1 In the example shown, actuator block BK includes actuator blocks BK0 and BK1. Actuator block BK may include only one actuator block or three or more. Actuator blocks BK0 and BK1 are rotatably mounted on bearing BR0, which is vertically mounted on bottom wall HSB. Actuator block BK0 is positioned above actuator block BK1. Actuator block BK1 is located between bottom wall HSB and actuator block BK0.

[0051] The arm AM includes a plurality of arms AM. The arm AM is connected to the actuator block BK. Figure 1 In the example shown, the arm AM includes arms AM0 and AM1. Arm AM0 is positioned above arm AM1. In other words, arm AM1 is positioned between arm AM0 and the bottom wall HSB of the housing HS. Depending on the number of heads HD, the arm AM may include only one arm or three or more arms.

[0052] The arm AM0 includes an arm AM00 located on the upper surface FS0 side of the disk DK0 and an arm AM01 located on the lower surface RS0 side of the disk DK0. The arm AM0 may include only one arm or three or more arms depending on the number of heads HD0. The arm AM0 is connected to the actuator block BK0.

[0053] The arm AM1 includes an arm AM10 located on the upper surface FS1 side of the disk DK1 and an arm AM11 located on the lower surface RS1 side of the disk DK1. The arm AM1 may include only one arm or three or more arms, depending on the number of heads HD1. The arm AM1 is connected to the actuator block BK1.

[0054] The VCM 14 includes a plurality of VCMs 14. The VCM 14 is connected to the actuator block BK on the opposite side of the arm AM. Figure 1 In the example shown, VCM 14 includes VCMs 140 and 141. VCM 144 may include only one VCM or three or more VCMs, depending on the number of actuator blocks BK. VCM 140 is connected to actuator block BK0 on the side opposite to arm AM0. VCM 140 is located above VCM 141. VCM 141 is connected to actuator block BK1 on the side opposite to arm AM1. VCM 141 is located between bottom wall HSB and VCM 140.

[0055] The suspension 15 includes a plurality of suspensions 15. The suspension 15 is mounted on the arm AM. The head HD is mounted on the top end of the suspension 15 on the opposite side to the end connected to the arm AM. Figure 1 In the example shown, the suspension 15 includes suspensions 150 and 151. Suspension 150 is disposed on suspension 151. Suspension 151 is disposed between suspension 150 and bottom wall HSB of housing HS. Suspension 15 may include only one suspension or three or more suspensions depending on the number of arms AM.

[0056] The suspension 150 is mounted on the arm AM0. The suspension 150 is equipped with a head HD0 at the top end on the side opposite to the end connected to the arm AM0. The suspension 150 includes a suspension 1500 mounted on the arm AM00 and a suspension 1501 mounted on the arm AM01. In addition, the suspension 150 may have only one suspension or three or more suspensions depending on the number of arms AM0. The suspension 1500 is equipped with a head HD00 at the top end on the side opposite to the end connected to the arm AM00. The suspension 1501 is equipped with a head HD01 at the top end on the side opposite to the end connected to the arm AM01.

[0057] The suspension 151 is mounted on the arm AM1. The suspension 151 has a head HD1 mounted on the top end opposite to the end connected to the arm AM1. The suspension 151 includes a suspension 1510 mounted on the arm AM10 and a suspension 1511 mounted on the arm AM11. Furthermore, the suspension 151 may have only one suspension or three or more suspensions, depending on the number of arms AM1. The suspension 1510 has a head HD10 mounted on the top end opposite to the end connected to the arm AM10. The suspension 1511 has a head HD11 mounted on the top end opposite to the end connected to the arm AM11.

[0058] The MA 16 includes multiple MAs 16. The MA 16 is mounted on the arm AM, the suspension 15, or the head HD. The MA 16 finely controls the radial motion of the head HD. For example, compared to the radial motion control of the head HD by the VCM 14, the MA 16 controls the radial motion of the head HD more finely.

[0059] exist Figure 1 In the example shown, MA16 includes MA160 and MA161.

[0060] MA160 is mounted on the suspension 150. MA160 finely controls the radial motion of head HD0. For example, compared to the radial motion control of head HD0 by VCM140, MA160 controls the radial motion of head HD0 more finely. For example, MA160 includes MA1600 mounted on suspension 1500 and MA1601 mounted on suspension 1501. Depending on the number of suspensions 150, MA160 can include only one MA or three or more MAs.

[0061] MA1600 finely controls the radial motion of head HD00. For example, MA1600 controls the radial motion of head HD00 more finely than VCM140 controls the radial motion of head HD00. MA1601 finely controls the radial motion of head HD01. For example, MA1601 controls the radial motion of head HD01 more finely than VCM140 controls the radial motion of head HD01.

[0062] The MA161 is mounted on the suspension 151. The MA161 finely controls the radial movement of the head HD1. For example, the MA161 finely controls the radial movement of the head HD1. For example, compared to the radial movement control of the head HD1 by the VCM 141, the MA161 controls the radial movement of the head HD1 more finely. The MA161 includes, for example, the MA1610 mounted on the suspension 1510 and the MA1611 mounted on the suspension 1511. Depending on the number of suspensions 151, the MA161 may include only one MA or three or more MAs.

[0063] The MA 1610 finely controls the radial motion of the head HD10. For example, compared to the control of the radial motion of the head HD10 by the VCM 141, the MA 1610 controls the radial motion of the head HD10 more finely. The MA 1611 finely controls the radial motion of the head HD11. For example, compared to the control of the radial motion of the head HD11 by the VCM 141, the MA 1611 controls the radial motion of the head HD11 more finely.

[0064] The actuator AC includes a plurality of actuators AC. The plurality of actuators AC are mounted on the bearing BR in a manner that allows them to rotate freely (or swivel freely). In other words, the plurality of actuators AC rotate independently around the bearing BR. In addition, the plurality of actuators AC can also rotate in parallel around the bearing BR. The plurality of actuators AC are respectively composed of a VCM14, a suspension 15, an MA16, an arm AM, and an actuator block BK. The plurality of actuators AC drive the VCM14 around the bearing BR and finely drive the MA16, thereby positioning the head HD mounted on the suspension 15 at a predetermined position on the disk DK. In addition, in the absence of the MA16, the plurality of actuators AC drive the VCM14 around the bearing BR, thereby positioning the head HD mounted on the suspension 15 at a predetermined position on the disk DK.

[0065] exist Figure 1 In the example shown, the actuator AC includes actuators AC0 and AC1. Actuator AC0 is arranged above actuator AC1. In other words, actuator AC1 is arranged between bottom wall HSB and actuator AC0. Furthermore, three or more actuators AC may be provided.

[0066] The actuator AC0 is rotatably mounted on the bearing BR0. The actuator AC0 consists of the suspension 150, MA160, arm AM0, actuator block BK0, and VCM140. The actuator AC0 drives the VCM140 around the rotation axis of the bearing BR0 and precisely drives the MA160, thereby positioning the head HD0 mounted on the suspension 150 at a predetermined position on the disk DK0. If the MA160 is not present, the actuator AC0 drives the VCM140 around the bearing BR0 to position the head HD0 mounted on the suspension 150 at a predetermined position on the disk DK0.

[0067] The actuator AC1 is rotatably mounted on the bearing BR0. It consists of the suspension 151, MA161, arm AM1, actuator block BK1, and VCM141. The actuator AC1 drives the VCM141 around the rotation axis of the bearing BR0 and precisely drives the MA161, thereby positioning the head HD1 mounted on the suspension 151 at a predetermined position on the disk DK1. If the MA161 is not present, the actuator AC1 drives the VCM141 around the bearing BR0 to position the head HD1 mounted on the suspension 151 at a predetermined position on the disk DK1.

[0068] Figure 2 1 is a plan view showing an example of the configuration of the head HD relative to the disk DK. Figure 2 As shown, the direction toward the outer periphery of the disk DK in the radial direction is called the outer direction (outer side), and the direction opposite to the outer direction is called the inner direction (inner side). In the circumferential direction, the direction in which the disk DK rotates is called the rotation direction. Figure 2 In the example shown, the rotation direction is shown as counterclockwise, but the opposite direction (clockwise) is also possible. The second direction X and the third direction Y correspond to directions parallel to the upper surface or the lower surface of the disk DK. Viewing toward the XY plane defined by the second direction X and the third direction Y is sometimes referred to as a top view.

[0069] The upper surface FS (FS0, FS1) and lower surface RS (RS0, RS1) of the disk DK (DK0, DK1) are allocated with user data areas DKa (DKa0, DKa1, DKa2, DKa3) that can be used by the user, and system areas DKb (DKb0, DKb1, DKb2, DKb3) for writing information required for system management (hereinafter sometimes referred to as system information) in the areas where data can be written. Hereinafter, the predetermined position in the radial direction of the disk DK may sometimes be referred to as the radial position, and the predetermined position in the circumferential direction of the disk DK may sometimes be referred to as the circumferential position. The radial position and the circumferential position may sometimes be referred to as simply the position. For example, the radial position corresponds to the radial position of a track or sector, and the circumferential position corresponds to the circumferential position of a sector on a predetermined track. For example, the position corresponds to the position of a sector on the disk DK. The location of a sector can be represented by at least one of the cylinder (track) number of the predetermined sector, the head number of the head HD accessing the predetermined sector, the sector number of the predetermined sector, the radial position of the predetermined sector on the disk DK, and the disk angle of the predetermined sector. For example, the location of a sector can be represented by a combination of two of the cylinder (track) number of the predetermined sector, the head number of the head HD accessing the predetermined sector, the sector number of the predetermined sector, the radial position of the predetermined sector on the disk DK, and the disk angle of the predetermined sector. A disk DK can be configured with at least one track. Hereinafter, the term "track" will be used to mean "one of the multiple areas obtained by radially dividing the disk DK," "data written along the circumference of the disk DK," "a path along the circumference of the disk DK," and various other meanings. Tracks adjacent to each other in the radial direction of the disk DK are sometimes referred to as "adjacent tracks." A track includes multiple sectors. The term "sector" is used to mean "one of a plurality of areas obtained by dividing a track in a circumferential direction", "data written to one of a plurality of areas obtained by dividing a track in a circumferential direction", and other various meanings.

[0070] exist Figure 2 In the example shown, the top surface FS0 of disk DK0 is allocated with a user data area DKa0 and a system area DKb0. The bottom surface RS0 of disk DK0 is allocated with a user data area DKa1 and a system area DKb1. The top surface FS1 of disk DK1 is allocated with a user data area DKa2 and a system area DKb2. The bottom surface RS1 of disk DK1 is allocated with a user data area DKa3 and a system area DKb3. When viewed from above, disks DK0 and DK1 overlap.

[0071] The disk DK has a plurality of servo areas (hereinafter sometimes also referred to as servo patterns) SV and a plurality of data areas DTR, not shown. The plurality of servo patterns extend radially in the radial direction of the disk DK and are discretely arranged at predetermined intervals in the circumferential direction. The plurality of data areas are arranged, for example, between servo patterns that are adjacent in the circumferential direction on the disk DK. "Adjacent" naturally includes data, objects, areas, and spaces that are arranged in contact, as well as being arranged at predetermined intervals. Hereinafter, a servo area SV on a predetermined track will sometimes be referred to as a "servo sector." In addition, a servo area SV will sometimes be referred to as a servo sector SV. A servo sector contains servo data. In addition, "servo data written to a servo sector" will sometimes be referred to as a "servo sector." In addition, a sector in a data area DTR on a predetermined track will sometimes be referred to as a "data sector." The data area DTR has a plurality of sectors. In addition, the data area DTR only needs to have one sector. In addition, the data area DTR will sometimes be referred to as a data sector DTR. A data sector contains user data. Data other than servo data written in the user data area DKa outside the servo sector may also be referred to as user data. In addition, "user data written in the data sector" may also be referred to as "data sector".

[0072] When the head HD is seeking, for example, it is rotated around the bearing BR by the actuator AC and slides in the horizontal plane of the disk DK. Figure 2 In the example shown, the head HD1 is rotated about the bearing BR0 by the actuator AC1 and slides on the horizontal surface of the disk DK1, for example, during a seek.

[0073] Figure 3 Schematic diagram showing an example of the structure of the servo sector SS and the data sector DS according to the present embodiment. Figure 3 1 shows a predetermined servo sector SS written in a predetermined track TRn of the disk DK. Figure 3 As shown in FIG, in the circumferential direction, the direction of the front end of the arrow pointing forward is called the front (or front direction), and the direction of the front end of the arrow pointing backward is called the rear (or rear direction). For example, in the circumferential direction, the direction of reading / writing (read / write direction) corresponds to the direction from the front direction to the rear direction. The read / write direction, for example, corresponds to the direction from the front direction to the rear direction. Figure 2 The direction of rotation is opposite to that shown.

[0074] A servo sector SS includes a sector / cylinder, a null burst, and an RRO bit. Alternatively, a servo sector SS may not include an RRO bit. Furthermore, a servo sector SS may include a postcode instead of an RRO bit. In a servo sector SS, the sector / cylinder, null burst, and RRO bit are arranged consecutively in the read / write direction in the order listed.

[0075] The sector / cylinder consists of a preamble, servo mark, Gray code, and PAD. The preamble contains preamble information for synchronizing with the reproduced signal of the servo pattern composed of servo marks and Gray code. The servo mark contains servo mark information indicating the start of the servo pattern. The Gray code consists of the address of a predetermined track (cylinder address) and the address of the servo sector of the predetermined track. The PAD contains PAD information for synchronization signals such as gap and servo AGC.

[0076] The Null pulse train is data (relative position data) used to detect the radial (and / or circumferential) positional deviation (position error) of the head HD relative to a target position (hereinafter sometimes referred to as the target position) on a predetermined track (or predetermined sector), such as the center of the track. The Null pulse train is written with a data pattern whose phase is reversed 180° in the radial direction of the disk DK for each servo track period. A servo track (servo cylinder) corresponds to a track that is the target of a write or read operation based on commands from the host computer 700, etc. The pulse train data is used, for example, to determine the radial and / or circumferential position of the head HD on the disk DK (hereinafter sometimes referred to as the head position). The Null pulse train includes, for example, an N-burst and a Q-burst. The N-burst and Q-burst are written with a data pattern whose phases are offset by 90° in the radial direction of the disk DK.

[0077] The RRObit includes data (hereinafter referred to as RRO correction data) for correcting errors caused by jitter (repetitive runout: RRO) synchronized with the rotation of the disk DK when writing servo data to the disk, such as skew (deformation) of the track relative to the target path of the head HD arranged concentrically with the disk DK (hereinafter sometimes referred to as the target path), for example, at the center of the track. For ease of explanation, errors caused by skew of the track relative to the target path caused by RRO may be referred to simply as RRO.

[0078] The data sector DS is adjacent to the servo sector SS. Figure 3 In the example shown, the data sector DS is adjacent to (or behind) the servo sector SS in the read / write direction. User data is written in the data sector DS.

[0079] A data sector DS includes a preamble, a syncmark, and a data field. In a data sector DS, the preamble, syncmark, and data field are arranged consecutively in the read / write direction in the order in which they are listed. The preamble contains preamble information used to synchronize the reproduced signal of the data sector. Hereinafter, the preamble of a data sector DS may also be referred to as the data preamble. The syncmark contains information indicating the beginning of the data field. Hereinafter, the syncmark of a data sector DS may also be referred to as the data syncmark. The data field corresponds to the area where user data is written (or recorded).

[0080] Figure 4 Schematic diagram showing an example of the structure of the servo sector SS and the data sector DS according to the present embodiment.

[0081] A data sector DS includes a data preamble, a data synchronization mark, a data field, and a burst. In a data sector DS, the preamble, synchronization mark, data field, and burst are arranged consecutively in the read / write direction in the order in which they are listed. The burst is data (relative position data) used to detect the radial and / or circumferential positional deviation (position error) of the head HD relative to the center of a predetermined track. It consists of a repetitive pattern with a predetermined period. Hereinafter, the burst in a data sector DS may also be referred to as a data burst.

[0082] Figure 5 Schematic diagram showing an example of the structure of the servo sector SS and the data sector DS according to the present embodiment.

[0083] A data sector DS includes a data preamble, a data synchronization mark, a data field, and a Null burst. In a data sector DS, the preamble, synchronization mark, data field, and Null burst are arranged consecutively in the read / write direction in the order listed. The Null burst is data (relative position data) used to detect the radial and / or circumferential position deviation (position error) of the head HD relative to the center of a predetermined track. It consists of a pattern repeating at a predetermined period. Hereinafter, the Null burst in a data sector DS may also be referred to as a Data Null Burst. The Data Null burst is written with a data pattern in which the phase of the burst data is reversed 180° in the radial direction of the disk DK for each servo track period. For example, the Data Null burst includes an N burst (hereinafter sometimes referred to as a Data N Burst) and a Q burst (hereinafter sometimes referred to as a Data Q Burst). The Data N burst and the Data Q burst are each written with a pattern in which their phases are shifted by 90° for each period. The data N pulse train and the data Q pulse train are written in a pattern in which the phases of the pulse trains (Burst) adjacent to each other in the circumferential direction are shifted by 180°.

[0084] The driver IC 20 controls the driving of the SPM 13, VCM 14 (VCMs 140 and 141), and / or MA 16 under the control of the system controller 130 (specifically, the MPU 50 or HDC 60 described later). The driver IC 20 is electrically connected to the SPM 13, VCM 14, and MA 16. For example, the driver IC 20 is connected to the SPM 13, VCM 14, and MA 16 via a predetermined interface.

[0085] The driver IC 20 includes an SPM control unit 210, a VCM control unit 220, and a microactuator (MA) control unit 230. The SPM control unit 210 controls the rotation of the SPM 13. The VCM control unit 220 controls the drive of the VCM 14 by controlling the current (or voltage) supplied to the VCM 14. The MA control unit 230 controls the drive of the MA 16 by controlling the current (or voltage) supplied to the MA 16. Furthermore, a portion of the components of the driver IC 20 (e.g., the SPM control unit 210, the VCM control unit 220, and the MA control unit 230) may be provided in the system controller 130. If the actuator AC does not include the MA 16, the MA control unit 230 may also be omitted. Furthermore, the driver IC 20 may not include at least one of the SPM control unit 210, the VCM control unit 220, and the MA control unit 230.

[0086] exist Figure 1In the example shown, the driver IC 20 includes a driver IC 20A and a driver IC 20B. The driver ICs 20A and 20B are formed in separate configurations, such as separate circuits. Alternatively, the driver ICs 20A and 20B may be formed in an integrated configuration, such as an integrated circuit. Depending on the number of actuators AC or heads HD, the driver IC 20 may include only one driver IC or three or more driver ICs. The SPM control unit 210 includes an SPM control unit 210A. Alternatively, the SPM control unit 210 may include only one SPM control unit or two or more SPM control units. The VCM control unit 220 includes VCM control units 220A and 220B. Alternatively, the VCM control unit 220 may include only one VCM control unit or three or more VCM control units. The MA control unit 230 may also include MA control units 230A and 230B. Alternatively, the MA control unit 230 may include only one MA control unit or three or more MA control units.

[0087] The driver IC 20A controls the driving of the SPM 13, VCM 140, and MA 160 under the control of the system controller 130A (specifically, the MPU 50A or HDC 60A described later). The driver IC 20A is electrically connected to the SPM 13, VCM 140, and MA 160. The driver IC 20A is connected to the SPM 13, VCM 140, and MA 160, for example, via a predetermined interface.

[0088] The driver IC 20A includes an SPM control unit 210A, a VCM control unit 220A, and a microactuator (MA) control unit 230A. The SPM control unit 210A controls the rotation of the SPM 13. The VCM control unit 220A controls the drive of the VCM 140 by controlling the current (or voltage) supplied to the VCM 140. The MA control unit 230A controls the drive of the MA 160 by controlling the current (or voltage) supplied to the MA 160. Furthermore, a portion of the components of the driver IC 20A (e.g., the SPM control unit 210A, the VCM control unit 220A, and the MA control unit 230A) may be provided in the system controller 130A. If the actuator AC0 does not include the MA 160, the MA control unit 230A may also be omitted.

[0089] The driver IC 20B controls the driving of the VCM 141 and the MA 161 under the control of the system controller 130B (specifically, the MPU 50B or the HDC 60B described later). The driver IC 20B is electrically connected to the VCM 141 and the MA 161. The driver IC 20B is connected to the VCM 141 and the MA 161 through, for example, a predetermined interface.

[0090] The driver IC 20B includes a VCM control unit 220B and an MA control unit 230B. The VCM control unit 220B controls the current (or voltage) supplied to the VCM 141 to control the driving of the VCM 141. The MA control unit 230B controls the current (or voltage) supplied to the MA 161 to control the driving of the MA 161. Alternatively, a portion of the driver IC 20B components (e.g., the VCM control unit 220B and the MA control unit 230B) may be provided in the system controller 130B. If the actuator AC1 does not include the MA 161, the MA control unit 230B may also be omitted.

[0091] The head amplifier IC (preamplifier) ​​30 amplifies the read signal received from the disk DK and outputs it to the system controller 130 (specifically, the read / write (R / W) channel 40 described later). The head amplifier IC 30 is electrically connected to each head HD, for example, head HD0 and head HD1. Furthermore, the head amplifier IC 30 outputs a write current to the head HD in response to the signal output from the R / W channel 40.

[0092] The head amplifier IC 30 includes a head selector 310 and a read signal detector 320. The head selector 310 selects the read head RH in the actuator AC to read data from the disk DK. The read signal detector 320 detects the signal (read signal) read by the read head RH from the disk DK. Alternatively, a portion of the components of the head amplifier IC 30 (e.g., the head selector 310 and the read signal detector 320) may be provided in the system controller 130.

[0093] exist Figure 1 In the example shown, the head amplifier IC 30 includes a head amplifier IC 30A and a head amplifier IC 30B. The head amplifier IC 30 may include only one head amplifier IC or may include three or more head amplifier ICs. The head amplifier ICs 30A and 30B are formed in separate configurations, such as separate circuits. Alternatively, the head amplifier ICs 30A and 30B may be formed in an integrated configuration, such as an integrated circuit. The read head selection unit 310 includes read head selection units 310A and 310B. Alternatively, the read head selection unit 310 may include only one read head selection unit or may include three or more read head selection units. The read signal detection unit 320 includes read signal detection units 320A and 320B. Alternatively, the read signal detection unit 320 may include only one read signal detection unit or may include three or more read signal detection units.

[0094] The head amplifier IC 30A amplifies the read signal received from disk DK0 and outputs it to the system controller 130A (specifically, the read / write (R / W) channel 40A described later). The head amplifier IC 30A is electrically connected to each head HD0, for example, heads HD00 and HD01. Furthermore, the head amplifier IC 30A outputs a write current to head HD0 in response to the signal output from the R / W channel 40A.

[0095] The head amplifier IC 30A includes a head selector 310A and a read signal detector 320A. The head selector 310A selects the read head RH0 in the actuator AC0 to read data from the disk DK0. The read signal detector 320A detects the signal (read signal) read by the read head RH0 from the disk DK0. Alternatively, a portion of the components of the head amplifier IC 30A (e.g., the head selector 310A and the read signal detector 320A) may be provided in the system controller 130A.

[0096] The head amplifier IC 30B amplifies the read signal received from the disk DK1 and outputs it to the system controller 130B (specifically, the read / write (R / W) channel 40B described later). The head amplifier IC 30B is electrically connected to each head HD1, for example, heads HD10 and HD11. Furthermore, the head amplifier IC 30B outputs a write current to the head HD1 in accordance with the signal output from the R / W channel 40B.

[0097] The head amplifier IC 30B includes a head selector 310B and a read signal detector 320B. The head selector 310B selects the read head RH1 in the actuator AC1, which reads data from the disk DK1. The read signal detector 320B selects the read head RH1, which reads data from the disk DK1. The read signal detector 320B detects the signal (read signal) read by the read head RH1 from the disk DK1. Alternatively, a portion of the components of the head amplifier IC 30B (e.g., the head selector 310B and the read signal detector 320B) may be provided in the system controller 130B.

[0098] Volatile memory 70 is a semiconductor memory that loses stored data when power is disconnected. It stores data required for processing within various components of magnetic disk drive 1. Examples of volatile memory 70 include DRAM (Dynamic Random Access Memory) and SDRAM (Synchronous Dynamic Random Access Memory).

[0099] The buffer memory 80 is a semiconductor memory that temporarily records data exchanged between the magnetic disk drive 1 and the host computer 700. Alternatively, the buffer memory 80 may be integrally formed with the volatile memory 70. Examples of the buffer memory 80 include DRAM, SRAM (Static Random Access Memory), SDRAM, FeRAM (Ferroelectric Random Access Memory), or MRAM (Magnetoresistive Random Access Memory).

[0100] The nonvolatile memory 90 is a semiconductor memory that records stored data even when power is turned off. The nonvolatile memory 90 is, for example, a NOR-type or NAND-type flash ROM (Flash Read Only Memory: FROM).

[0101] The vibration sensor 170 detects vibration and / or impact applied to the magnetic disk device 1 or the housing of the magnetic disk device 1 from the outside. When the vibration sensor 170 detects vibration and / or impact, it outputs a signal indicating that the vibration and / or impact has been detected (hereinafter sometimes referred to as a vibration / impact detection signal). The vibration sensor 170 is electrically connected to, for example, a write inhibit detector 180. When the vibration sensor 170 detects vibration and / or impact, it outputs the vibration / impact detection signal to the write inhibit detector 180.

[0102] The write inhibit detector 180 outputs a signal for determining whether to inhibit writing (or writing operation) (sometimes also referred to as a write inhibit determination execution signal). Upon receiving a vibration / shock detection signal, the write inhibit detector 180 outputs the write inhibit determination execution signal. The write inhibit detector 180 is electrically connected to, for example, the R / W channel 40. Upon receiving a vibration / shock detection signal, the write inhibit detector 180 outputs the write inhibit determination execution signal to the R / W channel 40.

[0103] The controller communication unit 190 controls the transmission (forwarding) of information between the plurality of system controllers 130, for example, the system controllers 130A and 130B described later. The controller communication unit 190 is electrically connected to, for example, the system controllers 130A and 130B. The controller communication unit 190 includes a communication unit 191. The communication unit 191 performs data (information) communication.

[0104] The system controller (controller) 130 is implemented, for example, using a large-scale integrated circuit (LSI) known as a system-on-a-chip (SoC), in which multiple components are integrated on a single chip. The system controller 130 includes a read / write (R / W) channel 40, a microprocessor (MPU) 50, and a hard disk controller (HDC) 60. The system controller 130 is electrically connected to the driver IC 20, the head amplifier IC 30, the volatile memory 70, the buffer memory 80, the non-volatile memory 90, the write inhibit detector 180, the controller communication unit 190, and the host system 700. The system controller 130 may also include an SPM control unit 210, a VCM control unit 220, and an MA control unit 230. The system controller 130 may also include the driver IC 20 and the head amplifier IC 30. Furthermore, two or more system controllers 130 may be provided, corresponding to the number of actuators AC or heads HD.

[0105] The R / W channel 40 performs signal processing for read data transferred from the disk DK to the host 700 and write data transferred from the host 700, based on instructions from the MPU 50 (described later). The R / W channel 40 includes circuitry or functionality for measuring the signal quality of read data. The R / W channel 40 is electrically connected to, for example, the head amplifier IC 30, the MPU 50, the HDC 60, and the write inhibit detector 180. The R / W channel 40 includes a write inhibit unit 410. Furthermore, two or more R / W channels 40 may be provided, corresponding to the number of actuators AC or heads HD.

[0106] The write inhibit unit 410 inhibits (or stops) writing (or writing operations) by the head HD. The write inhibit unit 410 inhibits (or stops) writing (or writing operations) by the head HD via the HDC 60. The write inhibit unit 410 includes a vibration sensor write inhibit determination unit 411, a first HDC write inhibit determination unit 412, and a second HDC write inhibit determination unit 413. Alternatively, the first HDC write inhibit determination unit 412 and the second HDC write inhibit determination unit 413 may be provided in the HDC 60.

[0107] When vibration or impact is detected by the vibration sensor 170, the vibration sensor write prohibition determination unit 411 determines whether to prohibit (or stop) writing (or writing action) performed by the head HD of the predetermined actuator AC or not (determines whether to prohibit (or stop) writing (or writing action) performed by the head HD of the predetermined actuator AC).

[0108] For example, when a write inhibit determination execution signal is received, the vibration sensor write inhibit determination unit 411 selects at least one actuator AC from among multiple actuators AC, and determines whether to determine whether to prohibit (or stop) writing (or writing action) performed by at least one head HD of the selected at least one actuator AC or not.

[0109] For example, when a write inhibit determination execution signal is received, the vibration sensor write inhibit determination unit 411 selects at least one head HD from among a plurality of heads HD, and determines whether to determine whether to prohibit (or stop) writing (or writing action) performed by the selected at least one head HD or not to determine whether to prohibit (or stop) writing (or writing action).

[0110] For example, when receiving the write inhibit determination execution signal, the vibration sensor write inhibit determination unit 411 determines whether the vibration or shock is larger than a predetermined value based on the write inhibit determination execution signal.

[0111] For example, when it is determined that the vibration or impact is greater than a predetermined value, the vibration sensor write prohibition determination unit 411 selects at least one actuator AC from multiple actuators AC and determines whether the writing (or writing action) performed by at least one head HD of the selected at least one actuator AC is prohibited (or stopped).

[0112] For example, when it is determined that the vibration or impact is greater than a predetermined value, the vibration sensor write prohibition determination unit 411 selects at least one actuator AC from multiple actuators AC, and outputs a signal or information (hereinafter sometimes also referred to as a write prohibition determination signal or write prohibition determination information) indicating the prohibition (or stop) of writing (or writing action) performed by at least one head HD of the selected at least one actuator AC to the HDC60 corresponding to the head HD of the selected predetermined actuator AC.

[0113] For example, when determining that the vibration or shock is equal to or less than a predetermined value, the vibration sensor write inhibit determination unit 411 does not determine the inhibition (or stop) of writing (or writing operation) by the head HD of the predetermined actuator AC.

[0114] For example, when it is determined that the vibration or impact is greater than a predetermined value, the vibration sensor write prohibition determination unit 411 selects at least one head HD from among the multiple heads HD and determines whether to prohibit (or stop) writing (or writing action) performed by the selected at least one head HD.

[0115] For example, when it is determined that the vibration or impact is greater than a predetermined value, the vibration sensor write inhibit determination unit 411 selects at least one head HD from a plurality of heads HD, and outputs a write inhibit determination signal (or write inhibit determination information) for determining whether writing (or writing action) performed by the selected at least one head HD is prohibited (or stopped) to the HDC60 corresponding to the head HD of the selected predetermined actuator AC.

[0116] For example, when it is determined that the vibration or shock is equal to or less than a predetermined value, the vibration sensor write inhibition determination unit 411 does not determine the inhibition (or stop) of writing (or writing operation) by the predetermined head HD.

[0117] The first HDC write inhibit determination unit 412 inhibits (or stops) writing (or a writing operation) to a predetermined head HD corresponding to a predetermined HDC 60. For example, upon receiving a signal (hereinafter sometimes referred to as a write inhibit signal) from the predetermined HDC 60 to inhibit (or stop) writing (or a writing operation) to the predetermined head HD corresponding to the predetermined HDC 60, the first HDC write inhibit determination unit 412 negates or deasserts a write gate, thereby inhibiting (or stopping) writing (or a writing operation) to the predetermined head HD corresponding to the predetermined HDC 60. In other words, when receiving a write inhibit signal from the predetermined HDC60 that prohibits (or stops) writing (or writing action) to the predetermined head HD corresponding to the predetermined HDC60 and information indicating that the predetermined head HD corresponding to the predetermined HDC60 is subjected to vibration (hereinafter sometimes also referred to as vibration detection information), the first HDC write inhibit determination unit 412 invalidates (negates or deasserts) the write gate and prohibits (or stops) writing (or writing action) to the predetermined head HD corresponding to the predetermined HDC60.

[0118] For example, upon receiving a write inhibit signal for writing (or a write operation) to a predetermined head HD corresponding to an HDC (hereinafter sometimes referred to as another HDC) 60 other than the HDC 60 corresponding to the first HDC write inhibit determination unit 412, the first HDC write inhibit determination unit 412 negates (negates or deasserts) a write gate, thereby inhibiting (or stopping) writing (or a write operation) to the predetermined head HD corresponding to the predetermined HDC 60. In other words, upon receiving vibration detection information including a write inhibit signal for inhibiting (or stopping) writing (or a write operation) to the predetermined head HD corresponding to the other HDC 60 and indicating that the predetermined head HD corresponding to the other HDC 60 is vibrating, the first HDC write inhibit determination unit 412 negates (negates or deasserts) a write gate, thereby inhibiting (or stopping) writing (or a write operation) to the predetermined head HD corresponding to the predetermined HDC 60.

[0119] For example, upon receiving a write inhibit signal that inhibits (or stops) writing (or a write operation) to a predetermined head HD corresponding to another HDC 60, the first HDC write inhibit determination unit 412 outputs the write inhibit signal to the first HDC write inhibit determination unit 412 corresponding to the predetermined HDC 60 via the other HDC 60, thereby inhibiting (or stopping) writing (or a write operation) to the head HD corresponding to the predetermined HDC 60. In other words, upon receiving vibration detection information including a write inhibit signal that inhibits (or stops) writing (or a write operation) to a predetermined head HD corresponding to another HDC 60 and indicating that the predetermined head HD corresponding to the predetermined HDC 60 is vibrating, the first HDC write inhibit determination unit 412 outputs the vibration detection information to the first HDC write inhibit determination unit 412 corresponding to the predetermined HDC 60 via the other HDC 60, thereby inhibiting (or stopping) writing (or a write operation) to the head HD corresponding to the predetermined HDC 60.

[0120] For example, when receiving a write inhibit signal that prohibits (or stops) writing (or writing action) to a predetermined head HD corresponding to another HDC60, the first HDC write inhibit determination unit 412 outputs a signal that prohibits (or stops) writing (or writing action) to the predetermined head HD corresponding to the predetermined HDC60 to the other HDC60, and outputs the write inhibit signal to the first HDC write inhibit determination unit 412 corresponding to the predetermined HDC60 via the other HDC60, thereby prohibiting (or stopping) writing (or writing action) to the predetermined head HD corresponding to the predetermined HDC60. In other words, when receiving a write inhibit signal that prohibits (or stops) writing (or writing action) to a predetermined head HD corresponding to other HDC60 and vibration detection information indicating that the predetermined head HD corresponding to other HDC60 is subjected to vibration, the first HDC write inhibit determination unit 412 outputs a signal that prohibits (or stops) writing (or writing action) to the predetermined head HD corresponding to other HDC60 to the other HDC60, and outputs the vibration detection information to the first HDC write inhibit determination unit 412 corresponding to the predetermined HDC60 via the other HDC60, thereby prohibiting (or stopping) writing (or writing action) to the predetermined head HD corresponding to the predetermined HDC60.

[0121] Furthermore, upon receiving a write inhibit signal for inhibiting (or stopping) writing (or a writing operation) to a predetermined head HD corresponding to another HDC 60, the first HDC write inhibit determination unit 412 may output the write inhibit signal to the first HDC write inhibit determination unit 412 corresponding to the predetermined HDC 60 via the predetermined HDC 60, thereby inhibiting (or stopping) writing (or a writing operation) to the head HD corresponding to the predetermined HDC 60. In other words, upon receiving vibration detection information including a write inhibit signal for inhibiting (or stopping) writing (or a writing operation) to a predetermined head HD corresponding to another HDC 60 and indicating that the predetermined head HD corresponding to the other HDC 60 is vibrating, the first HDC write inhibit determination unit 412 may output the vibration detection information to the first HDC write inhibit determination unit 412 corresponding to the predetermined HDC 60 via the predetermined HDC 60, thereby inhibiting (or stopping) writing (or a writing operation) to the head HD corresponding to the predetermined HDC 60.

[0122] The second HDC write inhibit determination unit 413 inhibits (or stops) writing to (or the writing operation of) a predetermined head HD corresponding to another HDC 60. For example, upon receiving a write inhibit signal from another HDC 60 that inhibits (or stops) writing to (or the writing operation of) a predetermined head HD corresponding to the other HDC 60, the second HDC write inhibit determination unit 413 negates (negates or deasserts) a write gate, thereby inhibiting (or stopping) writing to (or the writing operation of) the predetermined head HD corresponding to the other HDC 60. In other words, upon receiving a write inhibit signal from another HDC 60 that inhibits (or stops) writing to (or the writing operation of) the predetermined head HD corresponding to the other HDC 60 and vibration detection information indicating that the predetermined head HD corresponding to the other HDC 60 is vibrating, the second HDC write inhibit determination unit 413 negates (negates or deasserts) a write gate, thereby inhibiting (or stopping) writing to (or the writing operation of) the predetermined head HD corresponding to the other HDC 60.

[0123] For example, upon receiving a write inhibit signal that inhibits (or stops) writing (or a write operation) to a predetermined head HD corresponding to a predetermined HDC 60, the second HDC write inhibit determination unit 413 negates or deasserts a write gate, thereby inhibiting (or stopping) writing (or a write operation) to predetermined heads HD corresponding to other HDCs 60. In other words, upon receiving vibration detection information including a write inhibit signal that inhibits (or stops) writing (or a write operation) to a predetermined head HD corresponding to a predetermined HDC 60 and indicating that the predetermined head corresponding to the predetermined HDC 60 is vibrating, the second HDC write inhibit determination unit 413 negates or deasserts a write gate, thereby inhibiting (or stopping) writing (or a write operation) to predetermined heads HD corresponding to other HDCs 60.

[0124] For example, upon receiving a write inhibit signal that inhibits (or stops) writing (or a write operation) to the head HD corresponding to a predetermined HDC 60, the second HDC write inhibit determination unit 413 outputs the write inhibit signal to the second HDC write inhibit determination unit 413 corresponding to another HDC 60 via the predetermined HDC 60, thereby inhibiting (or stopping) writing (or a write operation) to the predetermined head HD corresponding to the other HDC 60. In other words, upon receiving vibration detection information including a write inhibit signal that inhibits (or stops) writing (or a write operation) to the head HD corresponding to the predetermined HDC 60 and indicating that the predetermined head HD corresponding to the predetermined HDC 60 is vibrating, the second HDC write inhibit determination unit 413 outputs the vibration detection information to the second HDC write inhibit determination unit 413 corresponding to the other HDC 60 via the predetermined HDC 60, thereby inhibiting (or stopping) writing (or a write operation) to the predetermined head HD corresponding to the other HDC 60.

[0125] For example, when receiving a write inhibit signal that prohibits (or stops) writing (or writing action) to the head HD corresponding to the predetermined HDC60, the second HDC write inhibit determination unit 413 outputs a signal that prohibits (or stops) writing (or writing action) to the predetermined head HD corresponding to other HDC60 to the predetermined HDC60, and outputs the write inhibit signal to the second HDC write inhibit determination unit 413 corresponding to the other HDC60 via the predetermined HDC60, thereby prohibiting (or stopping) writing (or writing action) to the predetermined head HD corresponding to the other HDC60. In other words, when receiving a write inhibit signal that prohibits (or stops) writing (or writing action) to the head HD corresponding to the predetermined HDC60 and vibration detection information indicating that the predetermined head HD corresponding to the predetermined HDC60 is subjected to vibration, the second HDC write inhibit determination unit 413 outputs a signal that prohibits (or stops) writing (or writing action) to the predetermined head HD corresponding to other HDC60 to the predetermined HDC60, and outputs the vibration detection information to the second HDC write inhibit determination unit 413 corresponding to the other HDC60 via the predetermined HDC60, thereby prohibiting (or stopping) writing (or writing action) to the predetermined head HD corresponding to the other HDC60.

[0126] Furthermore, upon receiving a write inhibit signal for inhibiting (or stopping) writing (or a writing operation) to a predetermined head HD corresponding to a predetermined HDC 60, the second HDC write inhibit determination unit 413 may output the write inhibit signal to the second HDC write inhibit determination unit 413 corresponding to the other HDC 60 via another HDC 60, thereby inhibiting (or stopping) writing (or a writing operation) to the head HD corresponding to the other HDC 60. In other words, upon receiving vibration detection information including a write inhibit signal for inhibiting (or stopping) writing (or a writing operation) to the predetermined head HD corresponding to the predetermined HDC 60, indicating that the predetermined head HD corresponding to the predetermined HDC 60 has been subjected to vibration, the second HDC write inhibit determination unit 413 may output the vibration detection information to the second HDC write inhibit determination unit 413 corresponding to the other HDC 60 via another HDC 60, thereby inhibiting (or stopping) writing (or a writing operation) to the head HD corresponding to the other HDC 60.

[0127] The MPU 50 is a main controller that controls the various parts of the magnetic disk device 1 according to instructions from the host computer 700, etc. The MPU 50 controls the actuator AC and / or MA16 via the driver IC 20 to perform servo control for positioning the head HD. The MPU 50 controls the writing of data to the disk DK and selects the storage destination of the written data. In addition, the MPU 50 controls the reading (or reading) of data from the disk DK and controls the processing of the read data. The MPU 50 is connected to the various parts of the magnetic disk device 1. For example, the MPU 50 is electrically connected to the driver IC 20, the R / W channel 40, and the HDC 60. In addition, two or more MPUs 50 may be provided according to the number of actuators AC or heads HD.

[0128] The MPU 50 seeks the head HD to a predetermined radial position of a predetermined circumferential position on the disk DK. The MPU 50 positions the head HD at the predetermined radial position and writes data to a predetermined sector (data sector) or reads data from a predetermined sector (data sector). Hereinafter, "positioning or configuring the center of the head HD (write head WH or read head RH) at a predetermined position" may sometimes be simply expressed as "positioning or configuring the head HD (write head WH or read head RH) at a predetermined position." For example, the MPU 50 positions the head HD at a target position, such as the center of a track, and writes data to a predetermined sector (data sector) or reads data from a predetermined sector (data sector). In addition, MPU50 can write data in either Shingled Write Magnetic Recording (SMR or Shingled Write Recording: SWR) or Conventional Magnetic Recording (CMR). The Shingled Recording method is a recording method in which a part of a predetermined track in the radial direction is written overlappingly with the next track to be written. The Conventional Recording method is a recording method in which tracks adjacent to the predetermined track in the radial direction (hereinafter sometimes also referred to as adjacent tracks) are written at predetermined intervals in the radial direction from the predetermined track.

[0129] The HDC 60 controls read / write processing based on instructions from the MPU 50, and controls data transmission between the host computer 700 and the R / W channel 40. The HDC 60 is electrically connected to, for example, the R / W channel 40, the MPU 50, the volatile memory 70, the buffer memory 80, and the non-volatile memory 90. Furthermore, two or more HDCs 60 may be provided depending on the number of actuators AC or heads HD.

[0130] The HDC60 includes a servo control unit 610 and a write operation determination unit 620. The HDC60 executes the processing of each of the aforementioned units, such as the servo control unit 610 and the write operation determination unit 620, in firmware. Alternatively, the HDC60 may include each of the aforementioned units as circuits. Furthermore, a portion of the HDC60 configuration may be provided within the MPU 50. For example, the servo control unit 610 and the write operation determination unit 620 may also be provided within the MPU 50. The HDC60 prohibits (or stops) the write operation of the HD head. For example, upon receiving a write prohibition signal, the HDC60 prohibits (or stops) the write operation of the HD head at a predetermined timing.

[0131] The servo control unit 610 controls the position of the head HD. In other words, the servo control unit 610 controls access by the head HD to a predetermined area of ​​the disk DK. The servo control unit 610 includes a tracking control unit 611 and a seek control unit 612. Furthermore, two or more servo control units 610 may be provided, corresponding to the number of actuators AC or heads HD.

[0132] The tracking control unit 611 controls the head HD to track a predetermined track of the disk DK. Sometimes, "tracking the head HD on a predetermined track of the disk DK" is simply referred to as "tracking." "Tracking" includes "following a predetermined path, such as a predetermined track, when writing data to the disk DK" and "following a predetermined path, such as a predetermined track, when reading data from the disk DK." The tracking control unit 611 has a DPES demodulation unit 6111. In addition, the tracking control unit 611 may also have an SPES demodulation unit. For example, the SPES demodulation unit demodulates the position error (servo sector position error signal: SPES) demodulated by reading from the servo sector SS of the disk DK.

[0133] The DPES demodulation unit 6111 demodulates the position error (position error information or position error signal) (data sector position error signal: DPES) read and demodulated from the data sector DS.

[0134] The seek control unit 612 controls the head HD to seek from a predetermined track to a target track on the disk DK.

[0135] The write operation determination unit 620 determines the write operation. The write operation determination unit 620 includes a position write operation determination unit 621 and a speed write operation determination unit 622. The position write operation determination unit 621 determines the write operation of the head HD based on the position of the head HD. The speed write operation determination unit 622 determines the write operation of the head HD based on the speed of the head HD.

[0136] The write operation determination section 620 determines whether or not writing (or writing operation) by a predetermined head HD corresponding to a predetermined HDC 60 is prohibited (or stopped).

[0137] For example, when receiving a write prohibition determination signal (or write prohibition determination information) for writing (or writing action) of the predetermined head HD corresponding to the predetermined HDC60, the write action determination unit 620 determines whether to prohibit (or stop) writing (or writing action) of the predetermined head HD corresponding to the predetermined HDC60 based on the SPES demodulated by reading from the servo sector SS of the disk DK by the predetermined head HD corresponding to the predetermined HDC60, or the DPES demodulated by reading from the data sector DS.

[0138] For example, when receiving a write inhibit determination signal (or write inhibit determination information) for writing (or writing action) of a predetermined head HD corresponding to a predetermined HDC60, the write action determination unit 620 determines whether the SPES or DPES corresponding to the predetermined head HD associated with the predetermined HDC60 exceeds a threshold.

[0139] For example, when determining that the SPES or DPES corresponding to the predetermined head HD associated with the predetermined HDC 60 exceeds the threshold, the write operation determination unit 620 outputs a write inhibit signal to the predetermined R / W channel 40 corresponding to the predetermined HDC 60 .

[0140] For example, when receiving a signal from the second HDC write inhibit determination unit 413 corresponding to a predetermined HDC 60 to inhibit writing (or a write operation) to a predetermined head HD corresponding to another HDC 60, the write operation determination unit 620 may output the write inhibit signal to a predetermined R / W channel (hereinafter sometimes referred to as another R / W channel) 40 corresponding to the other HDC 60. For example, when receiving a signal from the second HDC write inhibit determination unit 413 corresponding to a predetermined HDC 60 to inhibit writing (or a write operation) to a predetermined head HD corresponding to another HDC 60, the write operation determination unit 620 may output the write inhibit signal to the other R / W channel 40 via a transmission path including a physical wiring, a communication circuit, or a conceptual path for transmitting or transferring electricity, data, and information.

[0141] In addition, when a signal is received from the second HDC write prohibition determination unit 413 corresponding to the predetermined HDC60 to prohibit writing (or writing action) to the predetermined head HD corresponding to other HDC60, the write action determination unit 620 may also not output a write prohibition signal to other R / W channels 40 based on the status of the predetermined system controller 130 (hereinafter sometimes also referred to as other system controller 130) corresponding to the other HDC60, the predetermined head HD corresponding to the other HDC60, etc.

[0142] For example, when it is determined that the SPES or DPES corresponding to the predetermined head HD associated with the predetermined HDC60 exceeds the threshold, the write action determination unit 620 may also determine to prohibit (or stop) the writing (or writing action) of the predetermined head HD corresponding to the predetermined HDC60, and output the write prohibition signal to other R / W channels 40.

[0143] For example, when it is determined that the SPES or DPES corresponding to the predetermined head HD associated with the predetermined HDC 60 is below the threshold, the write operation determination unit 620 prohibits (or stops) writing (or writing operation) by the predetermined head HD corresponding to the predetermined HDC 60 without passing through the predetermined HDC 60. In other words, when it is determined that the SPES or DPES corresponding to the predetermined head HD associated with the predetermined HDC 60 is below the threshold, the write operation determination unit 620 continues (or continues) writing (or writing operation) by the predetermined head HD corresponding to the predetermined HDC 60 through the predetermined HDC 60.

[0144] The write operation determination unit 620 determines whether or not to prohibit (or stop) writing (or writing operation) of a predetermined head HD corresponding to another HDC 60 .

[0145] For example, when a write inhibit determination signal (or write inhibit determination information) is received to inhibit (or stop) writing (or writing action) of a predetermined head HD corresponding to another HDC60, the write action determination unit 620 determines whether to inhibit (or stop) writing (or writing action) of a predetermined head HD corresponding to another HDC60 based on the SPES demodulated by reading from the servo sector SS of the disk DK by the predetermined head HD corresponding to the other HDC60, or the DPES demodulated by reading from the data sector DS.

[0146] For example, when receiving a write inhibit determination signal (or write inhibit determination information) that inhibits (or stops) writing (or writing action) to a predetermined head HD corresponding to another HDC60, the write action determination unit 620 determines whether the SPES or DPES corresponding to the predetermined head HD associated with the other HDC60 exceeds the threshold.

[0147] For example, when it is determined that the SPES or DPES corresponding to the predetermined head HD associated with other HDC60 exceeds the threshold, the write action determination unit 620 determines to prohibit (or stop) the writing (or writing action) of the predetermined head HD corresponding to the other HDC60, and outputs the write prohibition signal to the predetermined R / W channel 40 corresponding to the other HDC60.

[0148] For example, when receiving a signal prohibiting writing (or writing action) of a predetermined head HD corresponding to a predetermined HDC60 from the first HDC write prohibition determination unit 412 corresponding to another HDC60, the write action determination unit 620 may also output a write prohibition signal to the predetermined R / W channel 40 corresponding to the predetermined HDC60.

[0149] For example, when a signal is received from the first HDC write inhibit determination unit 412 corresponding to other HDC60 to inhibit writing (or writing action) of a predetermined head HD corresponding to a predetermined HDC60, the write action determination unit 620 may also output a write inhibit signal to a predetermined R / W channel 40 via a transmission path including physical wiring, communication circuits, or conceptual paths for transmitting or transferring electricity, data, and information.

[0150] In addition, when a signal is received from the first HDC write prohibition determination unit 412 corresponding to other HDC60 to prohibit writing (or writing action) of the predetermined head HD corresponding to the predetermined HDC60, the write action determination unit 620 may also not output a write prohibition signal to the predetermined R / W channel 40 based on the status of the predetermined system controller 130 corresponding to the predetermined HDC60, the predetermined head HD corresponding to the predetermined HDC60, etc.

[0151] For example, when determining that the SPES or DPES corresponding to a predetermined head HD associated with another HDC 60 exceeds a threshold value, the write operation determination unit 620 may output a write inhibit signal to a predetermined R / W channel 40 .

[0152] For example, when it is determined that the SPES or DPES corresponding to a predetermined head HD associated with another HDC 60 is below a threshold value, the write operation determination unit 620 prohibits (or stops) writing (or a write operation) by the predetermined head HD corresponding to the other HDC 60 without passing through the other HDC 60. In other words, when it is determined that the SPES or DPES corresponding to a predetermined head HD associated with another HDC 60 is below a threshold value, the write operation determination unit 620 continues (or continues) writing (or a write operation) by the predetermined head HD corresponding to the predetermined HDC 60 through the other HDC 60.

[0153] The system controller 130 includes system controllers 130A and 130B. The system controller 130 may include only one system controller or three or more system controllers. The system controllers 130A and 130B may be implemented as separate components, such as separate circuits. Alternatively, the system controllers 130A and 130B may be implemented as an integrated component, such as an integrated circuit.

[0154] The R / W channel 40 includes R / W channels 40A and 40B. Furthermore, the R / W channel 40 may have only one R / W channel or more than three R / W channels. The vibration sensor write inhibit determination unit 411 includes vibration sensor write inhibit determination units 411A and 411B. Furthermore, the vibration sensor write inhibit determination unit 411 may have only one vibration sensor write inhibit determination unit or more than three vibration sensor write inhibit determination units. The first HDC write inhibit determination unit 412 includes first HDC write inhibit determination units 412A and 412B. Furthermore, the first HDC write inhibit determination unit 412 may have only one first HDC write inhibit determination unit or more than three first HDC write inhibit determination units. The second HDC write inhibit determination unit 413 includes second HDC write inhibit determination units 413A and 413B. Furthermore, the second HDC write inhibit determination unit 413 may include only one second HDC write inhibit determination unit, or may include three or more second HDC write inhibit determination units.

[0155] MPU50 includes MPU50A and 50B. HDC60 includes HDC60A and 60B. In addition, HDC60 may have only one HDC or more than three HDCs. Servo control unit 610 includes servo control units 610A and 610B. In addition, servo control unit 610 may have only one servo control unit or more than three servo control units. Tracking control unit 611 includes tracking control units 611A and 611B. In addition, tracking control unit 611 may have only one tracking control unit or more than three tracking control units. DPES demodulation unit 6111 includes DPES demodulation units 6111A and 6111B. DPES demodulation unit 6111 may have only one DPES demodulation unit or more than three DPES demodulation units. Tracking control unit 612 includes tracking control units 612A and 612B. The seek control unit 612 may have only one seek control unit or more than three seek control units. The write action determination unit 620 includes write action determination units 620A and 620B. The write action determination unit 620 may have only one write action determination unit or more than three write action determination units. The position write action determination unit 621 includes position write action determination units 621A and 621B. The position write action determination unit 621 may have only one position write action determination unit or more than three position write action determination units. The speed write action determination unit 622 includes speed write action determination units 622A and 622B. The speed write action determination unit 622 may have only one speed write action determination unit or more than three speed write action determination units.

[0156] The system controller 130A includes an R / W channel 40A, an MPU 50A, and an HDC 60A. The system controller 130A is electrically connected to the driver IC 20A, the head amplifier IC 30A, the volatile memory 70, the buffer memory 80, the non-volatile memory 90, the write inhibit detector 180, the controller communication unit 190, and the host system 700. The system controller 130A is electrically connected to the system controller 130B via transmission paths WR0 and WR1. The transmission paths WR0 and WR1 can be physical wiring, communication circuits, or conceptual pathways for transmitting or transferring electricity, data, and information. The system controller 130A may also include an SPM control unit 210A, a VCM control unit 220A, and an MA control unit 230A. The system controller 130A may also include the driver IC 20A and the head amplifier IC 30A.

[0157] The R / W channel 40A performs signal processing for read data transferred from the disk DK0 to the host computer 700 and for write data transferred from the host computer 700, based on instructions from the MPU 50A. The R / W channel 40A is electrically connected to, for example, the head amplifier IC 30A, the MPU 50A, the HDC 60A, and the write inhibit detector 180. The R / W channel 40A is connected to the write operation determination unit 620B (HDC 60B) via the transmission path WR1. Alternatively, the R / W channel 40A may not be connected to the write operation determination unit 620B (HDC 60B) via the transmission path WR1. The R / W channel 40A includes a write inhibit unit 410A.

[0158] The write inhibit unit 410A inhibits (or stops) writing (or writing operations) by the heads HD0 and HD1 via the HDCs 60A and 60B. The write inhibit unit 410A is connected to the write operation determination unit 620B (HDC 60B) via the transmission path WR1. Alternatively, the write inhibit unit 410A may not be connected to the write operation determination unit 620B (HDC 60B) via the transmission path WR1. The write inhibit unit 410A includes a vibration sensor write inhibit determination unit 411A, a first HDC write inhibit determination unit 412A, and a second HDC write inhibit determination unit 413A.

[0159] When vibration or impact is detected by the vibration sensor 170, the vibration sensor write prohibition determination unit 411A determines whether to prohibit (or stop) writing (or writing action) performed by the head HD0 of the actuator AC0 or not.

[0160] For example, when a write inhibit determination execution signal is received, the vibration sensor write inhibit determination unit 411A determines whether to prohibit (or stop) writing (or writing action) performed by at least one head HD corresponding to the actuator AC0 or not to prohibit (or stop) writing (or writing action).

[0161] For example, upon receiving a write inhibit determination execution signal, the vibration sensor write inhibit determination unit 411A determines whether the vibration or shock is greater than a predetermined value based on the write inhibit determination execution signal. For example, if the vibration or shock is determined to be greater than the predetermined value, the vibration sensor write inhibit determination unit 411A determines to inhibit (or stop) writing (or a write operation) to the at least one head HD0 of the actuator AC0. For example, if the vibration or shock is determined to be greater than the predetermined value, the vibration sensor write inhibit determination unit 411A outputs a write inhibit determination signal indicating that writing (or a write operation) to the at least one head HD0 of the actuator AC0 is prohibited (or stopped). For example, if the vibration or shock is determined to be below the predetermined value, the vibration sensor write inhibit determination unit 411A does not determine to inhibit (or stop) writing (or a write operation) to the at least one head HD0 of the actuator AC0.

[0162] The first HDC write inhibit determination unit 412A inhibits (or stops) writing (or the writing operation) to the head HD0 corresponding to the HDC 60A. For example, upon receiving a write inhibit signal from the HDC 60A to inhibit (or stop) writing (or the writing operation) to the head HD0, the first HDC write inhibit determination unit 412A negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or the writing operation) to the head HD0. In other words, upon receiving a write inhibit signal from the HDC 60A to inhibit (or stop) writing (or the writing operation) to the head HD0 and vibration detection information indicating that the head HD0 is vibrating, the first HDC write inhibit determination unit 412A negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or the writing operation) to the head HD0.

[0163] For example, upon receiving a write inhibit signal that inhibits (or stops) writing (or a write operation) to head HD1 corresponding to HDC 60B, first HDC write inhibit determination unit 412A negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or a write operation) to head HD0. In other words, upon receiving vibration detection information including a write inhibit signal that inhibits (or stops) writing (or a write operation) to head HD1 and indicating that head HD1 is vibrating, first HDC write inhibit determination unit 412A negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or a write operation) to head HD0.

[0164] The second HDC write inhibit determination unit 413A inhibits (or stops) writing (or the writing operation) of the head HD1 corresponding to the HDC 60B. For example, upon receiving a write inhibit signal from the HDC 60A to inhibit (or stop) writing (or the writing operation) of the head HD1, the second HDC write inhibit determination unit 413A outputs the write inhibit signal to the second HDC write inhibit determination unit 413B of the R / W channel 40B via the HDC 60A and the transmission path WR0. The second HDC write inhibit determination unit 413B then negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or the writing operation) of the head HD1. In other words, when receiving a write inhibit signal including a signal for inhibiting (or stopping) writing (or writing action) of the head HD1 from the HDC60A and vibration detection information indicating that the head HD1 is subjected to vibration, the second HDC write inhibit determination unit 413A outputs the vibration detection information to the second HDC write inhibit determination unit 413B of the R / W channel 40B via the HDC60A and the transmission path WR0, and invalidates (negates or deasserts) the write enable via the second HDC write inhibit determination unit 413B, thereby inhibiting (or stopping) writing (or writing action) of the head HD1.

[0165] For example, when a write inhibit signal is received from HDC60A to inhibit (or stop) writing (or writing action) of head HD1, the second HDC write inhibit determination unit 413A outputs the signal to inhibit writing (or writing action) of head HD1 to HDC60A, and outputs the write inhibit signal to the second HDC write inhibit determination unit 413B of the R / W channel 40B via HDC60A and the transmission path WR0, and the write enable is invalidated (negate or deassert) via the second HDC write inhibit determination unit 413B, thereby inhibiting (or stopping) writing (or writing action) of head HD1. In other words, when receiving a write inhibit signal including a signal for inhibiting (or stopping) writing (or writing action) of the head HD1 from the HDC60A and vibration detection information indicating that the head HD1 is subjected to vibration, the second HDC write inhibit determination unit 413A outputs a signal for inhibiting writing (or writing action) of the head HD1 to the HDC60A, outputs the vibration detection information to the second HDC write inhibit determination unit 413B of the R / W channel 40B via the HDC60A and the transmission path WR0, and invalidates (negates or deasserts) the write enable via the second HDC write inhibit determination unit 413B, thereby inhibiting (or stopping) writing (or writing action) of the head HD1.

[0166] For example, when a write inhibit signal is received from HDC60A to inhibit (or stop) writing (or writing action) of head HD1, the second HDC write inhibit determination unit 413A outputs the write inhibit signal to the second HDC write inhibit determination unit 413B of the R / W channel 40B via the transmission path WR1 and HDC60B, and the write enable is invalidated (negate or deassert) via the second HDC write inhibit determination unit 413B, thereby inhibiting (or stopping) writing (or writing action) of head HD1. In other words, when receiving a write inhibit signal including a signal for inhibiting (or stopping) writing (or writing action) of the head HD1 from the HDC60A and vibration detection information indicating that the head HD1 is subjected to vibration, the second HDC write inhibit determination unit 413A outputs the vibration detection information to the second HDC write inhibit determination unit 413B of the R / W channel 40B via the transmission path WR1 and the HDC60B, and invalidates (negates or deasserts) the write enable via the second HDC write inhibit determination unit 413B, thereby inhibiting (or stopping) writing (or writing action) of the head HD1.

[0167] For example, when a write inhibit signal is received from HDC60A to inhibit (or stop) writing (or writing action) of head HD1, the second HDC write inhibit determination unit 413A outputs the signal to inhibit writing (or writing action) of head HD1 to HDC60B, and outputs the write inhibit signal to the second HDC write inhibit determination unit 413B of the R / W channel 40B via the transmission path WR1 and HDC60B, and the write enable is invalidated (negate or deassert) via the second HDC write inhibit determination unit 413B, thereby inhibiting (or stopping) writing (or writing action) of head HD1. In other words, when receiving a write inhibit signal including a signal for inhibiting (or stopping) writing (or writing action) of the head HD1 from HDC60A and vibration detection information indicating that the head HD1 is subjected to vibration, the second HDC write inhibit determination unit 413A outputs a signal for inhibiting writing (or writing action) of the head HD1 to HDC60B, outputs the vibration detection information to the second HDC write inhibit determination unit 413B of the R / W channel 40B via the transmission path WR1 and HDC60B, and invalidates (negates or deasserts) the write enable via the second HDC write inhibit determination unit 413B, thereby inhibiting (or stopping) writing (or writing action) of the head HD1.

[0168] The MPU 50A controls the actuator AC0 via the driver IC 20A, performing servo control to position the head HD0. The MPU 50A controls writing data to the disk DK0 and selects the storage destination for the written data. Furthermore, the MPU 50A controls reading data from the disk DK0 and processes the read data. The MPU 50A is connected to various components of the magnetic disk drive 1. For example, the MPU 50A is electrically connected to the driver IC 20A, the R / W channel 40A, and the HDC 60A.

[0169] The HDC 60A controls read / write processing based on instructions from the MPU 50A, controlling data transfer between the host computer 700 and the R / W channel 40A. The HDC 60A is electrically connected to, for example, the R / W channel 40A, the MPU 50A, the volatile memory 70, the buffer memory 80, and the nonvolatile memory 90. The HDC 60A is connected to the R / W channel 40B via the transmission path WR0. Alternatively, the HDC 60A may not be connected to the R / W channel 40B via the transmission path WR0.

[0170] The HDC60A includes a servo control unit 610A and a write operation determination unit 620A. The HDC60A executes the processing of each of the aforementioned units, such as the servo control unit 610A and the write operation determination unit 620A, in firmware. Furthermore, the HDC60A may include each of the aforementioned units as circuits. Furthermore, a portion of the HDC60A configuration may be provided within the MPU50A. For example, the servo control unit 610A and the write operation determination unit 620A may also be provided within the MPU50A. The HDC60A prohibits (or stops) the write operation of the head HD0. For example, upon receiving a write prohibition signal, the HDC60A prohibits (or stops) the write operation of the head HD0.

[0171] The servo control unit 610A controls the position of the head HD0. In other words, the servo control unit 610A controls access to a predetermined area of ​​the disk DK0 by the head HD0. The servo control unit 610A includes a tracking control unit 611A and a seek control unit 612A.

[0172] The tracking control unit 611A controls the head HD0 to track a predetermined track of the disk DK0. The tracking control unit 611A includes a DPES demodulator 6111A. Alternatively, the tracking control unit 611A may include an SPES demodulator.

[0173] The DPES demodulation unit 6111A reads the data sector DS of the disk DK0 and demodulates the DPES.

[0174] The seek control unit 612A controls the head HD0 to seek from a predetermined track to a target track on the disk DK0.

[0175] The write operation determination unit 620A is connected to the R / W channel 40B via the wiring WR0. Alternatively, the write operation determination unit 620A may not be connected to the R / W channel 40B via the wiring WR0. The write operation determination unit 620A includes a position write operation determination unit 621A and a speed write operation determination unit 622A. The position write operation determination unit 621A determines the write operation of the head HD0 based on the position of the head HD0. The speed write operation determination unit 622A determines the write operation of the head HD0 based on the speed of the head HD0.

[0176] The write operation determination unit 620A determines whether or not writing (or writing operation) by the head HD0 corresponding to the HDC 60A is prohibited (or stopped).

[0177] When receiving a write prohibition determination signal (or write prohibition determination information) for writing (or writing action) of the head HD0 corresponding to HDC60A, the write action determination unit 620A determines whether to prohibit (or stop) writing (or writing action) of the head HD0 based on the SPES demodulated by reading from the servo sector SS of the disk DK0 by the head HD0 or the DPES demodulated by reading from the data sector DS.

[0178] Upon receiving a write inhibit determination signal (or write inhibit determination information) for writing (or writing operation) of the head HD0 corresponding to the HDC 60A, the write operation determination unit 620A determines whether the SPES or DPES corresponding to the head HD0 exceeds a threshold value.

[0179] When it is determined that the SPES or DPES corresponding to head HD0 exceeds the threshold, the write operation determination unit 620A determines to prohibit (or stop) writing (or writing operation) of head HD0 and outputs a write prohibition signal to the R / W channel 40A corresponding to HDC60A.

[0180] When receiving a signal from the second HDC write inhibit determination unit 413A to inhibit writing (or a write operation) by the head HD1 corresponding to the HDC 60B, the write operation determination unit 620A may output a write inhibit signal to the R / W channel 40B. When receiving a signal from the second HDC write inhibit determination unit 413A to inhibit writing (or a write operation) by the head HD1 corresponding to the HDC 60B, the write operation determination unit 620A may output a write inhibit signal to the R / W channel 40B via the transmission path WR0.

[0181] In addition, when receiving a signal from the second HDC write prohibition determination unit 413A to prohibit writing (or writing action) of the head HD1 corresponding to HDC60B, the write action determination unit 620A may not output a write prohibition signal to the R / W channel 40B according to the status of the system controller 130B, the head HD1, etc.

[0182] For example, when determining that the SPES or DPES corresponding to the head HD0 exceeds the threshold, the write operation determination unit 620A may output a write inhibit signal to the R / W channel 40B.

[0183] For example, if the SPES or DPES corresponding to head HD0 is determined to be below the threshold, the write operation determination unit 620A prohibits (or stops) writing (or writing operation) by head HD0 without passing through HDC 60A. In other words, if the SPES or DPES corresponding to head HD0 is determined to be below the threshold, the write operation determination unit 620A continues (or continues) writing (or writing operation) by head HD0.

[0184] System controller 130B includes R / W channel 40B, MPU 50B, and HDC 60B. System controller 130B is electrically connected to driver IC 20B, head amplifier IC 30B, write disable detector 180, controller communication unit 190, and host system 700. System controller 130B is electrically connected to system controller 130A via transmission paths WR0 and WR1. System controller 130B may also include SPM control unit 210B, VCM control unit 220B, and MA control unit 230B. System controller 130B may also include driver IC 20B and head amplifier IC 30B.

[0185] The R / W channel 40B performs signal processing for read data transferred from the disk DK1 to the host computer 700 and for write data transferred from the host computer 700, in accordance with instructions from the MPU 50B. The R / W channel 40B is electrically connected to, for example, the head amplifier IC 30B, the MPU 50B, the HDC 60B, and the write inhibit detector 180. The R / W channel 40B is connected to the write operation determination unit 620A (HDC 60A) via the transmission path WR0. Alternatively, the R / W channel 40B may not be connected to the write operation determination unit 620A (HDC 60A) via the transmission path WR0. The R / W channel 40B includes a write inhibit unit 410B.

[0186] The write inhibit unit 410B inhibits (or stops) writing (or writing operations) by the heads HD0 and HD1 via the HDCs 60A and 60B. The write inhibit unit 410B is connected to the write operation determination unit 620A (HDC 60A) via the transmission path WR0. Alternatively, the write inhibit unit 410B may not be connected to the write operation determination unit 620A (HDC 60A) via the transmission path WR0. The write inhibit unit 410B includes a vibration sensor write inhibit determination unit 411B, a first HDC write inhibit determination unit 412B, and a second HDC write inhibit determination unit 413B.

[0187] When vibration or impact is detected by the vibration sensor 170, the vibration sensor write prohibition determination unit 411B determines whether to prohibit (or stop) writing (or writing action) performed by the head HD1 of the actuator AC1 or not.

[0188] For example, when a write inhibit determination execution signal is received, the vibration sensor write inhibit determination unit 411B determines whether to prohibit (or stop) writing (or writing action) performed by at least one head HD corresponding to the actuator AC1 or not to prohibit (or stop) writing (or writing action).

[0189] For example, upon receiving a write inhibit determination execution signal, the vibration sensor write inhibit determination unit 411B determines whether the vibration or shock is greater than a predetermined value based on the write inhibit determination execution signal. For example, if the vibration or shock is determined to be greater than the predetermined value, the vibration sensor write inhibit determination unit 411B determines to inhibit (or stop) writing (or a write operation) to the at least one head HD1 of the actuator AC1. For example, if the vibration or shock is determined to be greater than the predetermined value, the vibration sensor write inhibit determination unit 411B outputs a write inhibit determination signal indicating that writing (or a write operation) to the at least one head HD1 of the actuator AC1 is prohibited (or stopped). For example, if the vibration or shock is determined to be below the predetermined value, the vibration sensor write inhibit determination unit 411B does not determine to inhibit (or stop) writing (or a write operation) to the at least one head HD1 of the actuator AC1.

[0190] The first HDC write inhibit determination unit 412B inhibits (or stops) writing (or the writing operation) to the head HD0 corresponding to the HDC 60A. For example, upon receiving a write inhibit signal from the HDC 60B to inhibit (or stop) writing (or the writing operation) to the head HD0, the first HDC write inhibit determination unit 412B outputs the write inhibit signal to the first HDC write inhibit determination unit 412A of the R / W channel 40A via the HDC 60B and the transmission path WR1. The write strobe is negated (negate or deassert) via the first HDC write inhibit determination unit 412A, thereby inhibiting (or stopping) writing (or the writing operation) to the head HD0. In other words, when receiving a write inhibit signal including a signal for inhibiting (or stopping) writing (or writing action) of the head HD0 from the HDC60B and vibration detection information indicating that the head HD0 is subjected to vibration, the first HDC write inhibit determination unit 412B outputs the vibration detection information to the first HDC write inhibit determination unit 412A of the R / W channel 40A via the HDC60B and the transmission path WR1, and invalidates (negates or deasserts) the write enable via the first HDC write inhibit determination unit 412A, thereby inhibiting (or stopping) writing (or writing action) of the head HD0.

[0191] For example, when a write inhibit signal is received from HDC60B to inhibit (or stop) writing (or writing action) of head HD0, the first HDC write inhibit determination unit 412B outputs a signal to inhibit writing (or writing action) of head HD0 to HDC60B, and outputs the write inhibit signal to the first HDC write inhibit determination unit 412A of the R / W channel 40A via HDC60B and the transmission path WR1, and the write enable is invalidated (negate or deassert) via the first HDC write inhibit determination unit 412A, thereby inhibiting (or stopping) writing (or writing action) of head HD0. In other words, when receiving a write inhibit signal including a signal for inhibiting (or stopping) writing (or writing action) of the head HD0 from HDC60B and vibration detection information indicating that the head HD0 is subjected to vibration, the first HDC write inhibit determination unit 412B outputs a signal for inhibiting writing (or writing action) of the head HD0 to HDC60B, outputs the vibration detection information to the first HDC write inhibit determination unit 412A of the R / W channel 40A via HDC60B and the transmission path WR1, and invalidates (negates or deasserts) the write enable via the first HDC write inhibit determination unit 412A, thereby inhibiting (or stopping) writing (or writing action) of the head HD0.

[0192] For example, when a write inhibit signal is received from HDC60B to inhibit (or stop) writing (or writing action) of head HD0, the first HDC write inhibit determination unit 412B outputs the write inhibit signal to the first HDC write inhibit determination unit 412A of the R / W channel 40A via the transmission path WR0 and HDC60A, and the write enable is invalidated (negate or deassert) via the first HDC write inhibit determination unit 412A, thereby inhibiting (or stopping) writing (or writing action) of head HD0. In other words, when receiving a write inhibit signal including a signal for inhibiting (or stopping) writing (or writing action) of the head HD0 from HDC60B and vibration detection information indicating that the head HD0 is subjected to vibration, the first HDC write inhibit determination unit 412B outputs the vibration detection information to the first HDC write inhibit determination unit 412A of the R / W channel 40A via the transmission path WR0 and HDC60A, and invalidates (negates or deasserts) the write enable via the first HDC write inhibit determination unit 412A, thereby inhibiting (or stopping) writing (or writing action) of the head HD0.

[0193] For example, when a write inhibit signal is received from HDC60B to inhibit (or stop) writing (or writing action) of head HD0, the first HDC write inhibit determination unit 412B outputs the signal to inhibit writing (or writing action) of head HD0 to HDC60A, and outputs the write inhibit signal to the first HDC write inhibit determination unit 412A of the R / W channel 40A via the transmission path WR0 and HDC60A, and the write enable is invalidated (negate or deassert) via the first HDC write inhibit determination unit 412A, thereby inhibiting (or stopping) writing (or writing action) of head HD0. In other words, when receiving vibration detection information including a write inhibit signal for inhibiting (or stopping) writing (or writing action) of head HD0 from HDC60B, which indicates that head HD0 is subjected to vibration, the first HDC write inhibit determination unit 412B outputs a signal for inhibiting writing (or writing action) of head HD0 to HDC60A, outputs the vibration detection information to the first HDC write inhibit determination unit 412A of the R / W channel 40A via the transmission path WR0 and HDC60A, and invalidates (negates or deasserts) the write enable via the first HDC write inhibit determination unit 412A, thereby inhibiting (or stopping) writing (or writing action) of head HD0.

[0194] The second HDC write inhibit determination unit 413B inhibits (or stops) writing (or the writing operation) of the head HD1 corresponding to the HDC 60B. For example, upon receiving a write inhibit signal from the HDC 60B to inhibit (or stop) writing (or the writing operation) of the head HD1, the second HDC write inhibit determination unit 413B negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or the writing operation) of the head HD1. In other words, upon receiving a write inhibit signal from the HDC 60B to inhibit (or stop) writing (or the writing operation) of the head HD1 and vibration detection information indicating that the head HD1 is vibrating, the second HDC write inhibit determination unit 413B negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or the writing operation) of the head HD1.

[0195] For example, upon receiving a write inhibit signal for writing (or a write operation) to head HD0 corresponding to HDC 60A, the second HDC write inhibit determination unit 413B negates (negates or deasserts) the write strobe, thereby prohibiting (or stopping) writing (or a write operation) to head HD1. In other words, upon receiving vibration detection information including a write inhibit signal for writing (or a write operation) to head HD0 corresponding to HDC 60A and indicating that head HD0 is vibrating, the second HDC write inhibit determination unit 413B negates (negates or deasserts) the write strobe, thereby prohibiting (or stopping) writing (or a write operation) to head HD1.

[0196] The MPU 50B controls the actuator AC1 via the driver IC 20B, performing servo control to position the head HD1. The MPU 50B controls writing data to the disk DK1 and selects the storage destination for the written data. Furthermore, the MPU 50B controls reading data from the disk DK1 and processes the read data. The MPU 50B is connected to various components of the magnetic disk drive 1. For example, the MPU 50B is electrically connected to the driver IC 20B, the R / W channel 40B, and the HDC 60B.

[0197] HDC 60B controls read / write processing based on instructions from MPU 50B, controlling data transfer between host 700 and R / W channel 40B. HDC 60B is electrically connected to, for example, R / W channel 40B and MPU 50B. HDC 60B is connected to R / W channel 40A via transmission path WR1. Alternatively, HDC 60B may not be connected to R / W channel 40A via transmission path WR1.

[0198] The HDC 60B includes a servo control unit 610B and a write operation determination unit 620B. The HDC 60B executes the processing of each of the aforementioned units, such as the servo control unit 610B and the write operation determination unit 620B, in firmware. Alternatively, the HDC 60B may include each of the aforementioned units as circuits. Furthermore, a portion of the HDC 60B's components may be incorporated into the MPU 50B. For example, the servo control unit 610B and the write operation determination unit 620B may also be incorporated into the MPU 50B. The HDC 60B inhibits (or stops) the write operation of the head HD1. For example, upon receiving a write inhibit signal, the HDC 60B inhibits (or stops) the write operation of the head HD1.

[0199] The servo control unit 610B controls the position of the head HD1. In other words, the servo control unit 610B controls access to a predetermined area of ​​the disk DK1 by the head HD1. The servo control unit 610B includes a tracking control unit 611B and a seek control unit 612B.

[0200] The tracking control unit 611B controls the head HD1 to track a predetermined track of the disk DK1. The tracking control unit 611B includes a DPES demodulator 6111B. Alternatively, the tracking control unit 611B may include an SPES demodulator.

[0201] The DPES demodulation unit 6111B reads the data sector DS of the disk DK1 and demodulates the DPES.

[0202] The seek control unit 612B controls the head HD1 to seek from a predetermined track to a target track on the disk DK1.

[0203] The write operation determination unit 620B is connected to the R / W channel 40A via the wiring WR1. Alternatively, the write operation determination unit 620B may not be connected to the R / W channel 40A via the wiring WR1. The write operation determination unit 620B includes a position write operation determination unit 621B and a speed write operation determination unit 622B. The position write operation determination unit 621B determines the write operation of the head HD1 based on the position of the head HD1. The speed write operation determination unit 622B determines the write operation of the head HD1 based on the speed of the head HD1.

[0204] The write operation determination unit 620B determines whether or not to prohibit (or stop) writing (or the write operation) of the head HD1 corresponding to the HDC 60B.

[0205] When receiving a write prohibition determination signal (or write prohibition determination information) for writing (or writing action) of the head HD1 corresponding to HDC60B, the write action determination unit 620B determines whether to prohibit (or stop) writing (or writing action) of the head HD1 based on the SPES demodulated by reading from the servo sector SS of the disk DK1 or the DPES demodulated by reading from the data sector DS by the head HD1.

[0206] Upon receiving a write inhibit determination signal (or write inhibit determination information) for writing (or writing operation) of the head HD1 corresponding to the HDC 60B, the write operation determination unit 620B determines whether the SPES or DPES corresponding to the head HD1 exceeds a threshold value.

[0207] When determining that the SPES or DPES corresponding to head HD1 exceeds the threshold, the write operation determination unit 620B determines to prohibit (or stop) writing (or writing operation) of head HD1 and outputs a write prohibition signal to the R / W channel 40B corresponding to HDC60B.

[0208] When receiving a signal from the first HDC write inhibit determination unit 412B prohibiting writing (or a write operation) to the head HD0 corresponding to the HDC 60A, the write operation determination unit 620B may output a write inhibit signal to the R / W channel 40A. When receiving a signal from the first HDC write inhibit determination unit 412B prohibiting writing (or a write operation) to the head HD0 corresponding to the HDC 60A, the write operation determination unit 620B may output a write inhibit signal to the R / W channel 40A via the transmission path WR1.

[0209] In addition, when receiving a signal from the first HDC write prohibition determination unit 412B to prohibit writing (or writing action) of the head HD0 corresponding to HDC60A, the write action determination unit 620B may not output a write prohibition signal to the R / W channel 40A based on the status of the system controller 130A, the head HD0, etc.

[0210] For example, when determining that the SPES or DPES corresponding to the head HD1 exceeds the threshold, the write operation determination unit 620B may output a write inhibit signal to the R / W channel 40A.

[0211] For example, if the SPES or DPES corresponding to head HD1 is determined to be below the threshold, the write operation determination unit 620B prohibits (or stops) writing (or writing operation) by head HD1 without passing through HDC 60B. In other words, if the SPES or DPES corresponding to head HD1 is determined to be below the threshold, the write operation determination unit 620B continues (or continues) writing (or writing operation) by head HD1.

[0212] Reference Figure 6 、 Figure 7 and Figure 8 , the demodulation method of DPES is explained.

[0213] Figure 6 This is a schematic diagram showing an example of a method for demodulating DPES based on data preambles with different frequencies in adjacent tracks. Figure 6 In FIG, the servo sector SS, the data sector DS, the signal output (output) (amplitude), the phase (Phase) (θa, θb), the normalized signal output (Normalized output) (hereinafter, sometimes also referred to as the normalized signal output), the coefficient k and the DPES are shown. Figure 6 In the embodiment, a plurality of tracks TR are continuously arranged in the radial direction. Figure 6 The read head RH and the write head WH are shown in FIG. Figure 6 The radial width Wr1 of the read head RH (hereinafter sometimes referred to as the width) and the width Ww of the write head WH are shown in FIG. Figure 6 In the servo sector SS and data sector DS, the horizontal axis represents the circumferential direction (circumferential position or down track), and the vertical axis represents the radial direction (radial position or cross track). The servo sector SS corresponds to Figures 3 to 5 The servo sector SS is shown. Figure 6 The servo sector SS shows the sector / cylinder width Ws. In addition, the sector / cylinder width can also be different for each track. Figure 6 In the data sector DS corresponds to Figure 3 The data sector DS is shown. Figure 6 The width Wd of each data sector DS is shown in the data sector DS. The width Wd is equivalent to the track pitch of each track TR. Figure 6 In the data sector DS, the data preamble is tile-recorded at a track pitch Wd using, for example, a write head WH having a width greater than or equal to the width Wd. Figure 6 The data preamble is written with a low recording frequency, for example, an A-phase pattern (A-phase pattern) naT having a lower recording frequency than the B-phase pattern (B-phase pattern) nbT described later, and a high recording frequency, for example, a B-phase pattern nbT having a higher recording frequency than the A-phase pattern naT. Figure 6 In the embodiment, multiple data preambles of multiple tracks TR arranged continuously in the radial direction are alternately written into the A-phase pattern naT and the B-phase pattern nbT. Figure 6 In the data preamble of two adjacent tracks, different patterns, such as different recording frequencies, are written. Since the fundamental frequency (fundamental frequency) of the pattern nT (naT, nbT) or a component containing its higher harmonics is used as a signal, the fundamental frequency of each (fundamental wave) is preferably a frequency that does not overlap with the frequency of the other higher harmonic. Figure 6 In the signal output (Output) of the data sector DS, the horizontal axis represents the signal output and the vertical axis represents the radial position. Figure 6The signal output (Output) of the data sector DS read out shows the signal output (A phase signal output) Va corresponding to the A phase pattern and the signal output (B phase signal output) Vb corresponding to the B phase pattern. Figure 6 In the phase (θa, θb), the horizontal axis represents the phase [radian] and the vertical axis represents the radial position. Figure 6 The phase of shows the phase corresponding to the A-phase signal output (A-phase phase) (θa) and the phase corresponding to the B-phase signal output (B-phase phase) (θb). Figure 6 In the standardized signal output of , the horizontal axis represents the standardized signal output and the vertical axis represents the radius position. Figure 6 The standardized signal output of shows the standardized signal output corresponding to the A-phase signal output (A-phase standardized signal output) Va′, and the standardized signal output corresponding to the B-phase signal output (B-phase standardized signal output) Vb′. Figure 6 In the coefficient k, the horizontal axis represents the coefficient k and the vertical axis represents the radius position. Figure 6 In DPES, the horizontal axis represents DPES [Data track] and the vertical axis represents the radial position.

[0214] When the read head RH reads a data sector, the system controller 130 performs a DFT (Discrete Fourier Transformation) operation at the frequencies corresponding to the A-phase pattern naT and the B-phase pattern nbT, respectively, to calculate the signal output and phase (A-phase phase θa and B-phase phase θb). Generally speaking, in magnetic recording, as the recording frequency increases, the signal output decreases. Therefore, the system controller 130 uses the following equations (1) and (2) to correct (normalize) this effect.

[0215] Va′=Va×kva Formula (1)

[0216] Vb′=Vb×kvb Formula (2)

[0217] Here, kva is the coefficient of phase A (phase A coefficient), and kvb is the coefficient of phase B (phase B coefficient).

[0218] The system controller 130 calculates a coefficient k for calculating DPES based on the following equation (3).

[0219]

[0220] As shown in the following equation (4), the system controller 130 determines the sign of the coefficient k based on the A-phase phase θa and the B-phase phase θb, and calculates the DPES in units of tracks.

[0221]

[0222] The system controller 130 converts the unit of the head HD by multiplying the DPES, which is expressed in track units, by the track pitch Wd. The system controller 130 calculates the position of the head HD within a predetermined data sector DS by adding the DPES, which contains only position information based on the track pitch Wd, to the position calculated based on the SPES demodulated from the track (cylinder) and null burst of the immediately preceding servo sector. To account for the velocity of the head HD at the immediately preceding demodulated position of the predetermined data sector DS, the system controller 130 may also calculate the position of the head HD within the predetermined data sector by adding the head HD position calculated based on the SPES and the DPES to the head HD position calculated based on the distance the head HD has moved to the predetermined data sector. Alternatively, the system controller 130 may calculate the SIN (sine) component and COS (cosine) component of the fundamental frequency of the recording frequency of the data preamble of the predetermined data sector DS and calculate the position of the head HD within the predetermined data sector DS based on the calculated SIN and COS components.

[0223] Figure 7 This is a schematic diagram showing an example of a method for demodulating DPES based on data pulse trains with different frequencies in adjacent tracks. Figure 7 In the data sector DS corresponds to Figure 4 The data sector DS is shown. Figure 7 The data sector DS includes a data burst (Burst). Figure 7 The data pulse train is written in the A-phase pattern naT and the B-phase pattern nbT. Figure 7 In the embodiment, a plurality of data pulse trains of a plurality of tracks TR arranged continuously in the radial direction are alternately written into the A-phase pattern naT and the B-phase pattern nbT. Figure 7 In the embodiment, data pulse trains of two adjacent tracks are written with different patterns, such as different recording frequencies.

[0224] and Figure 6 Similarly to the method of demodulating the DPES based on the data preamble shown, the system controller 130 demodulates the DPES based on the data pulse train and calculates the position of the head HD based on the demodulated DPES. Alternatively, the system controller 130 may calculate the SIN component and COS component of the fundamental frequency of the recording frequency of the data pulse train of the predetermined data sector DS and calculate the position of the head HD within the predetermined data sector DS based on the calculated SIN and COS components.

[0225] Figure 8 This is a schematic diagram showing an example of a method for demodulating DPES based on a data Null pulse train. Figure 8The servo sector SS, data sector DS, signal output (VN, VQ), phase (θV, θQ), coefficient k and DPES are shown in FIG. Figure 8 The width Wr2 of the read head RH is shown in FIG. Figure 8 In the data sector DS corresponds to Figure 4 The data sector DS is shown. Figure 8 In the data sector DS, the data Null burst is tile-recorded at the track pitch Wd using, for example, a write head WH having a width that is twice or more of the width Wd. Figure 8 The data sector DS includes a data Null burst. Figure 8 The data Null pulse train is written at a certain recording frequency in a pattern having a width of two tracks in the radial direction. Figure 8 The data Null pulse train has an N-phase data Null pulse train (N-phase data pulse train or data N pulse train) and a Q-phase data Null pulse train (Q-phase data pulse train or data Q pulse train) with phases shifted by 90° with 4 tracks as one cycle. Figure 8 In the signal output of the data Null pulse train (hereinafter sometimes referred to as Null pulse train signal output), the horizontal axis represents the Null pulse train signal output and the vertical axis represents the radius position. The Null pulse train signal output represents the signal output (N phase signal output) VN corresponding to the data N pulse train and the signal output (Q phase signal output) VQ corresponding to the data Q pulse train. Figure 8 In the phase, the horizontal axis represents the phase [radian] and the vertical axis represents the radial position. Figure 8 The phase of represents the phase corresponding to the N-phase signal output (N-phase phase) (θN) and the phase corresponding to the Q-phase signal output (Q-phase phase) (θQ). Figure 8 In the standardized signal output, the horizontal axis represents the standardized signal output and the vertical axis represents the radial position. Figure 8 The standardized signal output of shows the standardized signal output (N-phase standardized signal output) VN corresponding to the N-phase signal output and the standardized signal output (Q-phase standardized signal output) VQ corresponding to the Q-phase signal output. Figure 8 In the coefficient k, the horizontal axis represents the coefficient k and the vertical axis represents the radius position. Figure 8 In DPES, the horizontal axis represents DPES [Data track] and the vertical axis represents the radial position.

[0226] When the read head RH reads a data sector, the system controller 130 performs a DFT operation at a frequency corresponding to the data sector pattern to calculate signal outputs VN and VQ and phases θN and θQ. The system controller 130 calculates the coefficient k using the following equation (5).

[0227]

[0228] As shown in the following equation (6), the system controller 130 determines the sign of the coefficient k based on the N-phase phase θN and the Q-phase phase θQ, and calculates the DPES in units of tracks.

[0229]

[0230] The system controller 130 converts the unit of the head HD by multiplying the DPES, which is expressed in track units, by the track pitch Wd. The system controller 130 calculates the position of the head HD within a predetermined data sector DS by adding the DPES, which only includes position information based on the track pitch Wd, to the position calculated based on the SPES demodulated from the track (cylinder) and null burst of the immediately preceding servo sector, for example. Furthermore, to account for the speed of the head HD at the demodulated position immediately preceding the predetermined data sector DS, the system controller 130 may also calculate the position of the head HD within the predetermined data sector by adding the head HD position calculated based on the SPES to the DPES and adding the head HD's travel distance to the predetermined data sector.

[0231] Figure 9 This is a diagram showing an example of the timing of demodulating SPES and DPES. Figure 9 , the horizontal axis represents time. Figure 9 The time on the horizontal axis passes as it progresses toward the front end side of the arrow. Figure 9 In the figure, the timings for demodulating SPES (hereinafter, sometimes referred to as SPES demodulation timing, demodulation timing or timing) m, m+1 and m+2 are represented. Figure 9 In the time on the horizontal axis of , the SPES demodulation timings m, m+1, and m+2 are arranged at intervals toward the front end of the time arrow in the order in which they are described. Figure 9 In the figure, the timings for demodulating DPES (hereinafter, sometimes also referred to as DPES demodulation timing, demodulation timing or timing) n, n+1, n+2 and n+3 are represented. Figure 9In the time on the horizontal axis, DPES demodulation timings n, n+1, n+2, and n+3 are arranged at intervals toward the front end of the time arrow in the order of description. DPES demodulation timings n and n+1 are arranged between SPES demodulation timings m and m+1. DPES demodulation timing n is equivalent to the timing after SPES demodulation timing m, DPES demodulation timing n+1 is equivalent to the timing after DPES demodulation timing n, and SPES demodulation timing m+1 is equivalent to the timing after SPES demodulation timing n+1. DPES demodulation timings n+2 and n+3 are arranged between SPES demodulation timings m+1 and m+2. DPES demodulation timing n+2 is equivalent to the timing after SPES demodulation timing m+1, DPES demodulation timing n+3 is equivalent to the timing after DPES demodulation timing n+2, and SPES demodulation timing m+2 is equivalent to the timing after DPES demodulation timing n+3.

[0232] like Figure 9 As shown, the system controller 130 can obtain the radial position information (DPES) attached to the data sector DS at a shorter time interval than the time interval for obtaining the radial position information (SPES) attached to the servo sector SS. The system controller 130 obtains the SPES at SPES demodulation timings m, m+1, and m+2. The system controller 130 obtains the DPES at DPES demodulation timings n, n+1, n+2, and n+3. The system controller 130 can use the DPES for servo positioning control and for determining whether to inhibit (or stop) writing to the data sector DS.

[0233] Figure 10 Schematic diagram showing an example of a method for determining prohibition of a write operation according to this embodiment. Figure 10 In FIG, the horizontal axis represents time, and the vertical axis represents position error (and radial position). Figure 10 The time on the horizontal axis passes as it progresses toward the front end side of the arrow. Figure 10 The time on the horizontal axis of represents time t0 and t1. Time t1 corresponds to the time after time t0. Time t0 corresponds to the current sampling radial position (hereinafter sometimes referred to as current position or current position error) P0 of the head HD. Figure 10 As for the time on the vertical axis, the positive value increases toward the front end side of the positive arrow, and the negative value decreases toward the front end side of the negative arrow. Figure 10 The position error on the vertical axis represents the thresholds +th and -th. The absolute values ​​of the thresholds +th and -th are the same. Figure 10 The vertical axis shows the current position (current position error) P0 of the head HD.

[0234] exist Figure 10In the example shown, the system controller 130 determines whether the current position (current position error) P0 of the head HD exceeds the threshold values ​​+th and -th. The system controller 130 determines that the current position (current position error) P0 of the head HD exceeds the threshold value +th. If the system controller 130 determines that the current position (current position error) of the head HD exceeds the threshold value +th, it prohibits (or stops) the write operation.

[0235] Figure 11 Schematic diagram showing an example of a method for determining prohibition of a write operation according to this embodiment. Figure 11 In FIG, the horizontal axis represents time, and the vertical axis represents position error (and radial position). Figure 11 The time on the horizontal axis passes as it progresses toward the front end side of the arrow. Figure 11 The time on the horizontal axis of represents the time t0 and t1. Figure 11 In the example, time t1 corresponds to the estimated radial position P1 of the next sampling of the head HD (hereinafter sometimes referred to as the next estimated position or the next position error). Figure 11 The time on the horizontal axis represents the time interval Δtsample between time t0 and time t1. Figure 11 The position error on the vertical axis represents the threshold values ​​+th and -th. Figure 11 The vertical axis of represents the next estimated position (next position error) P1 of the head HD.

[0236] exist Figure 11 In the example shown, the system controller 130 calculates the next estimated position (next position error) P1 of the head HD. The system controller 130 calculates the next estimated position (next position error) P1 based on the current position (current position error) P0 of the head HD, the velocity v0 of the head HD, and the time interval Δtsample using the following equation (7).

[0237] P1=P0+v0×Δtsample Formula (7)

[0238] Figure 12 It is a schematic diagram showing an example of a method for determining whether or not the write operation of the plurality of heads HD of the plurality of actuators AC is prohibited. Figure 12Indicated in the figure are the timing of demodulating SPES by reading the data sector DS by the effective head HD0 of actuator AC0 (hereinafter sometimes referred to as the SPES demodulation timing of head HD0), the timing of demodulating DPES by reading the data sector DS by the effective head HD0 of actuator AC0 (hereinafter sometimes referred to as the DPES demodulation timing of head HD0), the timing of demodulating SPES by reading the data sector DS by the effective head HD1 of actuator AC1 (hereinafter sometimes referred to as the SPES demodulation timing of head HD1), and the timing of demodulating DPES by reading the data sector DS by the effective head HD1 of actuator AC1 (hereinafter sometimes referred to as the DPES demodulation timing of head HD1). Figure 12 , the horizontal axis represents time. Figure 12 The time on the horizontal axis passes as it progresses toward the front end side of the arrow.

[0239] Figure 12 The SPES demodulation timings h, h+1, and h+2 of the head HD0 are shown in FIG. Figure 12 In the time on the horizontal axis, the SPES demodulation timings h, h+1, and h+2 of the head HD0 are arranged at intervals toward the front end of the time arrow in the order in which they are described. Figure 12 DPES demodulation timings i, i+1, i+2, i+3 and i+4 of the head HD0 are shown in FIG. Figure 12 In the time on the horizontal axis, the DPES demodulation timings i, i+1, i+2, i+3, and i+4 of head HD0 are arranged in the order of description, spaced apart toward the front end of the time arrow. The DPES demodulation timings i and i+1 of head HD0 are arranged between the SPES demodulation timings h and h+1 of head HD0. The DPES demodulation timing i of head HD0 corresponds to the timing after the SPES demodulation timing h of head HD0, the DPES demodulation timing i+1 of head HD0 corresponds to the timing after the DPES demodulation timing i of head HD0, and the SPES demodulation timing h+1 of head HD0 corresponds to the timing after the DPES demodulation timing i+1 of head HD0. The DPES demodulation timings i+2 and i+3 of head HD0 are arranged between the SPES demodulation timings h+1 and h+2 of head HD0. The DPES demodulation timing i+2 of head HD0 is equivalent to the timing after the SPES demodulation timing h+1 of head HD0. The DPES demodulation timing i+3 of head HD0 is equivalent to the timing after the DPES demodulation timing i+2 of head HD0. The SPES demodulation timing h+2 of head HD0 is equivalent to the timing after the DPES demodulation timing i+3 of head HD0. The DPES demodulation timing i+4 of head HD0 is equivalent to the timing after the SPES demodulation timing h+2 of head HD0.

[0240] Figure 12 The SPES demodulation timings j, j+1, and j+2 of the header HD1 are shown in FIG. Figure 12In the time on the horizontal axis of , the SPES demodulation timings j, j+1, and j+2 of the head HD1 are arranged at intervals toward the front end of the time arrow in the order in which they are described. Figure 12 DPES demodulation timings k, k+1, k+2, and k+3 of the head HD1 are shown in FIG. Figure 12 In the time on the horizontal axis, the DPES demodulation timings k, k+1, k+2, and k+3 of head HD1 are arranged in the order of description, spaced apart toward the front end of the time arrow. The DPES demodulation timings k and k+1 of head HD1 are arranged between the SPES demodulation timings j and j+1 of head HD1. The DPES demodulation timing k of head HD1 corresponds to the timing after the SPES demodulation timing j of head HD1, the DPES demodulation timing k+1 of head HD1 corresponds to the timing after the DPES demodulation timing k of head HD1, and the SPES demodulation timing j+1 of head HD1 corresponds to the timing after the DPES demodulation timing k+1 of head HD1. The DPES demodulation timings k+2 and k+3 of head HD1 are arranged between the SPES demodulation timings j+1 and j+2 of head HD1. The DPES demodulation timing k+2 of head HD1 is equivalent to the timing after the SPES demodulation timing j+1 of head HD1, the DPES demodulation timing k+3 of head HD1 is equivalent to the timing after the DPES demodulation timing k+2 of head HD1, and the SPES demodulation timing j+2 of head HD1 is equivalent to the timing after the DPES demodulation timing k+3 of head HD0.

[0241] exist Figure 12 , the DPES demodulation timing i of head HD0 is configured between the DPES demodulation timing k-1 of head HD1 and the SPES demodulation timing j of head HD1. The DPES demodulation timing i+1 of head HD0 is configured between the DPES demodulation timing k and k+1 of head HD1. The SPES demodulation timing h+1 of head HD0 and the DPES demodulation timing i+2 of head HD0 are configured between the DPES demodulation timing k+1 of head HD1 and the SPES demodulation timing j+1 of head HD1. The DPES demodulation timing i+3 of head HD0 is configured between the DPES demodulation timing k+2 and k+3 of head HD1. The SPES demodulation timing h+2 of head HD0 and the DPES demodulation timing i+4 of head HD0 are configured between the DPES demodulation timing k+3 of head HD1 and the SPES demodulation timing j+2 of head HD1.

[0242] exist Figure 12, the DPES demodulation timings i, i+1, i+2, i+3, and i+4 of head HD0 are different from the DPES demodulation timings k-1, k, k+1, k+2, and k+3 of head HD1. In other words, the DPES demodulation timings i, i+1, i+2, i+3, and i+4 of head HD0 are set to be offset relative to the DPES demodulation timings k-1, k, k+1, k+2, and k+3 of head HD1. In addition, the SPES demodulation timings h, h+1, and h+2 of head HD0 are different from the SPES demodulation timings j, j+1, and j+2 of head HD1. In other words, the SPES demodulation timings h, h+1, and h+2 of head HD0 are set to be offset relative to the DPES demodulation timings j, j+1, and j+2 of head HD1. That is, the data sectors DS (data preamble, data burst, or data null burst) of disk DK0 are arranged to be offset in the circumferential direction relative to the data sectors DS of disk DK1. Furthermore, the servo sectors SS of disk DK0 are arranged to be offset in the circumferential direction relative to the servo sectors SS of disk DK1. Furthermore, the servo sectors SS and data sectors DS may also be arranged to be offset in the circumferential direction on the upper surface FS0 and lower surface RS0 of disk DK0. The servo sectors SS and data sectors DS may also be arranged to be offset in the circumferential direction on the upper surface FS1 and lower surface RS1 of disk DK1. Figure 12 denoted in FIG. 5 , a time interval Δtk between the DPES demodulation timing i+1 of the head HD0 and the DPES demodulation timing k+1 of the head HD1 .

[0243] The system controller 130 performs self-servo writing on the servo sectors SS of disks DK0 and DK1 so that the data sector DS (data preamble, data pulse string, or data Null pulse string) of disk DK0 and the data sector DS (data preamble, data pulse string, or data Null pulse string) of disk DK1 are offset in the circumferential direction, and the servo sector SS of disk DK0 and the servo sector SS of disk DK1 are configured to be offset in the circumferential direction. In addition, the system controller 130 can also perform self-servo writing on the servo sectors SS of the upper surface FS0 and the lower surface RS0 of the disk DK0, so that the data sector DS (data preamble code, data pulse string or data Null pulse string) of the upper surface FS0 of the disk DK0 and the data sector DS (data preamble code, data pulse string or data Null pulse string) of the lower surface RS0 of the disk DK0 are offset in the circumferential direction, and the servo sector SS of the upper surface FS0 of the disk DK0 and the servo sector SS of the lower surface RS0 of the disk DK0 are configured to be offset in the circumferential direction. Alternatively, the system controller 130 may perform self-servo writing on the servo sectors SS on the upper surface FS1 and lower surface RS1 of the disk DK1, so that the data sectors DS (data preamble, data burst, or data null burst) on the upper surface FS1 of the disk DK1 and the data sectors DS (data preamble, data burst, or data null burst) on the lower surface RS1 of the disk DK1 are circumferentially offset, and the servo sectors SS on the upper surface FS1 of the disk DK1 and the servo sectors SS on the lower surface RS1 of the disk DK1 are circumferentially offset. In other words, the system controller 130 may set different data sector formats on each surface of the disk DK.

[0244] exist Figure 12 In the example shown, the system controller 130A performs self-servo writing on the servo sector SS to enable demodulation of the DPES at timings i, i+1, i+2, i+3, and i+4 and demodulation of the SPES at timings h, h+1, and h+2.

[0245] exist Figure 12 In the example shown, the system controller 130B performs self-servo writing on the servo sector SS to enable demodulation of the DPES at timings k-1, k, k+1, k+2, and k+3 and demodulation of the SPES at timings j, j+1, and j+2.

[0246] When the system controller 130 determines that the write operation is prohibited in the effective head HD of a predetermined actuator AC among multiple actuators AC, it outputs a write prohibition signal to prohibit the write operation of the effective head HD of an actuator AC different from the actuator AC to the HDC60 corresponding to the different actuator AC.

[0247] exist Figure 12In the example shown, system controller 130A causes head HD0, associated with actuator AC0, to demodulate DPES at DPES demodulation timing i+1. If system controller 130A determines that the DPES demodulated at DPES demodulation timing i+1 exceeds a threshold, it prohibits the write operation by head HD0 at DPES demodulation timing i+1. System controller 130A outputs a write-inhibit signal to system controller 130B via transmission path WR0. Upon receiving the write-inhibit signal, system controller 130B prohibits (stops) the write operation by head HD1, associated with actuator AC1, at DPES demodulation timing k+1. This prevents erroneous data writing to an area corresponding to time interval Δtk. For example, system controllers 130A and 130B preferably cause heads HD0 and HD1 to perform servo tracking on disk DK (DK0 and DK1), enabling DPES demodulation even when one of heads HD0 and HD1 is idle.

[0248] Figure 13 This is a block diagram showing an example of the positioning control system SYS of the head HD according to the present embodiment.

[0249] The magnetic disk drive 1 includes a positioning control system SYS for the head HD (hereinafter, sometimes simply referred to as the positioning control system). The positioning control system SYS includes a positioning control system CSYS0 for the head HD0 of the actuator AC0 (hereinafter, sometimes simply referred to as the positioning control system for the head HD0) and a positioning control system CSYS1 for the head HD1 of the actuator AC1 (hereinafter, sometimes simply referred to as the positioning control system for the head HD1).

[0250] The positioning control system CSYS0 for head HD0 includes a controller S01, a transfer characteristic (hereinafter sometimes referred to as a transfer characteristic) Fxact(A, B) S02 for mutual interference between actuators AC0 and AC1, a VCM S03, an MA S04, and calculation units CL01, CL02, and CL03. For example, the system controller 130A includes the controller S01. The transfer characteristic Fxact(A, B) S02 outputs a signal (hereinafter sometimes referred to as a first compensation signal) that compensates for the positional interference applied to head HD1. Fxact(A, B) S02 may also have parameters depending on the structure. VCM S03 corresponds to VCM 140. MA S04 corresponds to MA 160.

[0251] The positioning control system CSYS1 for head HD1 includes a controller S11, a transfer characteristic (hereinafter sometimes referred to as the transfer characteristic) Fxact(B, A) S12 for mutual interference between actuators AC0 and AC1, a VCM S13, an MA S14, and calculation units CL11, CL12, and CL13. For example, the system controller 130B includes the controller S11. The transfer characteristic Fxact(B, A) S12 outputs a signal (hereinafter sometimes referred to as the second compensation signal) that compensates for the positional interference applied to head HD0. The transfer characteristic Fxact(B, A) S12 may also have parameters depending on the structure. The VCM S13 corresponds to VCM141. The MA S14 corresponds to MA161.

[0252] The calculation unit CL01 receives the current position information (current position information) POS0 of the head HD0 and the target position of the head HD0 and outputs a position error PES0 of the head HD0 corresponding to the difference between the current position information POS0 of the head HD0 and the target position of the head HD0 to the controller S01.

[0253] The controller S01 receives the position error PES0 as input. The controller S01 outputs the position error PES0 to the transfer characteristic Fxact(A, B) S02, the VCM S03, and the computing unit CL02. The transfer characteristic Fxact(A, B) S02 receives the position error PES0 as input. The transfer characteristic Fxact(A, B) S02 converts the position error PES0 into a first compensation signal and outputs the converted first compensation signal to the computing unit CL12. The VCM S03 receives the position error PES0 as input. Based on the position error PES0, the VCM S03 outputs the amount of movement required to actuate the actuator AC0 (hereinafter sometimes referred to as the first amount of movement) to the computing unit CL03.

[0254] The position error PES0 and a second compensation signal, described later, are input to the calculation unit CL02. The calculation unit CL02 outputs the added value (hereinafter sometimes referred to as the first added value) obtained by adding the second compensation signal to the position error PES0 to the calculation unit CL04. The first added value is input to the MAS04. Based on the first added value, the MAS04 outputs the fine movement amount (hereinafter sometimes referred to as the first fine movement amount) for finely moving the head HD0 to the calculation unit CL03. The calculation unit CL03 receives the first movement amount and the first fine movement amount as inputs. The calculation unit CL03 outputs the current position information POS0, obtained by adding the first fine movement amount to the first movement amount, to the calculation unit CL01, thereby moving the head HD0 to the target position based on the current position information.

[0255] The calculation unit CL11 receives the current position information POS1 of the head HD1 and the target position of the head HD1 and outputs a position error PES1 of the head HD1 corresponding to the difference between the current position information POS1 of the head HD1 and the target position of the head HD1 to the controller S11.

[0256] The controller S11 receives the position error PES0 as input. The controller S11 outputs the position error PES1 to the transfer characteristic Fxact(B, A) S12, the VCM S13, and the computing unit CL12. The transfer characteristic Fxact(B, A) S12 receives the position error PES1 as input. The transfer characteristic Fxact(B, A) S12 converts the position error PES1 into a second compensation signal and outputs the converted second compensation signal to the computing unit CL02. The VCM S13 receives the position error PES1 as input. Based on the position error PES1, the VCM S13 outputs the amount of movement required to actuate the actuator AC1 (hereinafter sometimes referred to as the second amount of movement) to the computing unit CL13.

[0257] The position error PES1 and the first compensation signal are input to the arithmetic unit CL12. The arithmetic unit CL12 outputs the added value (hereinafter sometimes referred to as the second added value) obtained by adding the first compensation signal to the position error PES1 to the MA S14. The MA S14 receives the second added value as input. Based on the second added value, the MA S14 outputs the fine movement amount (hereinafter sometimes referred to as the second fine movement amount) for finely moving the head HD1 to the arithmetic unit CL13. The arithmetic unit CL13 receives the second movement amount and the second fine movement amount as input. The arithmetic unit CL13 outputs the current position information POS1 obtained by adding the second fine movement amount to the second movement amount to the arithmetic unit CL11, thereby moving the head HD1 to the target position based on the current position information.

[0258] Figure 14 This is a flowchart showing an example of a method for stopping a write operation according to this embodiment.

[0259] The system controller 130 reads a data sector using the head HD of the predetermined actuator AC (B1401). Based on predetermined information (or predetermined data) in the data sector, it demodulates and obtains the DPES (B1402). The predetermined information in the data sector may include, for example, a data preamble, a data burst, or a data null burst. The system controller 130 then determines whether the current position error corresponding to the head HD of the predetermined actuator AC is greater than a threshold for stopping the head HD (B1403).

[0260] If the system controller 130 determines that the current position error corresponding to the head HD of the predetermined actuator AC is below the threshold value (B1403: No), the system controller 130 determines whether the next position error of the head HD of the predetermined actuator AC is greater than the threshold value for stopping the head HD (B1404). If the next position error is determined to be below the threshold value (B1404: No), the system controller 130 proceeds to the process of B1401. If the next position error is determined to be greater than the threshold value (B1404: Yes), the system controller 130 proceeds to the process of B1405.

[0261] When it is determined that the current position error corresponding to the head HD of the predetermined actuator AC is greater than the threshold value (B1403: yes), the system controller 130 stops (prohibits) the writing action of the head HD of the predetermined actuator AC (B1405), and also stops (prohibits) the writing action of the head HD of other actuators AC different from the predetermined actuator AC (B1406), and ends the processing.

[0262] According to this embodiment, a magnetic disk drive 1 includes multiple disks DK, multiple heads HD corresponding to the multiple disks, multiple actuators AC corresponding to the multiple heads HD, and multiple system controllers 130 corresponding to the multiple actuators AC. The data sectors DS of the disks DK are arranged so as to be offset from one another in the circumferential direction. A predetermined system controller 130 among the multiple system controllers 130 uses the head HD of the predetermined actuator AC corresponding to the predetermined system controller 130 to read the servo sector SV of the disk DK corresponding to the predetermined head HD and demodulate the SPES. A predetermined system controller 130 uses the head HD of the predetermined actuator AC corresponding to the predetermined system controller 130 to read the data sector DS of the disk DK corresponding to the predetermined head HD and demodulate the DPES. The predetermined system controller 130 calculates the current position error of the predetermined head HD based on the SPES or DPES. If the current position error of the predetermined head HD exceeds a threshold for stopping (or inhibiting) the write operation of the predetermined head HD, the predetermined system controller 130 stops (or inhibits) the write operation of the predetermined head HD. When stopping (or disabling) write operations by a predetermined head HD, the predetermined system controller 130 can also stop (or disabling) write operations by heads HD of other actuators AC corresponding to other system controllers 130 other than the predetermined system controller 130. For example, the predetermined system controller 130 outputs a write disable signal to the other system controllers 130 via a transmission path (WR0 or WR1) such as a wiring, thereby stopping (or disabling) write operations by heads HD of the other actuators AC. By enabling the position error of the head HD to be determined based on the DPES (demodulated by reading data sectors) rather than based solely on the SPES (demodulated by reading servo sectors), the magnetic disk drive 1 can obtain the position error of the head HD in a shorter time interval. By stopping (or disabling) write operations based on the DPES (e.g., DPES), the magnetic disk drive 1 can stop (or disabling) write operations by the head HD in a shorter time period than if the write operations were stopped (or disabling) based solely on the SPES (e.g., DPES) when subjected to vibration and / or shock. The magnetic disk device 1 can make the threshold for stopping (or prohibiting) a write operation based on DPES or the like lower than the threshold for stopping (or prohibiting) a write operation based only on SPES. Furthermore, when stopping (prohibiting) writing (or the write operation) of the head HD of a predetermined actuator AC, the magnetic disk device 1 can also stop (prohibit) writing (or the write operation) of the heads HD of other actuators AC than that predetermined actuator AC. Therefore, the magnetic disk device 1 can achieve a high surface recording density for the data sector format. Consequently, the magnetic disk device 1 can improve formatting efficiency.

[0263] Next, magnetic disk devices according to other embodiments and modified examples will be described. In other embodiments and modified examples, the same reference numerals are given to the same parts as those in the aforementioned embodiment, and detailed description thereof will be omitted.

[0264] (Variation 1)

[0265] The configuration of the magnetic disk device 1 according to the first modification of the first embodiment is different from the configuration of the magnetic disk device 1 according to the first embodiment.

[0266] Figure 15 This is a schematic diagram showing an example of the configuration of the magnetic disk device 1 according to the first modification.

[0267] exist Figure 15 In the illustrated example, the communication unit 191 includes a write-inhibit information transmission unit 1911. The write-inhibit information transmission unit 1911 transmits a write-inhibit signal.

[0268] The write inhibit section 410 includes a vibration sensor write inhibit determination section 411 and a first HDC write inhibit determination section 412 or a second HDC write inhibit determination section 413 .

[0269] The write operation determination unit 620 further includes a PES write operation determination unit 623. The PES write operation determination unit 623 determines whether to prohibit (or stop) writing (or a write operation) by the predetermined head HD corresponding to the predetermined HDC 60 or the other HDC 60, based on the SPES or DPES demodulated by reading the servo sector SV or the data sector DS of the disk DK corresponding to the predetermined HDC 60 or the other HDC 60 by the predetermined head HD corresponding to the predetermined HDC 60 or the other HDC 60 via the predetermined HDC 60 or the other HDC 60.

[0270] For example, upon receiving a write-inhibit signal, the PES write operation determination unit 623 determines whether to inhibit (or stop) writing (or the write operation) to a predetermined head HD corresponding to a predetermined HDC 60 or another HDC 60. In other words, upon receiving vibration detection information, the PES write operation determination unit 623 determines whether to inhibit (or stop) writing (or the write operation) to a predetermined head HD corresponding to a predetermined HDC 60 or another HDC 60. If the PES write operation determination unit 623 determines that writing (or the write operation) to a predetermined head HD corresponding to a predetermined HDC 60 or another HDC 60 is inhibited (or stopped), the PES write operation determination unit 623 inhibits (or stops) writing (or the write operation) to a predetermined head HD corresponding to a predetermined HDC 60 or another HDC 60. If the PES write operation determination unit 623 determines that writing (or the write operation) to a predetermined head HD corresponding to a predetermined HDC 60 or another HDC 60 is inhibited (or stopped), the PES write operation determination unit 623 outputs a write-inhibit signal to a predetermined R / W channel 40 or another R / W channel 40 via the predetermined HDC 60 or another HDC 60 and the write-inhibit information transmission unit 1911. Furthermore, upon receiving a write inhibit signal, the PES write operation determination unit 623 may not inhibit (or stop) writing (or writing operation) of the predetermined head HD (write head WH) or other heads (write heads WH) based on the status of the predetermined system controller 130 or other system controllers 130, or the predetermined head HD corresponding to the predetermined HDC 60 or the predetermined head HD corresponding to another HDC 60. In other words, upon receiving a write inhibit signal, the PES write operation determination unit 623 may not output a write inhibit signal to the predetermined R / W channel 40 or other R / W channels based on the status of the predetermined system controller 130 or other system controllers 130, or the predetermined head HD corresponding to the predetermined HDC 60 or the predetermined head HD corresponding to another HDC 60.

[0271] For example, upon receiving a write inhibit signal, the PES write operation determination unit 623 inhibits (or stops) writing (or the writing operation) to the predetermined head HD corresponding to the predetermined HDC 60 or another HDC 60. In other words, upon receiving vibration detection information, the PES write operation determination unit 623 inhibits (or stops) writing (or the writing operation) to the predetermined head HD corresponding to the predetermined HDC 60 or another HDC 60. Upon receiving vibration detection information, the PES write operation determination unit 623 outputs the vibration detection information to the predetermined R / W channel 40 or another R / W channel 40 via the predetermined HDC 60 or another HDC 60 and the write inhibit information transmission unit 1911.

[0272] The write inhibit section 410A includes a vibration sensor write inhibit determination section 411A and a first HDC write inhibit determination section 412A.

[0273] The write operation determination unit 620A further includes a PES write operation determination unit 623A. The PES write operation determination unit 623A determines whether to prohibit (or stop) writing (or the write operation) by the head HD1 based on the SPES or DPES demodulated by reading the servo sector SV or the data sector DS of the disk DK1 corresponding to the HDC 60B via the HDC 60B by the head HD1 corresponding to the HDC 60B.

[0274] For example, upon receiving a write-inhibit signal that prohibits (or stops) writing (or a write operation) to head HD0, the PES write operation determination unit 623A outputs a write-inhibit signal that prohibits (or stops) writing (or a write operation) to head HD1 to the R / W channel 40B via the write-inhibit information transmission unit 1911 and the HDC 60B. In other words, upon receiving vibration detection information that includes a write-inhibit signal that prohibits (or stops) writing (or a write operation) to head HD0 and indicates that head HD0 is vibrating, the PES write operation determination unit 623A outputs vibration detection information that prohibits (or stops) writing (or a write operation) to head HD1 to the R / W channel 40B via the write-inhibit information transmission unit 1911 and the HDC 60B.

[0275] Furthermore, upon receiving a write-inhibit signal to inhibit (or stop) writing (or a write operation) to head HD0, the PES write operation determination unit 623A may not output the write-inhibit signal to inhibit (or stop) writing (or a write operation) to head HD1 to the R / W channel 40B, depending on the status of the system controller 130B or head HD1. In other words, upon receiving vibration detection information including a write-inhibit signal to inhibit (or stop) writing (or a write operation) to head HD0 and indicating that head HD0 is vibrating, the PES write operation determination unit 623A may not output vibration detection information to inhibit (or stop) writing (or a write operation) to head HD1 to the R / W channel 40B, depending on the status of the system controller 130B or head HD1.

[0276] The write inhibit section 410B includes a vibration sensor write inhibit determination section 411B and a second HDC write inhibit determination section 413B.

[0277] The write operation determination unit 620B further includes a PES write operation determination unit 623B. The PES write operation determination unit 623B determines whether to prohibit (or stop) writing (or the write operation) by the head HD0 based on the SPES or DPES demodulated by reading the servo sector SV or the data sector DS of the disk DK0 corresponding to the HDC 60A via the HDC 60A by the head HD0 corresponding to the HDC 60A.

[0278] For example, upon receiving a write-inhibit signal that prohibits (or stops) writing (or a write operation) to head HD1, the PES write operation determination unit 623B outputs the write-inhibit signal that prohibits (or stops) writing (or a write operation) to head HD0 to the R / W channel 40A via the write-inhibit information transmission unit 1911 and the HDC 60B. In other words, upon receiving vibration detection information that includes a write-inhibit signal that prohibits (or stops) writing (or a write operation) to head HD1 and indicates that head HD1 is vibrating, the PES write operation determination unit 623B outputs vibration detection information that prohibits (or stops) writing (or a write operation) to head HD0 to the R / W channel 40A via the write-inhibit information transmission unit 1911 and the HDC 60B.

[0279] Furthermore, upon receiving a write-inhibit signal to inhibit (or stop) writing (or a write operation) to head HD1, the PES write operation determination unit 623B may not output the write-inhibit signal to inhibit (or stop) writing (or a write operation) to head HD0 to the R / W channel 40A, depending on the status of the system controller 130A or head HD0. In other words, upon receiving vibration detection information including a write-inhibit signal to inhibit (or stop) writing (or a write operation) to head HD1 and indicating that head HD1 is vibrating, the PES write operation determination unit 623B may not output vibration detection information to inhibit (or stop) writing (or a write operation) to head HD0 to the R / W channel 40A, depending on the status of the system controller 130A or head HD0.

[0280] According to Modification 1, the magnetic disk drive 1 further includes a write-inhibit information transmission unit 1911. When the current position error of a predetermined head HD corresponding to a predetermined actuator exceeds a threshold for stopping (or inhibiting) the write operation of the predetermined head HD, the predetermined system controller 130 stops (or inhibits) the write operation by the predetermined head HD. When stopping (or inhibiting) the write operation by the predetermined head HD, the predetermined system controller 130 can also stop (or inhibit) the writing (or writing operation) of the heads HD of other actuators AC corresponding to other system controllers 130 other than the predetermined system controller 130 among the multiple system controllers 130. For example, the predetermined system controller 130 stops (or inhibits) the writing (or writing operation) of the heads HD of other actuators AC by outputting a write-inhibit signal (or vibration detection information) to the other system controllers 130 via the write-inhibit information transmission unit 1911. Therefore, the magnetic disk drive 1 can improve formatting efficiency.

[0281] (Second embodiment)

[0282] The configuration of the magnetic disk device 1 according to the second embodiment is different from the configurations of the magnetic disk devices 1 according to the first embodiment and the first modification.

[0283] Figure 16 It is a schematic diagram showing an example of the configuration of the magnetic disk device 1 according to the second embodiment.

[0284] exist Figure 16 In the example shown, disk DK includes disk DK2. Disk DK2 is mounted on spindle 12. Disk DK2 includes an upper surface FS2 and a lower surface RS2 opposite to upper surface FS2. Disk DK2 may include two or more disks.

[0285] The head HD includes a head HD2. The head HD2 includes a head HD20 facing the upper surface FS2 of the disk DK2, and a head HD21 facing the lower surface RS2 of the disk DK2. Furthermore, the head HD2 may include only one head or three or more heads. The head HD2 includes a write head WH2 for writing data to the disk DK2, and a read head RH2 for reading data written to the disk DK2. The write head WH2 includes a write head WH20 and a write head WH21. The read head RH2 includes a read head RH20 and a read head RH21.

[0286] The head HD20 includes a write head WH20 for writing data to the upper surface FS2 and a read head RH20 for reading data written to the upper surface FS2. The head HD21 includes a write head WH21 for writing data to the lower surface RS2 and a read head RH21 for reading data written to the lower surface RS2.

[0287] The actuator block BK includes an actuator block BK2 rotatably mounted on a bearing BR0 erected on the bottom wall HSB.

[0288] The arm AM includes an arm AM2. The arm AM2 includes an arm AM20 located on the upper surface FS2 side of the disk DK2 and an arm AM21 located on the lower surface RS2 side of the disk DK2. The arm AM2 may include only one arm or three or more arms, depending on the number of heads HD2. The arm AM2 is connected to the actuator block BK2.

[0289] The VCM 14 includes a VCM 142. The VCM 142 is connected to the actuator block BK2 on the side opposite to the arm AM2.

[0290] The suspension 15 includes a suspension 152. The suspension 152 is mounted on the arm AM2. The suspension 152 is equipped with a head HD2 at the top end on the side opposite to the end connected to the arm AM2. The suspension 152 includes a suspension 1520 mounted on the arm AM20 and a suspension 1521 mounted on the arm AM21. In addition, the suspension 152 may have only one suspension or three or more suspensions depending on the number of arms AM2. The suspension 1520 is equipped with a head HD20 at the top end on the side opposite to the end connected to the arm AM20. The suspension 1521 is equipped with a head HD21 at the top end on the side opposite to the end connected to the arm AM21.

[0291] The MA162 includes an MA162. The MA162 is mounted on the suspension 152. The MA162 finely controls the radial motion of the head HD2. For example, compared to the radial motion control of the head HD2 by the VCM 142, the MA162 provides more precise control of the radial motion of the head HD2. For example, the MA162 includes an MA1620 mounted on the suspension 1520 and an MA1621 mounted on the suspension 1521. Depending on the number of suspensions 152, the MA162 can include only one or three or more MAs.

[0292] MA1620 finely controls the radial motion of head HD20. For example, compared to the control of head HD20's radial motion by VCM142, MA1620 controls head HD20's radial motion more finely. MA1621 finely controls head HD21's radial motion. For example, compared to the control of head HD21's radial motion by VCM142, MA1621 controls head HD21's radial motion more finely. For example, MA1620 and MA1621 are driven independently of VCM142.

[0293] Actuator AC includes actuator AC2. Actuator AC2 is rotatably mounted on bearing BR1. Actuator AC2 consists of suspension 152, MA162, arm AM2, actuator block BK2, and VCM142. Actuator AC2 drives VCM142 around the rotation axis of bearing BR1 and precisely drives MA162, thereby positioning head HD2 mounted on suspension 152 at a predetermined position on disk DK2. If MA162 is not included, actuator AC2 drives VCM142 around bearing BR1, thereby positioning head HD2 mounted on suspension 152 at a predetermined position on disk DK2.

[0294] The driver IC 20 includes a driver IC 20C and a driver IC 20D. Driver ICs 20C and 20D are formed in separate configurations, such as separate circuits. Alternatively, driver ICs 20C and 20D may be formed in an integrated configuration, such as an integrated circuit. The SPM control unit 210 includes an SPM control unit 210C. The VCM control unit 220 includes a VCM control unit 220C. The MA control unit 230 includes MA control units 230C and 230D.

[0295] The driver IC 20C controls the driving of the SPM 13, VCM 142, and MA 1620 under the control of the system controller 130C (specifically, the MPU 50C or HDC 60C described later). The driver IC 20C is electrically connected to the SPM 13, driver IC 20D, VCM 142, and MA 1620. The driver IC 20C is connected to the SPM 13, driver IC 20D, VCM 142, and MA 1620, for example, via a predetermined interface.

[0296] The driver IC 20C includes an SPM control unit 210C, a VCM control unit 220C, and a microactuator (MA) control unit 230C. The SPM control unit 210C controls the rotation of the SPM 13. The VCM control unit 220C controls the drive of the VCM 142 by controlling the current (or voltage) supplied to the VCM 142. The MA control unit 230C controls the drive of the MA 1620 by controlling the current (or voltage) supplied to the MA 1620. Alternatively, a portion of the driver IC 20C components (e.g., the SPM control unit 210C, the VCM control unit 220C, and the MA control unit 230C) may be provided in the system controller 130C. If the actuator AC2 does not include the MA 1620, the MA control unit 230C may also be omitted.

[0297] The driver IC 20D controls the driving of the SPM 13, VCM 142, and MA 1621 under the control of the system controller 130D (specifically, the MPU 50D or HDC 60D described later). The driver IC 20D is electrically connected to the SPM 13, driver IC 20C, VCM 142, and MA 1621. The driver IC 20D is connected to the SPM 13, driver IC 20C, VCM 142, and MA 1621, for example, via a predetermined interface.

[0298] The driver IC 20D includes an MA control unit 230D. The SPM control unit 210D controls the rotation of the SPM 13. The VCM control unit 220D controls the drive of the VCM 142 by controlling the current (or voltage) supplied to the VCM 142. The MA control unit 230D controls the drive of the MA 1621 by controlling the current (or voltage) supplied to the MA 1621. Alternatively, a portion of the driver IC 20D (e.g., the MA control unit 230D) may be provided in the system controller 130D. If the actuator AC2 does not include the MA 1621, the MA control unit 230D may also be omitted.

[0299] The head amplifier IC 30 includes a head amplifier IC 30C and a head amplifier IC 30D. The head amplifier ICs 30C and 30D are formed in separate configurations, such as separate circuits. Alternatively, the head amplifier ICs 30C and 30D may be formed in an integrated configuration, such as an integrated circuit. The head selector 310 includes head selectors 310C and 310D. The read signal detector 320 includes read signal detectors 320C and 320D.

[0300] The head amplifier IC 30C amplifies the read signal received from the top surface FS2 of the disk DK2 and outputs it to the system controller 130C (specifically, the read / write (R / W) channel 40C described later). The head amplifier IC 30C is electrically connected to the head HD20. Furthermore, the head amplifier IC 30C outputs a write current to the head HD20 in accordance with the signal output from the R / W channel 40C.

[0301] The head amplifier IC 30C includes a head selector 310C and a read signal detector 320C. The head selector 310C selects the read head RH20 in the actuator AC2 to read data from the top surface FS2 of the disk DK2. The read signal detector 320C detects the signal (read signal) read by the read head RH20 from the top surface FS2 of the disk DK2. Alternatively, a portion of the components of the head amplifier IC 30C (e.g., the head selector 310C and the read signal detector 320C) may be provided in the system controller 130C.

[0302] The head amplifier IC 30D amplifies the read signal received from the lower surface RS2 of the disk DK2 and outputs it to the system controller 130D (specifically, the read / write (R / W) channel 40D described later). The head amplifier IC 30D is electrically connected to the head HD 21. Furthermore, the head amplifier IC 30D outputs a write current to the head HD 21 in accordance with the signal output from the R / W channel 40D.

[0303] The head amplifier IC 30D includes a read head selection unit 310D and a read signal detection unit 320D. The read head selection unit 310D selects the read head RH21 in the actuator AC2, which reads data from the lower surface RS2 of the disk DK2. The read signal detection unit 320D selects the read head RH21, which reads data from the lower surface RS2 of the disk DK2. The read signal detection unit 320D detects the signal (read signal) read by the read head RH21 from the lower surface RS2 of the disk DK2. Alternatively, a portion of the components of the head amplifier IC 30D (e.g., the read head selection unit 310D and the read signal detection unit 320D) may be provided in the system controller 130D.

[0304] The system controller 130 includes system controllers 130C and 130D. The system controllers 130C and 130D are formed in separate configurations, such as separate circuits. Alternatively, the system controllers 130C and 130D may be formed in an integrated configuration, such as an integrated circuit.

[0305] The R / W channel 40 includes R / W channels 40C and 40D. The vibration sensor write inhibit determination unit 411 includes vibration sensor write inhibit determination units 411C and 411D. The first HDC write inhibit determination unit 412 includes first HDC write inhibit determination units 412C and 412D. The second HDC write inhibit determination unit 413 includes second HDC write inhibit determination units 413C and 413D.

[0306] The MPU 50 includes MPUs 50C and 50D. The HDC 60 includes HDCs 60C and 60D. The servo control unit 610 includes servo control units 610C and 610D. The tracking control unit 611 includes tracking control units 611C and 611D. The DPES demodulation unit 6111 includes DPES demodulation units 6111C and 6111D. The seek control unit 612 includes seek control units 612C and 612D. The write action determination unit 620 includes write action determination units 620C and 620D. The position write action determination unit 621 includes position write action determination units 621C and 621D. The speed write action determination unit 622 includes speed write action determination units 622C and 622D.

[0307] The system controller 130C includes an R / W channel 40C, an MPU 50C, and an HDC 60C. The system controller 130C is electrically connected to the driver IC 20C, the head amplifier IC 30C, the volatile memory 70, the buffer memory 80, the nonvolatile memory 90, the write inhibit detector 180, the controller communication unit 190, and the host system 700. The system controller 130C is electrically connected to the system controller 130D via transmission paths WR0 and WR1. The system controller 130C may also include an SPM control unit 210C, a VCM control unit 220C, and an MA control unit 230C. The system controller 130C may also include the driver IC 20C and the head amplifier IC 30C.

[0308] The R / W channel 40C performs signal processing for read data transmitted from the top surface FS2 of the disk DK2 to the host 700, and for write data transmitted from the host 700, based on instructions from the MPU 50C. The R / W channel 40C is electrically connected to, for example, the head amplifier IC 30C, the MPU 50C, the HDC 60C, and the write inhibit detector 180. The R / W channel 40C is electrically connected to the write operation determination unit 620D (HDC 60D) via the transmission path WR1. Alternatively, the R / W channel 40C may not be connected to the write operation determination unit 620D (HDC 60D) via the transmission path WR1. The R / W channel 40C includes a write inhibit unit 410C.

[0309] The write inhibit unit 410C inhibits (or stops) writing (or writing operations) by the heads HD20 and HD21 via the HDCs 60C and 60D. The write inhibit unit 410C is connected to the write operation determination unit 620D (HDC 60D) via the transmission path WR1. Alternatively, the write inhibit unit 410C may not be connected to the write operation determination unit 620D (HDC 60D) via the transmission path WR1. The write inhibit unit 410C includes a vibration sensor write inhibit determination unit 411C, a first HDC write inhibit determination unit 412C, and a second HDC write inhibit determination unit 413C.

[0310] When the vibration sensor 170 detects vibration or shock, the vibration sensor write inhibition determination unit 411C determines whether to determine inhibition (or stop) of writing (or writing operation) by the head HD20 or not.

[0311] For example, upon receiving a write inhibit determination execution signal, the vibration sensor write inhibit determination unit 411C determines whether the vibration or shock is greater than a predetermined value via the head HD20 based on the write inhibit determination execution signal. For example, if it is determined that the vibration or shock is greater than the predetermined value, the vibration sensor write inhibit determination unit 411C determines to inhibit (or stop) writing (or a write operation) to the head HD20. For example, if it is determined that the vibration or shock is greater than the predetermined value, the vibration sensor write inhibit determination unit 411C outputs a write inhibit determination signal to determine that writing (or a write operation) to the head HD20 is prohibited (or stopped). For example, if it is determined that the vibration or shock is below the predetermined value, the vibration sensor write inhibit determination unit 411C does not determine to inhibit (or stop) writing (or a write operation) to the head HD20.

[0312] The first HDC write inhibit determination unit 412C inhibits (or stops) writing (or the writing operation) of the head HD20 corresponding to the HDC 60C. For example, upon receiving a write inhibit signal from the HDC 60C to inhibit (or stop) writing (or the writing operation) of the head HD20, the first HDC write inhibit determination unit 412C negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or the writing operation) of the head HD20. In other words, upon receiving a write inhibit signal from the HDC 60C to inhibit (or stop) writing (or the writing operation) of the head HD20 and vibration detection information indicating that the head HD20 is vibrating, the first HDC write inhibit determination unit 412C negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or the writing operation) of the head HD20.

[0313] For example, upon receiving a write inhibit signal for writing (or a write operation) to the head HD21 corresponding to the HDC 60D, the first HDC write inhibit determination unit 412C negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or a write operation) to the head HD20. In other words, upon receiving vibration detection information including a write inhibit signal for writing (or a write operation) to the head HD21 corresponding to the HDC 60D and indicating that the head HD21 is vibrating, the first HDC write inhibit determination unit 412C negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or a write operation) to the head HD20.

[0314] The second HDC write inhibit determination unit 413C inhibits (or stops) writing (or writing operation) to the head HD21 corresponding to the HDC 60D. For example, upon receiving a write inhibit signal from the HDC 60C for writing (or writing operation) to the head HD21, the second HDC write inhibit determination unit 413C outputs the write inhibit signal to the second HDC write inhibit determination unit 413D of the R / W channel 40D via the HDC 60C and the transmission path WR0. The write strobe is negated (negate or deassert) via the second HDC write inhibit determination unit 413D, thereby inhibiting (or stopping) writing (or writing operation) to the head HD21. In other words, when receiving a write inhibit signal including writing (or writing action) of the head HD21 from the HDC60C and vibration detection information indicating that the head HD21 is subjected to vibration, the second HDC write inhibit determination unit 413C outputs the vibration detection information to the second HDC write inhibit determination unit 413D of the R / W channel 40D via the HDC60C and the transmission path WR0, and invalidates (negates or deasserts) the write enable via the second HDC write inhibit determination unit 413D, thereby inhibiting (or stopping) writing (or writing action) of the head HD21.

[0315] For example, when receiving a write inhibit signal for writing (or writing action) of head HD21 from HDC60C, the second HDC write inhibit determination unit 413C outputs a signal to inhibit writing (or writing action) of head HD21 to HDC60C, outputs the write inhibit signal to the second HDC write inhibit determination unit 413D of the R / W channel 40D via HDC60C and the transmission path WR0, and invalidates the write enable (negate or deassert) via the second HDC write inhibit determination unit 413D, thereby inhibiting (or stopping) writing (or writing action) of head HD21. In other words, when receiving a write inhibit signal including writing (or writing action) of the head HD21 from the HDC60C and vibration detection information indicating that the head HD21 is subjected to vibration, the second HDC write inhibit determination unit 413C outputs a signal to inhibit writing (or writing action) of the head HD21 to the HDC60C, outputs the vibration detection information to the second HDC write inhibit determination unit 413D of the R / W channel 40D via the HDC60C and the transmission path WR0, and invalidates (negates or deasserts) the write enable via the second HDC write inhibit determination unit 413D, thereby inhibiting (or stopping) writing (or writing action) of the head HD21.

[0316] For example, when receiving a write inhibit signal for writing (or writing action) of head HD21 from HDC60C, the second HDC write inhibit determination unit 413C outputs the write inhibit signal to the second HDC write inhibit determination unit 413D of the R / W channel 40D via the transmission path WR1 and HDC60D, and invalidates (negates or deasserts) the write enable via the second HDC write inhibit determination unit 413D, thereby inhibiting (or stopping) writing (or writing action) of head HD21. In other words, when receiving a write inhibit signal including writing (or writing action) of the head HD21 from HDC60C and vibration detection information indicating that the head HD21 is subjected to vibration, the second HDC write inhibit determination unit 413C outputs the vibration detection information to the second HDC write inhibit determination unit 413D of the R / W channel 40D via the transmission path WR1 and HDC60D, and invalidates (negates or deasserts) the write enable via the second HDC write inhibit determination unit 413D, thereby inhibiting (or stopping) writing (or writing action) of the head HD21.

[0317] For example, when receiving a write inhibit signal for writing (or writing action) of head HD21 from HDC60C, the second HDC write inhibit determination unit 413C outputs a signal for inhibiting writing (or writing action) of head HD21 to HDC60D, and outputs the write inhibit signal to the second HDC write inhibit determination unit 413D of the R / W channel 40D via the transmission path WR1 and HDC60D, and invalidates the write enable (negate or deassert) via the second HDC write inhibit determination unit 413D, thereby inhibiting (or stopping) writing (or writing action) of head HD21. In other words, when receiving a write inhibit signal including writing (or writing action) of the head HD21 and vibration detection information indicating that the head HD21 is subjected to vibration from the HDC60C, the second HDC write inhibit determination unit 413C outputs a signal to inhibit writing (or writing action) of the head HD21 to the HDC60D, outputs the vibration detection information to the second HDC write inhibit determination unit 413D of the R / W channel 40D via the transmission path WR1 and HDC60D, and invalidates (negates or deasserts) the write enable via the second HDC write inhibit determination unit 413D, thereby inhibiting (or stopping) writing (or writing action) of the head HD21.

[0318] The MPU 50C controls the actuator AC2 and MA1620 via the driver IC 20C, performing servo control for positioning the head HD20. The MPU 50C controls the writing of data to the top surface FS2 of the disk DK2 and selects the storage destination for the written data. Furthermore, the MPU 50C controls the reading of data from the top surface FS2 of the disk DK2 and controls the processing of the read data. The MPU 50C is connected to various components of the magnetic disk drive 1. For example, the MPU 50C is electrically connected to the driver IC 20C, the R / W channel 40C, and the HDC 60C.

[0319] The HDC 60C controls read / write processing based on instructions from the MPU 50C, controlling data transfer between the host computer 700 and the R / W channel 40C. The HDC 60C is electrically connected to, for example, the R / W channel 40C, the MPU 50C, the volatile memory 70, the buffer memory 80, and the nonvolatile memory 90. The HDC 60C is electrically connected to the R / W channel 40D via the transmission path WR0. Alternatively, the HDC 60C may not be connected to the R / W channel 40D via the transmission path WR0.

[0320] The HDC60C includes a servo control unit 610C and a write operation determination unit 620C. The HDC60C executes the processing of each of the aforementioned units, such as the servo control unit 610C and the write operation determination unit 620C, in firmware. Furthermore, the HDC60C may include each of the aforementioned units as circuits. Furthermore, a portion of the HDC60C configuration may be provided in the MPU50C. For example, the servo control unit 610C and the write operation determination unit 620C may also be provided in the MPU50C. The HDC60C prohibits (or stops) the write operation of the head HD20. For example, upon receiving a write prohibition signal, the HDC60C prohibits (or stops) the write operation of the head HD20.

[0321] The servo control unit 610C controls the position of the head HD20. In other words, the servo control unit 610C controls access to a predetermined area of ​​the top surface FS2 of the disk DK2 by the head HD20. The servo control unit 610C includes a tracking control unit 611C and a seek control unit 612C.

[0322] The tracking control unit 611C controls the head HD20 to track a predetermined track on the top surface FS2 of the disk DK2. The tracking control unit 611C includes a DPES demodulator 6111C. Alternatively, the tracking control unit 611C may include an SPES demodulator.

[0323] The DPES demodulation unit 6111C reads the data sector DS on the top surface FS2 of the disk DK2 and demodulates the DPES.

[0324] The seek control unit 612C controls the head HD20 to seek from a predetermined track to a target track on the top surface FS2 of the disk DK2.

[0325] The write operation determination unit 620C is connected to the R / W channel 40D via the wiring WR0. Alternatively, the write operation determination unit 620C may not be connected to the R / W channel 40D via the wiring WR0. The write operation determination unit 620C includes a position write operation determination unit 621C and a speed write operation determination unit 622C. The position write operation determination unit 621C determines the write operation of the head HD20 based on the position of the head HD20. The speed write operation determination unit 622C determines the write operation of the head HD20 based on the speed of the head HD20.

[0326] The write operation determination unit 620C determines whether or not to prohibit (or stop) writing (or the write operation) of the head HD20 corresponding to the HDC 60C.

[0327] When receiving a write prohibition determination signal (or write prohibition determination information) for writing (or writing action) by the head HD20 corresponding to HDC60C, the write action determination unit 620C determines whether to prohibit (or stop) writing (or writing action) by the head HD20 based on the SPES demodulated by reading from the servo sector SS of the disk DK2 or the DPES demodulated by reading from the data sector DS by the head HD20.

[0328] Upon receiving a write inhibit determination signal (or write inhibit determination information) for writing (or a write operation) of the head HD20 corresponding to the HDC 60C, the write operation determination unit 620C determines whether the SPES or DPES corresponding to the head HD20 exceeds a threshold value.

[0329] When determining that the SPES or DPES corresponding to head HD20 exceeds the threshold, the write operation determination unit 620C determines to prohibit (or stop) writing (or writing operation) of head HD20 and outputs a write prohibition signal to the R / W channel 40C corresponding to HDC60C.

[0330] When receiving a signal from the second HDC write inhibit determination unit 413C to inhibit writing (or a write operation) to the head HD21 corresponding to the HDC 60D, the write operation determination unit 620C may output a write inhibit signal to the R / W channel 40D. When receiving a signal from the second HDC write inhibit determination unit 413C to inhibit writing (or a write operation) to the head HD21 corresponding to the HDC 60D, the write operation determination unit 620C may output a write inhibit signal to the R / W channel 40D via the transmission path WR0.

[0331] In addition, when receiving a signal from the second HDC write prohibition determination unit 413C to prohibit writing (or writing action) of the head HD21 corresponding to HDC60D, the write action determination unit 620C may also not output a write prohibition signal to the R / W channel 40D based on the status of the system controller 130D, the head HD21, etc.

[0332] For example, when determining that the SPES or DPES corresponding to the head HD20 exceeds the threshold, the write operation determination unit 620C may output a write inhibit signal to the R / W channel 40D.

[0333] For example, when the SPES or DPES corresponding to the head HD20 is determined to be below the threshold, the write operation determination unit 620C prohibits (or stops) writing (or writing operation) by the head HD20 without passing through the HDC 60C. In other words, when the SPES or DPES corresponding to the head HD20 is determined to be below the threshold, the write operation determination unit 620C continues (or continues) writing (or writing operation) by the head HD20.

[0334] The system controller 130D includes an R / W channel 40D, an MPU 50D, and an HDC 60D. The system controller 130D is electrically connected to the driver IC 20D, the head amplifier IC 30D, the write disable detector 180, the controller communication unit 190, and the host system 700. The system controller 130D is electrically connected to the system controller 130C via transmission paths WR0 and WR1. The system controller 130D may also include an SPM control unit 210D, a VCM control unit 220D, and an MA control unit 230D. The system controller 130D may also include a driver IC 20D and a head amplifier IC 30D.

[0335] The R / W channel 40D performs signal processing for read data transmitted from the lower surface RS2 of the disk DK2 to the host computer 700, and for write data transmitted from the host computer 700, based on instructions from the MPU 50D. The R / W channel 40D is electrically connected to, for example, the head amplifier IC 30D, the MPU 50D, the HDC 60D, and the write inhibit detector 180. The R / W channel 40D is electrically connected to the write operation determination unit 620C (HDC 60C) via the transmission path WR0. Alternatively, the R / W channel 40D may not be connected to the write operation determination unit 620C (HDC 60C) via the transmission path WR0. The R / W channel 40D includes a write inhibit unit 410D.

[0336] The write inhibit unit 410D inhibits (or stops) writing (or writing operations) by the heads HD20 and HD21 via the HDCs 60C and 60D. The write inhibit unit 410D is connected to the write operation determination unit 620C (HDC 60C) via the transmission path WR0. Alternatively, the write inhibit unit 410D may not be connected to the write operation determination unit 620C (HDC 60C) via the transmission path WR0. The write inhibit unit 410D includes a vibration sensor write inhibit determination unit 411D, a first HDC write inhibit determination unit 412D, and a second HDC write inhibit determination unit 413D.

[0337] The vibration sensor write inhibition determination unit 411D determines whether to determine inhibition (or stop) of writing (or writing operation) by the head HD21 or not to determine inhibition (or stop) of writing (or writing operation) when vibration or shock is detected by the vibration sensor 170 .

[0338] For example, upon receiving a write inhibit determination execution signal, the vibration sensor write inhibit determination unit 411D determines whether the vibration or shock is greater than a predetermined value via the head HD21 based on the write inhibit determination execution signal. For example, upon determining that the vibration or shock is greater than the predetermined value, the vibration sensor write inhibit determination unit 411D determines to inhibit (or stop) writing (or a write operation) to the head HD21. For example, upon determining that the vibration or shock is greater than the predetermined value, the vibration sensor write inhibit determination unit 411D outputs a write inhibit determination signal to determine to inhibit (or stop) writing (or a write operation) to the head HD21. For example, upon determining that the vibration or shock is below the predetermined value, the vibration sensor write inhibit determination unit 411D does not determine to inhibit (or stop) writing (or a write operation) to the head HD21.

[0339] The first HDC write inhibit determination unit 412D inhibits (or stops) writing (or a write operation) to the head HD20 corresponding to the HDC 60C. For example, upon receiving a write inhibit signal from the HDC 60D to inhibit (or stop) writing (or a write operation) to the head HD20, the first HDC write inhibit determination unit 412D outputs the write inhibit signal to the first HDC write inhibit determination unit 412C of the R / W channel 40C via the HDC 60D and the transmission path WR1. The write strobe is negated (negate or deassert) via the first HDC write inhibit determination unit 412C, thereby inhibiting (or stopping) writing (or a write operation) to the head HD20. In other words, when receiving a write inhibit signal including a signal for inhibiting (or stopping) writing (or writing action) of the head HD20 from the HDC60D and vibration detection information indicating that the head HD20 is subjected to vibration, the first HDC write inhibit determination unit 412D outputs the vibration detection information to the first HDC write inhibit determination unit 412C of the R / W channel 40C via the HDC60D and the transmission path WR1, and invalidates (negates or deasserts) the write enable via the first HDC write inhibit determination unit 412C, thereby inhibiting (or stopping) writing (or writing action) of the head HD20.

[0340] For example, when receiving a write inhibit signal for writing (or writing action) of the head HD20 from the HDC60D, the first HDC write inhibit determination unit 412D outputs a signal for inhibiting writing (or writing action) of the head HD20 to the HDC60D, outputs the write inhibit signal to the first HDC write inhibit determination unit 412C of the R / W channel 40C via the HDC60D and the transmission path WR1, and invalidates the write enable (negate or deassert) via the first HDC write inhibit determination unit 412C, thereby inhibiting (or stopping) writing (or writing action) of the head HD20. In other words, when receiving a write inhibit signal including writing (or writing action) of the head HD20 from the HDC60D and vibration detection information indicating that the head HD20 is subjected to vibration, the first HDC write inhibit determination unit 412D outputs a signal to inhibit writing (or writing action) of the head HD20 to the HDC60D, outputs the vibration detection information to the first HDC write inhibit determination unit 412C of the R / W channel 40C via the HDC60D and the transmission path WR1, and invalidates the write enable (negate or deassert) via the first HDC write inhibit determination unit 412C, thereby inhibiting (or stopping) writing (or writing action) of the head HD20.

[0341] For example, when receiving a write inhibit signal for writing (or writing action) of the head HD20 from HDC60D, the first HDC write inhibit determination unit 412D outputs the write inhibit signal to the first HDC write inhibit determination unit 412C of the R / W channel 40C via the transmission path WR0 and HDC60C, and invalidates (negates or deasserts) the write enable via the first HDC write inhibit determination unit 412C, thereby inhibiting (or stopping) the writing (or writing action) of the head HD20. In other words, when receiving a write inhibit signal including a signal for inhibiting (or stopping) writing (or writing action) of the head HD20 from the HDC60D and vibration detection information indicating that the head HD20 is subjected to vibration, the first HDC write inhibit determination unit 412D outputs the vibration detection information to the first HDC write inhibit determination unit 412C of the R / W channel 40C via the transmission path WR0 and the HDC60C, and invalidates (negates or deasserts) the write enable via the first HDC write inhibit determination unit 412C, thereby inhibiting (or stopping) writing (or writing action) of the head HD20.

[0342] For example, when receiving a write inhibit signal for writing (or writing action) of head HD20 from HDC60D, the first HDC write inhibit determination unit 412D outputs a signal for inhibiting writing (or writing action) of head HD20 to HDC60C, and outputs the write inhibit signal to the first HDC write inhibit determination unit 412C of the R / W channel 40C via the transmission path WR0 and HDC60C, and invalidates the write enable (negate or deassert) via the first HDC write inhibit determination unit 412C, thereby inhibiting (or stopping) writing (or writing action) of head HD20. In other words, when receiving a write inhibit signal including writing (or writing action) of the head HD20 from HDC60D and vibration detection information indicating that the head HD20 is subjected to vibration, the first HDC write inhibit determination unit 412D outputs a signal to inhibit writing (or writing action) of the head HD20 to HDC60C, outputs the vibration detection information to the first HDC write inhibit determination unit 412C of the R / W channel 40C via the transmission path WR0 and HDC60C, and invalidates (negates or deasserts) the write enable via the first HDC write inhibit determination unit 412C, thereby inhibiting (or stopping) writing (or writing action) of the head HD20.

[0343] The second HDC write inhibit determination unit 413D inhibits (or stops) writing (or the writing operation) to the head HD21 corresponding to the HDC 60D. For example, upon receiving a write inhibit signal from the HDC 60D regarding writing (or the writing operation) to the head HD21, the second HDC write inhibit determination unit 413D negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or the writing operation) to the head HD21. In other words, upon receiving a write inhibit signal from the HDC 60D regarding writing (or the writing operation) to the head HD21 and vibration detection information indicating that the head HD21 is vibrating, the second HDC write inhibit determination unit 413D negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or the writing operation) to the head HD21.

[0344] For example, upon receiving a write inhibit signal for writing (or a write operation) to head HD20 corresponding to HDC 60C, the second HDC write inhibit determination unit 413D negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or a write operation) to head HD21. In other words, upon receiving vibration detection information including a write inhibit signal for writing (or a write operation) to head HD20 corresponding to HDC 60C and indicating that head HD20 is vibrating, the second HDC write inhibit determination unit 413D negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or a write operation) to head HD21.

[0345] The MPU 50D controls the actuator AC2 and MA1621 via the driver IC 20D, performing servo control for positioning the head HD21. The MPU 50D controls the writing of data to the lower surface RS2 of the disk DK2 and selects the storage destination for the written data. Furthermore, the MPU 50D controls the reading of data from the lower surface RS2 of the disk DK2 and controls the processing of the read data. The MPU 50D is connected to various components of the magnetic disk drive 1. For example, the MPU 50D is electrically connected to the driver IC 20D, the R / W channel 40D, and the HDC 60D.

[0346] The HDC 60D controls read / write processing based on instructions from the MPU 50D, controlling data transfer between the host computer 700 and the R / W channel 40D. The HDC 60D is electrically connected to, for example, the R / W channel 40D and the MPU 50D. The HDC 60D is electrically connected to the R / W channel 40C via the transmission path WR1. However, the HDC 60D does not necessarily need to be connected to the R / W channel 40C via the transmission path WR1.

[0347] The HDC60D includes a servo control unit 610D and a write operation determination unit 620D. The HDC60D executes the processing of each of the aforementioned units, such as the servo control unit 610D and the write operation determination unit 620D, in firmware. Furthermore, the HDC60D may include each of the aforementioned units as circuits. Furthermore, a portion of the HDC60D configuration may be provided in the MPU50D. For example, the servo control unit 610D and the write operation determination unit 620D may also be provided in the MPU50D. The HDC60D prohibits (or stops) the write operation of the head HD21. For example, upon receiving a write prohibition signal, the HDC60D prohibits (or stops) the write operation of the head HD21.

[0348] The servo control unit 610D controls the position of the head HD21. In other words, the servo control unit 610D controls access to a predetermined area of ​​the lower surface RS2 of the disk DK2 by the head HD21. The servo control unit 610D includes a tracking control unit 611D and a seek control unit 612D.

[0349] The tracking control unit 611D controls the head HD21 to track a predetermined track on the lower surface RS2 of the disk DK2. The tracking control unit 611D includes a DPES demodulator 6111D. Alternatively, the tracking control unit 611D may include an SPES demodulator.

[0350] The DPES demodulation unit 6111D reads the data sector DS on the lower surface RS2 of the disk DK2 and demodulates the DPES.

[0351] The seek control unit 612D controls the head HD21 to seek from a predetermined track to a target track on the lower surface RS2 of the disk DK2.

[0352] The write operation determination unit 620D is connected to the R / W channel 40C via the wiring WR1. Alternatively, the write operation determination unit 620D may not be connected to the R / W channel 40C via the wiring WR1. The write operation determination unit 620D includes a position write operation determination unit 621D and a speed write operation determination unit 622D. The position write operation determination unit 621D determines the write operation of the head HD21 based on the position of the head HD21. The speed write operation determination unit 622D determines the write operation of the head HD21 based on the speed of the head HD21.

[0353] The write operation determination unit 620D determines whether or not to prohibit (or stop) writing (or the write operation) of the head HD21 corresponding to the HDC 60D.

[0354] When receiving a write prohibition determination signal (or write prohibition determination information) for writing (or writing action) by the head HD21 corresponding to HDC60D, the write action determination unit 620D determines whether to prohibit (or stop) writing (or writing action) by the head HD21 based on the SPES demodulated by reading from the servo sector SS of the disk DK2 or the DPES demodulated by reading from the data sector DS by the head HD21.

[0355] Upon receiving a write inhibit determination signal (or write inhibit determination information) for writing (or writing operation) of the head HD21 corresponding to the HDC 60D, the write operation determination unit 620D determines whether the SPES or DPES corresponding to the head HD21 exceeds a threshold value.

[0356] When it is determined that the SPES or DPES corresponding to the head HD21 exceeds the threshold, the write operation determination unit 620D determines to prohibit (or stop) the writing (or writing operation) of the head HD21 and outputs a write prohibition signal to the R / W channel 40D corresponding to the HDC60D.

[0357] When receiving a signal from the first HDC write inhibit determination unit 412D to inhibit writing (or a write operation) to the head HD20 corresponding to the HDC 60C, the write operation determination unit 620D may output a write inhibit signal to the R / W channel 40C. When receiving a signal from the first HDC write inhibit determination unit 412D to inhibit writing (or a write operation) to the head HD20 corresponding to the HDC 60C, the write operation determination unit 620D may output a write inhibit signal to the R / W channel 40C via the transmission path WR1.

[0358] In addition, when receiving a signal from the first HDC write prohibition determination unit 412D to prohibit writing (or writing action) of the head HD20 corresponding to the HDC 60C, the write action determination unit 620D may not output a write prohibition signal to the R / W channel 40C according to the status of the system controller 130C, the head HD20, etc.

[0359] For example, when determining that the SPES or DPES corresponding to the head HD21 exceeds the threshold, the write operation determination unit 620D may output a write inhibit signal to the R / W channel 40C.

[0360] For example, when the SPES or DPES corresponding to the head HD21 is determined to be below the threshold, the write operation determination unit 620D prohibits (or stops) writing (or writing operation) by the head HD21 without passing through the HDC 60D. In other words, when the SPES or DPES corresponding to the head HD21 is determined to be below the threshold, the write operation determination unit 620D continues (or continues) writing (or writing operation) by the head HD21.

[0361] Figure 17 This is a flowchart showing an example of a method for stopping a write operation according to the second embodiment.

[0362] The system controller 130 reads a data sector with a predetermined head HD (B1401), demodulates and obtains a DPES based on predetermined information (or predetermined data) in the data sector (B1402). The system controller 130 determines whether the current position error corresponding to the predetermined head HD is greater than a threshold for stopping the head HD (B1403).

[0363] If the system controller 130 determines that the current position error corresponding to the designated head HD is below the threshold (B1403: No), the system controller 130 determines whether the next position error of the designated head HD is greater than the threshold for stopping the head HD (B1404). If the next position error is determined to be below the threshold (B1404: No), the system controller 130 proceeds to the process of B1401. If the next position error is determined to be greater than the threshold (B1404: Yes), the system controller 130 proceeds to the process of B1705.

[0364] When it is determined that the current position error corresponding to the predetermined head HD is greater than the threshold value (B1403: Yes), the system controller 130 stops (prohibits) the writing action of the predetermined head HD (B1705), and also stops (prohibits) the writing action of other heads HD different from the predetermined head HD (B1706), and ends the processing.

[0365] According to the second embodiment, when the magnetic disk device 1 stops (prohibits) the writing operation of a predetermined head HD, it can also stop (prohibit) the writing operation of other heads HD. Therefore, the magnetic disk device 1 can improve formatting efficiency.

[0366] (Variation 2)

[0367] The configuration of the magnetic disk device 1 according to the second modification of the second embodiment is different from the configuration of the magnetic disk device 1 according to the second embodiment.

[0368] Figure 18 This is a schematic diagram showing an example of the configuration of the magnetic disk device 1 according to Modification 2.

[0369] exist Figure 18 In the illustrated example, the write inhibit section 410C includes a vibration sensor write inhibit determination section 411C and a first HDC write inhibit determination section 412C.

[0370] The write operation determination unit 620C further includes a PES write operation determination unit 623C. The PES write operation determination unit 623C determines whether to prohibit (or stop) writing (or the write operation) by the head HD21 (write head WH21) based on the SPES or DPES demodulated by reading the servo sector SV or the data sector DS of the lower surface RS2 of the disk DK2 via the HDC 60D by the head HD21 (read head RH21) corresponding to the HDC 60D.

[0371] For example, upon receiving a write-inhibit signal that inhibits (or stops) writing (or a write operation) by head HD20, the PES write operation determination unit 623C outputs a write-inhibit signal that inhibits (or stops) writing (or a write operation) by head HD21 (write head WH21) to the R / W channel 40D via the write-inhibit information transmission unit 1911 and the HDC 60D. In other words, upon receiving vibration detection information that includes a write-inhibit signal that inhibits (or stops) writing (or a write operation) by head HD20 and indicates that head HD20 is vibrating, the PES write operation determination unit 623C outputs vibration detection information that inhibits (or stops) writing (or a write operation) by head HD21 (write head WH21) to the R / W channel 40D via the write-inhibit information transmission unit 1911 and the HDC 60D.

[0372] Furthermore, upon receiving a write-inhibit signal for inhibiting (or stopping) writing (or a write operation) by the head HD20, the PES write operation determination unit 623C may not output the write-inhibit signal for inhibiting (or stopping) writing (or a write operation) by the head HD21 (write head WH21) to the R / W channel 40D, depending on the status of the system controller 130D or the head HD21. In other words, upon receiving vibration detection information including a write-inhibit signal for inhibiting (or stopping) writing (or a write operation) by the head HD20 and indicating that the head HD20 is vibrating, the PES write operation determination unit 623C may not output vibration detection information for inhibiting (or stopping) writing (or a write operation) by the head HD21 (write head WH21) to the R / W channel 40D, depending on the status of the system controller 130D or the head HD21.

[0373] The write inhibit section 410D includes a vibration sensor write inhibit determination section 411D and a second HDC write inhibit determination section 413D.

[0374] The write operation determination unit 620D further includes a PES write operation determination unit 623D. The PES write operation determination unit 623D determines whether to prohibit (or stop) writing (or a write operation) by the head HD20 (write head WH20) based on the SPES or DPES demodulated by reading the servo sector SV or the data sector DS of the upper surface FS2 of the disk DK2 via the HDC 60C by the head HD20 (read head RH20) corresponding to the HDC 60C.

[0375] For example, upon receiving a write-inhibit signal that inhibits (or stops) writing (or a write operation) by head HD21, the PES write operation determination unit 623D outputs the write-inhibit signal that inhibits (or stops) writing (or a write operation) by head HD20 (write head WH20) to the R / W channel 40C via the write-inhibit information transmission unit 1911 and the HDC 60C. In other words, upon receiving vibration detection information that includes a write-inhibit signal that inhibits (or stops) writing (or a write operation) by head HD21 and indicates that head HD21 is vibrating, the PES write operation determination unit 623D outputs vibration detection information that inhibits (or stops) writing (or a write operation) by head HD20 (write head WH20) to the R / W channel 40C via the write-inhibit information transmission unit 1911 and the HDC 60C.

[0376] Furthermore, upon receiving a write-inhibit signal for inhibiting (or stopping) writing (or a write operation) by the head HD21, the PES write operation determination unit 623D may not output the write-inhibit signal for inhibiting (or stopping) writing (or a write operation) by the head HD20 (write head WH20) to the R / W channel 40C, depending on the status of the system controller 130C or the head HD20. In other words, upon receiving vibration detection information including a write-inhibit signal for inhibiting (or stopping) writing (or a write operation) by the head HD21 and indicating that the head HD21 is vibrating, the PES write operation determination unit 623D may not output vibration detection information for inhibiting (or stopping) writing (or a write operation) by the head HD20 (write head WH20) to the R / W channel 40C, depending on the status of the system controller 130C or the head HD20.

[0377] According to variation 2, the magnetic disk drive 1 further includes a write-inhibit information transmission unit 1911. When the current position error of a predetermined head HD exceeds a threshold for stopping (or inhibiting) the write operation of the predetermined head HD, the predetermined system controller 130 stops (or inhibits) the write operation by the predetermined head HD. When stopping (or inhibiting) the write operation by the predetermined head HD, the predetermined system controller 130 can also stop (or inhibit) the write operation by other heads HD corresponding to other system controllers 130 among the multiple system controllers 130. For example, the predetermined system controller 130 stops (or inhibits) the write operation by the other heads HD by outputting a write-inhibit signal (or vibration detection information) to the other system controllers 130 via the write-inhibit information transmission unit 1911. Therefore, the magnetic disk drive 1 can improve formatting efficiency.

[0378] (Third embodiment)

[0379] The configuration of the magnetic disk device 1 according to the third embodiment is different from the configurations of the magnetic disk devices 1 according to the aforementioned embodiment and the aforementioned modified examples.

[0380] The magnetic disk device 1 according to the third embodiment is a two-dimensional magnetic recording (TDMR) magnetic disk device having a plurality of read heads on its head.

[0381] Figure 19 It is a schematic diagram showing an example of the configuration of the magnetic disk device 1 according to the third embodiment.

[0382] exist Figure 19 In the example shown, disk DK includes disk DK3. Disk DK3 is mounted on spindle 12. Disk DK3 includes an upper surface FS3 and a lower surface RS3 opposite to upper surface FS3. Disk DK3 may include two or more disks.

[0383] The head HD includes a head HD3. The head HD3 includes a head HD30 that faces the upper surface FS3 of the disk DK3, and a head HD31 that faces the lower surface RS3 of the disk DK3. Furthermore, the head HD3 may include only one head or three or more heads. The head HD3 includes a write head WH3 that writes data to the disk DK3, and a read head RH3 that reads the data written to the disk DK3. The write head WH3 includes a write head WH30 and a write head WH31. The read head RH3 includes a read head RH30 and a read head RH31. The read head RH30 includes a read head RH300 and a read head RH301. The read head RH31 includes a read head RH310 and a read head RH311.

[0384] The head HD30 includes a write head WH30 for writing data to the top surface FS3 of the disk DK3, and multiple read heads RH30 (RH300, RH301) for reading the data written to the top surface FS3 of the disk DK3. The read head RH300 is, for example, located in the head HD30 at the position farthest from the write head WH30. The read head RH301 is, for example, located immediately behind the read head RH300 and further away from the write head WH30. In other words, the read head RH301 is positioned between the write head WH30 and the read head RH300. Alternatively, the read head RH300 may include three or more read heads.

[0385] The head HD31 includes a write head WH30 for writing data to the lower surface RS3 of the disk DK3, and multiple read heads RH30 (RH300, RH301) for reading the data written to the lower surface RS3 of the disk DK3. The read head RH300 is, for example, located in the head HD30 at the position farthest from the write head WH30. The read head RH301 is, for example, located immediately below the read head RH300 and further away from the write head WH30. In other words, the read head RH301 is positioned between the write head WH30 and the read head RH300. Alternatively, the read head RH31 may include three or more read heads.

[0386] The actuator block BK includes an actuator block BK3 .

[0387] The arm AM includes an arm AM3. The arm AM3 may also include an arm AM30 located on the upper surface FS3 side of the disk DK3 and an arm AM31 located on the lower surface RS3 side of the disk DK3. Furthermore, the arm AM3 may include only one arm or three or more arms, depending on the number of heads HD3. The arm AM3 is connected to the actuator block BK3.

[0388] The VCM 14 includes a VCM 143. The VCM 143 is connected to the actuator block BK3 on the side opposite to the arm AM3.

[0389] The suspension 15 has a suspension 153. The suspension 153 is mounted on the arm AM3. The suspension 153 is equipped with a head HD3 at the top end portion on the side opposite to the end portion connected to the arm AM3. The suspension 153 has a suspension 1530 mounted on the arm AM30 and a suspension 1531 mounted on the arm AM31. In addition, the suspension 153 may have only one suspension or three or more suspensions depending on the number of arms AM3. The suspension 1530 is equipped with a head HD30 at the top end portion on the side opposite to the end portion connected to the arm AM30. The suspension 1531 is equipped with a head HD31 at the top end portion on the side opposite to the end portion connected to the arm AM31.

[0390] The MA163 includes an MA163. The MA163 is mounted on the suspension 153. Compared to the VCM 143's control of the radial motion of the head HD3, the MA163 provides more precise control of the radial motion of the head HD3. For example, the MA163 includes an MA1630 mounted on the suspension 1530 and an MA1631 mounted on the suspension 1531. Depending on the number of suspensions 153, the MA163 can include only one or three or more MAs.

[0391] The MA 1630 finely controls the radial motion of the head HD 30. For example, compared to the VCM 143's control of the radial motion of the head HD 30, the MA 1630 controls the radial motion of the head HD 30 more finely. The MA 1631 finely controls the radial motion of the head HD 31. For example, compared to the VCM 143's control of the radial motion of the head HD 31, the MA 1631 controls the radial motion of the head HD 31 more finely. For example, the MA 1630 and MA 1631 are driven independently of the VCM 143.

[0392] Actuator AC includes actuator AC3. Actuator AC3 is rotatably mounted on bearing BR2. Actuator AC3 consists of suspension 153, MA163, arm AM3, actuator block BK3, and VCM143. Actuator AC3 drives VCM143 around the rotation axis of bearing BR2 and precisely drives MA163, thereby positioning head HD3 mounted on suspension 153 at a predetermined position on disk DK3. If MA163 is not included, actuator AC3 drives VCM143 around bearing BR2, thereby positioning head HD3 mounted on suspension 153 at a predetermined position on disk DK3.

[0393] Figure 20 It is a plan view showing an example of the arrangement of the head HD relative to the disk DK according to the third embodiment.

[0394] The magnetic disk device 1 positions the head HD at a predetermined position or track on the disk DK using the read head RH30, the read head RH31, or the center portion between the read heads RH30 and RH31 as a reference.

[0395] exist Figure 20 In the example shown, the upper surface FS3 of the disk DK3 is allocated with a user data area DKa4 and a system area DKb4. The lower surface RS3 of the disk DK3 is allocated with a user data area DKa5 and a system area DKb5. The disk DK3 has a radial position RP0.

[0396] exist Figure 20In the example shown, during seek, the head HD3 slides within the horizontal plane of the disk DK3 as it rotates about the bearing BR2 via the actuator AC3. When the head HD3 is at radial position RP0, the skew angle of the head HD3 is, for example, 0 degrees. Hereinafter, radial position RP0 may also be referred to as reference position RP0. When the head HD3 is located outward or inward of radial position RP0, the absolute value of the skew angle is greater than 0 degrees.

[0397] Figure 21 This is a diagram showing an example of the geometric arrangement of the write head WH3 and the two read heads RH30 and RH31 when the read head RH30 is located at the radial position RP0.

[0398] Figure 21 The center WC (WC0, WC1) of the write head WH3 (WH30, WH31), the center RC0 (RC00, RC01) of the read head RH30 (RH300, RH301), and the center RC1 (RC10, RC11) of the read head RH31 (RH310, RH311) are shown. Figure 21 The figure shows the middle part HR (HR0, HR1) between the center part RC0 (RC00, RC01) of the read head RH30 (RH300, RH301) and the center part RC1 (RC10, RC11) of the read head RH31 (RH310, RH311). The circumferential distance between the center part RC0 of the read head RH30 and the center part RC1 of the read head RH31 is sometimes referred to as the down track separation (DTS). The radial distance between the center part RC0 of the read head RH30 and the center part RC1 of the read head RH31 is sometimes referred to as the cross track separation (CTS). The center part WC of the write head WH3 is perpendicular to the straight line passing through the center part RC0 of the read head RH30 and the center part RC1 of the read head RH31 by a distance OF0.

[0399] exist Figure 21 In the example shown, when read head RH30 is positioned at reference position RP0, read heads RH30, RH31, and intermediate portion HR are arranged in a straight line in the circumferential direction. When read head RH30 is positioned at reference position RP0, write head WH3 is radially spaced a distance OF0 from read heads RH30, RH31, and intermediate portion HR. Alternatively, when read head RH30 is positioned at reference position RP0, write head WH3, read heads RH30, RH31, and intermediate portion HR may be arranged in a straight line in the circumferential direction.

[0400] HD3 in maintenance Figure 21In the geometric configuration shown, the write head WH3 and the two read heads RH30 and RH31 are driven by the actuator AC3 or MA16 to move in the radial direction while being tilted at a predetermined angle.

[0401] Figure 22 This is a diagram showing an example of the geometric arrangement of the write head WH3 and the two read heads RH30 and RH31 when the read head RH30 is located at the radial position ORP. Figure 22 : shows the radial position ORP in the outward direction from the reference position RP0.

[0402] exist Figure 22 In the example shown, when read head RH30 is at radial position ORP, read heads RH30 and RH31 are separated by a cross-track spacing CTS1. When read head RH30 is at radial position ORP, read heads RH30 and RH31 are separated by an along-track spacing DTS1. When read head RH30 is at radial position ORP, head HD3 is tilted outward at a tilt angle θ1.

[0403] The driver IC 20 includes a driver IC 20E and a driver IC 20F. Driver ICs 20E and 20F are formed in separate configurations, such as separate circuits. Alternatively, driver ICs 20E and 20F may be formed in an integrated configuration, such as an integrated circuit. The SPM control unit 210 includes an SPM control unit 210E. The VCM control unit 220 includes a VCM control unit 220E. The MA control unit 230 includes MA control units 230E and 230F.

[0404] The driver IC 20E controls the driving of the SPM 13, VCM 143, and MA 1630 under the control of the system controller 130E (specifically, the MPU 50E or HDC 60E described later). The driver IC 20E is electrically connected to the SPM 13, driver IC 20F, VCM 143, and MA 1630. The driver IC 20E is connected to the SPM 13, driver IC 20E, VCM 143, and MA 1630, for example, via a predetermined interface.

[0405] The driver IC 20E includes an SPM control unit 210E, a VCM control unit 220E, and a microactuator (MA) control unit 230E. The SPM control unit 210E controls the rotation of the SPM 13. The VCM control unit 220E controls the drive of the VCM 143 by controlling the current (or voltage) supplied to the VCM 143. The MA control unit 230E controls the drive of the MA 1630 by controlling the current (or voltage) supplied to the MA 1630. Alternatively, a portion of the driver IC 20E components (e.g., the SPM control unit 210E, the VCM control unit 220E, and the MA control unit 230E) may be provided in the system controller 130E. If the actuator AC3 does not include the MA 1630, the MA control unit 230E may also be omitted.

[0406] The driver IC 20F controls the driving of the SPM 13, VCM 143, and MA 1631 under the control of the system controller 130F (specifically, the MPU 50F or HDC 60F described later). The driver IC 20F is electrically connected to the SPM 13, the driver IC 20E, the VCM 143, and the MA 1631. The driver IC 20F is connected to the SPM 13, the driver IC 20E, the VCM 143, and the MA 1631, for example, via a predetermined interface.

[0407] The driver IC 20F includes an MA control unit 230F. The SPM control unit 210F controls the rotation of the SPM 13. The VCM control unit 220F controls the drive of the VCM 143 by controlling the current (or voltage) supplied to the VCM 143. The MA control unit 230F controls the drive of the MA 1631 by controlling the current (or voltage) supplied to the MA 1631. Alternatively, a portion of the driver IC 20F (e.g., the MA control unit 230F) may be provided in the system controller 130F. If the actuator AC3 does not include the MA 1631, the MA control unit 230F may also be omitted.

[0408] The head amplifier IC30 includes a head amplifier IC30E and a head amplifier IC30F. The head amplifier IC30E and IC30F are formed in separate configurations, such as separate circuits. Alternatively, the head amplifier IC30E and IC30F may be formed in an integrated configuration, such as an integrated circuit. The head selector 310 includes head selectors 310E and 310F. The read signal detector 320 includes read signal detectors 320E and 320F.

[0409] The head amplifier IC30E amplifies the read signal received from the top surface FS3 of the disk DK3 and outputs it to the system controller 130E (specifically, the read / write (R / W) channel 40E described later). The head amplifier IC30E is electrically connected to the head HD30. Furthermore, the head amplifier IC30E outputs a write current to the head HD30 in response to the signal output from the R / W channel 40E.

[0410] The head amplifier IC 30E includes a head selector 310E and a read signal detector 320E. The head selector 310E selects the read head RH30 in the actuator AC3 to read data from the top surface FS3 of the disk DK3. The read signal detector 320E detects the signal (read signal) read by the read head RH30 from the top surface FS3 of the disk DK3. Alternatively, a portion of the components of the head amplifier IC 30E (e.g., the head selector 310E and the read signal detector 320E) may be provided in the system controller 130E.

[0411] The head amplifier IC30F amplifies the read signal received from the lower surface RS3 of the disk DK3 and outputs it to the system controller 130F (specifically, the read / write (R / W) channel 40F described later). The head amplifier IC30F is electrically connected to the head HD31. Furthermore, the head amplifier IC30F outputs a write current to the head HD31 in accordance with the signal output from the R / W channel 40F.

[0412] The head amplifier IC30F includes a head selector 310F and a read signal detector 320F. The head selector 310F selects the read head RH31 in the actuator AC3 to read data from the lower surface RS3 of the disk DK3. The read signal detector 320F selects the read head RH31 to read data from the lower surface RS3 of the disk DK3. The read signal detector 320F detects the signal (read signal) read by the read head RH31 from the lower surface RS3 of the disk DK3. Alternatively, a portion of the components of the head amplifier IC30F (e.g., the head selector 310F and the read signal detector 320F) may be provided in the system controller 130F.

[0413] The system controller 130 includes system controllers 130E and 130F. The system controllers 130E and 130F are formed in separate configurations, such as separate circuits. Alternatively, the system controllers 130E and 130F may be formed in an integrated configuration, such as an integrated circuit.

[0414] The R / W channel 40 includes R / W channels 40E and 40F. The vibration sensor write inhibit determination unit 411 includes vibration sensor write inhibit determination units 411E and 411F. The first HDC write inhibit determination unit 412 includes first HDC write inhibit determination units 412E and 412F. The second HDC write inhibit determination unit 413 includes second HDC write inhibit determination units 413E and 413F.

[0415] The MPU 50 includes MPUs 50E and 50F. The HDC 60 includes HDCs 60E and 60F. The servo control unit 610 includes servo control units 610E and 610F. The tracking control unit 611 includes tracking control units 611E and 611F. The DPES demodulation unit 6111 includes DPES demodulation units 6111E and 6111F. The seek control unit 612 includes seek control units 612E and 612F. The write action determination unit 620 includes write action determination units 620E and 620F. The position write action determination unit 621 includes position write action determination units 621E and 621F. The speed write action determination unit 622 includes speed write action determination units 622E and 622F.

[0416] The system controller 130E includes a R / W channel 40E, an MPU 50E, and an HDC 60E. The system controller 130E is electrically connected to the driver IC 20E, the head amplifier IC 30E, the volatile memory 70, the buffer memory 80, the non-volatile memory 90, the write inhibit detector 180, the controller communication unit 190, and the host system 700. The system controller 130E is electrically connected to the system controller 130E via transmission paths WR0 and WR1. Furthermore, the system controller 130E may include an SPM control unit 210E, a VCM control unit 220E, and an MA control unit 230E. The system controller 130E may also include the driver IC 20E and the head amplifier IC 30E.

[0417] The R / W channel 40E performs signal processing for read data transmitted from the top surface FS3 of the disk DK3 to the host 700, and for write data transmitted from the host 700, based on instructions from the MPU 50E. The R / W channel 40E is electrically connected to, for example, the head amplifier IC 30E, the MPU 50E, the HDC 60E, and the write inhibit detector 180. The R / W channel 40E is electrically connected to the write operation determination unit 620F (HDC 60F) via the transmission path WR1. Alternatively, the R / W channel 40E may not be connected to the write operation determination unit 620F (HDC 60F) via the transmission path WR1. The R / W channel 40E includes a write inhibit unit 410E.

[0418] The write inhibit unit 410E inhibits (or stops) writing (or writing operations) by the heads HD30 and HD31 via the HDCs 60E and 60F. The write inhibit unit 410E is connected to the write operation determination unit 620F (HDC 60F) via the transmission path WR1. Alternatively, the write inhibit unit 410E may not be connected to the write operation determination unit 620F (HDC 60F) via the transmission path WR1. The write inhibit unit 410E includes a vibration sensor write inhibit determination unit 411E, a first HDC write inhibit determination unit 412E, and a second HDC write inhibit determination unit 413E.

[0419] The vibration sensor write inhibition determination unit 411E determines whether to determine inhibition (or stop) of writing (or writing operation) by the head HD30 or not to determine inhibition (or stop) of writing (or writing operation) when the vibration sensor 170 detects vibration or shock.

[0420] For example, upon receiving a write inhibit determination execution signal, the vibration sensor write inhibit determination unit 411E determines whether the vibration or shock is greater than a predetermined value via the head HD30 based on the write inhibit determination execution signal. For example, if it is determined that the vibration or shock is greater than the predetermined value, the vibration sensor write inhibit determination unit 411E determines to inhibit (or stop) writing (or a writing operation) to the head HD30. For example, if it is determined that the vibration or shock is greater than the predetermined value, the vibration sensor write inhibit determination unit 411E outputs a write inhibit determination signal to determine that writing (or a writing operation) to the head HD30 is prohibited (or stopped). For example, if it is determined that the vibration or shock is below the predetermined value, the vibration sensor write inhibit determination unit 411E does not determine to inhibit (or stop) writing (or a writing operation) to the head HD30.

[0421] The first HDC write inhibit determination unit 412E inhibits (or stops) writing (or the writing operation) of the head HD30 corresponding to the HDC 60E. For example, upon receiving a write inhibit signal from the HDC 60E to inhibit (or stop) writing (or the writing operation) of the head HD30, the first HDC write inhibit determination unit 412E negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or the writing operation) of the head HD30. In other words, upon receiving a write inhibit signal from the HDC 60E to inhibit (or stop) writing (or the writing operation) of the head HD30 and vibration detection information indicating that the head HD30 is vibrating, the first HDC write inhibit determination unit 412E negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or the writing operation) of the head HD30.

[0422] For example, upon receiving a write inhibit signal that inhibits (or stops) writing (or a writing operation) by the head HD31 corresponding to the HDC 60E, the first HDC write inhibit determination unit 412E negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or a writing operation) by the head HD30. In other words, upon receiving vibration detection information including a write inhibit signal that inhibits (or stops) writing (or a writing operation) by the head HD31 corresponding to the HDC 60E and indicating that the head HD31 is vibrating, the first HDC write inhibit determination unit 412E negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or a writing operation) by the head HD30.

[0423] The second HDC write inhibit determination unit 413E inhibits (or stops) writing (or writing operation) to the head HD31 corresponding to the HDC 60F. For example, upon receiving a write inhibit signal from the HDC 60E for writing (or writing operation) to the head HD31, the second HDC write inhibit determination unit 413E outputs the write inhibit signal to the second HDC write inhibit determination unit 413F of the R / W channel 40F via the HDC 60E and the transmission path WR0. The write strobe is then negated or deasserted via the second HDC write inhibit determination unit 413F, thereby inhibiting (or stopping) writing (or writing operation) to the head HD31. In other words, when a write inhibit signal including writing (or writing action) of the head HD31 is received from the HDC60E and vibration detection information indicating that the head HD31 is subjected to vibration, the second HDC write inhibit determination unit 413E outputs the vibration detection information to the second HDC write inhibit determination unit 413F of the R / W channel 40F via the HDC60E and the transmission path WR0, and invalidates (negates or deasserts) the write enable via the second HDC write inhibit determination unit 413F, thereby inhibiting (or stopping) writing (or writing action) of the head HD31.

[0424] For example, when a write inhibit signal for writing (or writing action) of the head HD31 is received from the HDC60E, the second HDC write inhibit determination unit 413E outputs a signal for inhibiting writing (or writing action) of the head HD31 to the HDC60E, and outputs the write inhibit signal to the second HDC write inhibit determination unit 413F of the R / W channel 40F via the HDC60E and the transmission path WR0, and the write enable is invalidated (negate or deassert) via the second HDC write inhibit determination unit 413F, thereby inhibiting (or stopping) writing (or writing action) of the head HD31. In other words, when receiving a write inhibit signal including writing (or writing action) of the head HD31 and vibration detection information indicating that the head HD31 is subjected to vibration from the HDC60E, the second HDC write inhibit determination unit 413E outputs a signal to inhibit writing (or writing action) of the head HD31 to the HDC60E, outputs the vibration detection information to the second HDC write inhibit determination unit 413F of the R / W channel 40F via the HDC60E and the transmission path WR0, and invalidates (negates or deasserts) the write enable via the second HDC write inhibit determination unit 413F, thereby inhibiting (or stopping) writing (or writing action) of the head HD31.

[0425] For example, when receiving a write inhibit signal for writing (or writing action) of the head HD31 from HDC60E, the second HDC write inhibit determination unit 413E outputs the write inhibit signal to the second HDC write inhibit determination unit 413F of the R / W channel 40F via the transmission path WR1 and HDC60F, and invalidates (negates or deasserts) the write enable via the second HDC write inhibit determination unit 413F, thereby inhibiting (or stopping) the writing (or writing action) of the head HD31. In other words, when a write inhibit signal including writing (or writing action) of the head HD31 is received from the HDC60E and vibration detection information indicating that the head HD31 is subjected to vibration, the second HDC write inhibit determination unit 413E outputs the vibration detection information to the second HDC write inhibit determination unit 413F of the R / W channel 40F via the transmission path WR1 and the HDC60F, and invalidates (negates or deasserts) the write enable via the second HDC write inhibit determination unit 413F, thereby inhibiting (or stopping) writing (or writing action) of the head HD31.

[0426] For example, when receiving a write inhibit signal for writing (or writing action) of the head HD31 from HDC60E, the second HDC write inhibit determination unit 413E outputs a signal for inhibiting writing (or writing action) of the head HD31 to HDC60F, outputs the write inhibit signal to the second HDC write inhibit determination unit 413F of the R / W channel 40F via the transmission path WR1 and HDC60F, and invalidates the write enable (negate or deassert) via the second HDC write inhibit determination unit 413F, thereby inhibiting (or stopping) writing (or writing action) of the head HD31. In other words, when receiving a write inhibit signal including writing (or writing action) of the head HD31 from HDC60E and vibration detection information indicating that the head HD31 is subjected to vibration, the second HDC write inhibit determination unit 413E outputs a signal to inhibit writing (or writing action) of the head HD31 to HDC60F, outputs the vibration detection information to the second HDC write inhibit determination unit 413F of the R / W channel 40F via the transmission path WR1 and HDC60F, and invalidates (negates or deasserts) the write enable via the second HDC write inhibit determination unit 413F, thereby inhibiting (or stopping) writing (or writing action) of the head HD31.

[0427] The MPU 50E controls the actuator AC3 and MA1630 via the driver IC 20E, performing servo control for positioning the head HD30. The MPU 50E controls the writing of data to the top surface FS3 of the disk DK3 and selects the storage destination for the written data. Furthermore, the MPU 50E controls the reading of data from the top surface FS3 of the disk DK3 and controls the processing of the read data. The MPU 50E is connected to various components of the magnetic disk drive 1. For example, the MPU 50E is electrically connected to the driver IC 20E, the R / W channel 40E, and the HDC 60E.

[0428] The HDC 60E controls read / write processing based on instructions from the MPU 50E, controlling data transfer between the host 700 and the R / W channel 40E. The HDC 60E is electrically connected to, for example, the R / W channel 40E, the MPU 50E, the volatile memory 70, the buffer memory 80, and the nonvolatile memory 90. The HDC 60E is electrically connected to the R / W channel 40F via the transmission path WR0. However, the HDC 60E does not necessarily need to be connected to the R / W channel 40F via the transmission path WR0.

[0429] The HDC60E includes a servo control unit 610E and a write action determination unit 620E. The HDC60E executes the processing of each of the aforementioned units, such as the servo control unit 610E and the write action determination unit 620E, in firmware. Furthermore, the HDC60E may include each of the aforementioned units as circuits. Furthermore, a portion of the HDC60E configuration may be provided in the MPU50E. For example, the servo control unit 610E and the write action determination unit 620E may also be provided in the MPU50E. The HDC60E prohibits (or stops) the write action of the head HD30. For example, upon receiving a write prohibition signal, the HDC60E prohibits (or stops) the write action of the head HD30.

[0430] The servo control unit 610E controls the position of the head HD30. In other words, the servo control unit 610E controls access to a predetermined area of ​​the top surface FS3 of the disk DK3 by the head HD30. The servo control unit 610E includes a tracking control unit 611E and a seek control unit 612E.

[0431] The tracking control unit 611E controls the head HD30 to track a predetermined track on the top surface FS3 of the disk DK3. The tracking control unit 611E includes a DPES demodulator 6111E. Alternatively, the tracking control unit 611E may include an SPES demodulator.

[0432] The DPES demodulation unit 6111E reads the data sector DS on the top surface FS3 of the disk DK3 and demodulates the DPES.

[0433] The seek control unit 612E controls the head HD30 to seek from a predetermined track to a target track on the top surface FS3 of the disk DK3.

[0434] The write operation determination unit 620E is connected to the R / W channel 40F via the wiring WR0. Alternatively, the write operation determination unit 620E may not be connected to the R / W channel 40F via the wiring WR0. The write operation determination unit 620E includes a position write operation determination unit 621E and a speed write operation determination unit 622E. The position write operation determination unit 621E determines the write operation of the head HD30 based on the position of the head HD30. The speed write operation determination unit 622E determines the write operation of the head HD30 based on the speed of the head HD30.

[0435] The write operation determination unit 620E determines whether or not to prohibit (or stop) writing (or the write operation) of the head HD30 corresponding to the HDC 60E.

[0436] When receiving a write prohibition determination signal (or write prohibition determination information) for writing (or writing action) of the head HD30 corresponding to HDC60E, the write action determination unit 620E determines whether to prohibit (or stop) writing (or writing action) of the head HD30 based on the SPES demodulated by reading from the servo sector SS of the disk DK3 through the head HD30 or the DPES demodulated by reading from the data sector DS.

[0437] Upon receiving a write inhibit determination signal (or write inhibit determination information) for writing (or writing operation) of the head HD30 corresponding to the HDC 60E, the write operation determination unit 620E determines whether the SPES or DPES corresponding to the head HD30 exceeds a threshold value.

[0438] When determining that the SPES or DPES corresponding to head HD30 exceeds the threshold, the write operation determination unit 620E determines to prohibit (or stop) writing (or writing operation) of head HD30 and outputs a write prohibition signal to the R / W channel 40E corresponding to HDC60E.

[0439] When receiving a signal from the second HDC write inhibit determination unit 413E to inhibit writing (or a write operation) to the head HD31 corresponding to the HDC 60F, the write operation determination unit 620E may output a write inhibit signal to the R / W channel 40F. When receiving a signal from the second HDC write inhibit determination unit 413E to inhibit writing (or a write operation) to the head HD31 corresponding to the HDC 60F, the write operation determination unit 620E may output a write inhibit signal to the R / W channel 40F via the transmission path WR0.

[0440] In addition, when receiving a signal from the second HDC write prohibition determination unit 413E to prohibit writing (or writing action) of the head HD31 corresponding to HDC60F, the write action determination unit 620E may also not output a write prohibition signal to the R / W channel 40F based on the status of the system controller 130F, the head HD31, etc.

[0441] For example, when determining that the SPES or DPES corresponding to the head HD30 exceeds the threshold, the write operation determination unit 620E may output a write inhibit signal to the R / W channel 40F.

[0442] For example, when the SPES or DPES corresponding to the head HD30 is determined to be below the threshold, the write operation determination unit 620E prohibits (or stops) writing (or writing operation) by the head HD30 without passing through the HDC 60E. In other words, when the SPES or DPES corresponding to the head HD30 is determined to be below the threshold, the write operation determination unit 620E continues (or continues) writing (or writing operation) by the head HD30.

[0443] The system controller 130F includes an R / W channel 40F, an MPU 50F, and an HDC 60F. The system controller 130F is electrically connected to the driver IC 20F, the head amplifier IC 30F, the write disable detector 180, the controller communication unit 190, and the host system 700. The system controller 130F is electrically connected to the system controller 130E via transmission paths WR0 and WR1. The system controller 130F may also include an SPM control unit 210F, a VCM control unit 220F, and an MA control unit 230F. The system controller 130F may also include the driver IC 20F and the head amplifier IC 30F.

[0444] The R / W channel 40F performs signal processing for read data transmitted from the lower surface RS3 of the disk DK3 to the host computer 700, and for write data transmitted from the host computer 700, based on instructions from the MPU 50F. The R / W channel 40F is electrically connected to, for example, the head amplifier IC 30F, the MPU 50F, the HDC 60F, and the write inhibit detector 180. The R / W channel 40F is electrically connected to the write operation determination unit 620E (HDC 60E) via the transmission path WR0. Alternatively, the R / W channel 40F may not be connected to the write operation determination unit 620E (HDC 60E) via the transmission path WR0. The R / W channel 40F includes a write inhibit unit 410F.

[0445] The write inhibit unit 410F inhibits (or stops) writing (or writing operations) by the heads HD30 and HD31 via the HDCs 60E and 60F. The write inhibit unit 410F is connected to the write operation determination unit 620E (HDC 60E) via the transmission path WR0. Alternatively, the write inhibit unit 410F may not be connected to the write operation determination unit 620E (HDC 60E) via the transmission path WR0. The write inhibit unit 410F includes a vibration sensor write inhibit determination unit 411F, a first HDC write inhibit determination unit 412F, and a second HDC write inhibit determination unit 413F.

[0446] When vibration or shock is detected by the vibration sensor 170 , the vibration sensor write inhibition determination unit 411F determines whether to determine inhibition (or stop) of writing (or writing operation) by the head HD31 or not.

[0447] For example, upon receiving a write inhibit determination execution signal, the vibration sensor write inhibit determination unit 411F determines whether the vibration or shock is greater than a predetermined value via the head HD31 based on the write inhibit determination execution signal. For example, if it is determined that the vibration or shock is greater than the predetermined value, the vibration sensor write inhibit determination unit 411F determines to inhibit (or stop) writing (or a write operation) to the head HD31. For example, if it is determined that the vibration or shock is greater than the predetermined value, the vibration sensor write inhibit determination unit 411F outputs a write inhibit determination signal to determine that writing (or a write operation) to the head HD31 is prohibited (or stopped). For example, if it is determined that the vibration or shock is below the predetermined value, the vibration sensor write inhibit determination unit 411F does not determine to inhibit (or stop) writing (or a write operation) to the head HD31.

[0448] The first HDC write inhibit determination unit 412F inhibits (or stops) writing (or writing operation) to the head HD30 corresponding to the HDC 60E. For example, upon receiving a write inhibit signal from the HDC 60F to inhibit (or stop) writing (or writing operation) to the head HD30, the first HDC write inhibit determination unit 412F outputs the write inhibit signal to the first HDC write inhibit determination unit 412E of the R / W channel 40E via the HDC 60F and the transmission path WR1. The write strobe is negated (negate or deassert) via the first HDC write inhibit determination unit 412E, thereby inhibiting (or stopping) writing (or writing operation) to the head HD30. In other words, when receiving a write inhibit signal including a signal for inhibiting (or stopping) writing (or writing action) of the head HD30 from the HDC60F and vibration detection information indicating that the head HD30 is subjected to vibration, the first HDC write inhibit determination unit 412F outputs the vibration detection information to the first HDC write inhibit determination unit 412E of the R / W channel 40E via the HDC60F and the transmission path WR1, and invalidates (negates or deasserts) the write enable via the first HDC write inhibit determination unit 412E, thereby inhibiting (or stopping) writing (or writing action) of the head HD30.

[0449] For example, when receiving a write inhibit signal for writing (or writing action) of the head HD30 from the HDC60F, the first HDC write inhibit determination unit 412F outputs a signal for inhibiting writing (or writing action) of the head HD30 to the HDC60F, outputs the write inhibit signal to the first HDC write inhibit determination unit 412E of the R / W channel 40E via the HDC60F and the transmission path WR1, and invalidates the write enable (negate or deassert) via the first HDC write inhibit determination unit 412E, thereby inhibiting (or stopping) writing (or writing action) of the head HD30. In other words, when receiving a write inhibit signal including writing (or writing action) of the head HD30 from the HDC60F and vibration detection information indicating that the head HD30 is subjected to vibration, the first HDC write inhibit determination unit 412F outputs a signal to inhibit writing (or writing action) of the head HD30 to the HDC60F, outputs the vibration detection information to the first HDC write inhibit determination unit 412E of the R / W channel 40E via the HDC60F and the transmission path WR1, and invalidates (negates or deasserts) the write enable via the first HDC write inhibit determination unit 412E, thereby inhibiting (or stopping) writing (or writing action) of the head HD30.

[0450] For example, when receiving a write inhibit signal for writing (or writing action) of the head HD30 from the HDC60F, the first HDC write inhibit determination unit 412F outputs the write inhibit signal to the first HDC write inhibit determination unit 412E of the R / W channel 40E via the transmission path WR0 and HDC60E, and invalidates (negates or deasserts) the write enable via the first HDC write inhibit determination unit 412E, thereby inhibiting (or stopping) the writing (or writing action) of the head HD30. In other words, when receiving a write inhibit signal including writing (or writing action) of the head HD30 from the HDC60F and vibration detection information indicating that the head HD30 is subjected to vibration, the first HDC write inhibit determination unit 412F outputs the vibration detection information to the first HDC write inhibit determination unit 412E of the R / W channel 40E via the transmission path WR0 and HDC60E, and invalidates (negates or deasserts) the write enable via the first HDC write inhibit determination unit 412E, thereby inhibiting (or stopping) writing (or writing action) of the head HD30.

[0451] For example, when receiving a write inhibit signal for writing (or writing action) of the head HD30 from HDC60F, the first HDC write inhibit determination unit 412F outputs a signal for inhibiting writing (or writing action) of the head HD30 to HDC60E, and outputs the write inhibit signal to the first HDC write inhibit determination unit 412E of the R / W channel 40E via the transmission path WR0 and HDC60E, and invalidates the write enable (negate or deassert) via the first HDC write inhibit determination unit 412E, thereby inhibiting (or stopping) writing (or writing action) of the head HD30. In other words, when receiving a write inhibit signal including writing (or writing action) of the head HD30 from HDC60F and vibration detection information indicating that the head HD30 is subjected to vibration, the first HDC write inhibit determination unit 412F outputs a signal to inhibit writing (or writing action) of the head HD30 to HDC60E, outputs the vibration detection information to the first HDC write inhibit determination unit 412E of the R / W channel 40E via the transmission path WR0 and HDC60E, and invalidates (negates or deasserts) the write enable via the first HDC write inhibit determination unit 412E, thereby inhibiting (or stopping) writing (or writing action) of the head HD30.

[0452] The second HDC write inhibit determination unit 413F inhibits (or stops) writing (or the writing operation) of the head HD31 corresponding to the HDC 60F. For example, upon receiving a write inhibit signal from the HDC 60F regarding writing (or the writing operation) of the head HD31, the second HDC write inhibit determination unit 413F negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or the writing operation) of the head HD31. In other words, upon receiving a write inhibit signal from the HDC 60F regarding writing (or the writing operation) of the head HD31 and vibration detection information indicating that the head HD31 is vibrating, the second HDC write inhibit determination unit 413F negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or the writing operation) of the head HD31.

[0453] For example, upon receiving a write inhibit signal for writing (or a write operation) by head HD30 corresponding to HDC60E, the second HDC write inhibit determination unit 413F negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or a write operation) by head HD31. In other words, upon receiving vibration detection information including a write inhibit signal for writing (or a write operation) by head HD30 corresponding to HDC60E and indicating that head HD30 is vibrating, the second HDC write inhibit determination unit 413F negates (negates or deasserts) the write strobe, thereby inhibiting (or stopping) writing (or a write operation) by head HD31.

[0454] The MPU 50F controls the actuator AC3 and MA1631 via the driver IC 20F, performing servo control for positioning the head HD31. The MPU 50F controls the writing of data to the lower surface RS3 of the disk DK3 and selects the storage destination for the written data. Furthermore, the MPU 50F controls the reading of data from the lower surface RS3 of the disk DK3 and controls the processing of the read data. The MPU 50F is connected to various components of the magnetic disk drive 1. For example, the MPU 50F is electrically connected to the driver IC 20F, the R / W channel 40F, and the HDC 60F.

[0455] The HDC 60F controls read / write processing based on instructions from the MPU 50F, controlling data transfer between the host 700 and the R / W channel 40F. The HDC 60F is electrically connected to, for example, the R / W channel 40F and the MPU 50F. The HDC 60F is electrically connected to the R / W channel 40E via the transmission path WR1. However, the HDC 60F does not necessarily need to be connected to the R / W channel 40E via the transmission path WR1.

[0456] The HDC60F includes a servo control unit 610F and a write operation determination unit 620F. The HDC60F executes the processing of each of the aforementioned units, such as the servo control unit 610F and the write operation determination unit 620F, in firmware. Furthermore, the HDC60F may include each of the aforementioned units as circuits. Furthermore, a portion of the HDC60F configuration may be provided in the MPU50F. For example, the servo control unit 610F and the write operation determination unit 620F may also be provided in the MPU50F. The HDC60F prohibits (or stops) the write operation of the head HD31. For example, upon receiving a write prohibition signal, the HDC60F prohibits (or stops) the write operation of the head HD31.

[0457] The servo control unit 610F controls the position of the head HD31. In other words, the servo control unit 610F controls access to a predetermined area of ​​the lower surface RS3 of the disk DK3 by the head HD31. The servo control unit 610F includes a tracking control unit 611F and a seek control unit 612F.

[0458] The tracking control unit 611F controls the head HD31 to track a predetermined track on the lower surface RS3 of the disk DK3. The tracking control unit 611F includes a DPES demodulator 6111F. Alternatively, the tracking control unit 611F may include an SPES demodulator.

[0459] The DPES demodulation unit 6111F reads the data sector DS on the lower surface RS3 of the disk DK3 and demodulates the DPES.

[0460] The seek control unit 612F controls the head HD31 to seek from a predetermined track to a target track on the lower surface RS3 of the disk DK3.

[0461] The write operation determination unit 620F is connected to the R / W channel 40E via the wiring WR1. Alternatively, the write operation determination unit 620F may not be connected to the R / W channel 40E via the wiring WR1. The write operation determination unit 620F includes a position write operation determination unit 621F and a speed write operation determination unit 622F. The position write operation determination unit 621F determines the write operation of the head HD31 based on the position of the head HD31. The speed write operation determination unit 622F determines the write operation of the head HD31 based on the speed of the head HD31.

[0462] The write operation determination unit 620F determines whether or not to prohibit (or stop) writing (or the write operation) of the head HD31 corresponding to the HDC 60F.

[0463] When receiving a write prohibition determination signal (or write prohibition determination information) for writing (or writing action) by the head HD31 corresponding to HDC60F, the write action determination unit 620F determines whether to prohibit (or stop) writing (or writing action) by the head HD31 based on the SPES demodulated by reading from the servo sector SS of the disk DK3 through the head HD31 or the DPES demodulated by reading from the data sector DS.

[0464] Upon receiving a write inhibit determination signal (or write inhibit determination information) for writing (or writing operation) of the head HD31 corresponding to the HDC 60F, the write operation determination unit 620F determines whether the SPES or DPES corresponding to the head HD31 exceeds a threshold value.

[0465] When it is determined that the SPES or DPES corresponding to the head HD31 exceeds the threshold, the write operation determination unit 620F determines to prohibit (or stop) the writing (or writing operation) of the head HD31 and outputs a write prohibition signal to the R / W channel 40F corresponding to the HDC60F.

[0466] When receiving a signal from the first HDC write inhibit determination unit 412F to inhibit writing (or a write operation) to the head HD30 corresponding to the HDC 60E, the write operation determination unit 620F may output a write inhibit signal to the R / W channel 40E. When receiving a signal from the first HDC write inhibit determination unit 412F to inhibit writing (or a write operation) to the head HD30 corresponding to the HDC 60E, the write operation determination unit 620F may output a write inhibit signal to the R / W channel 40E via the transmission path WR1.

[0467] In addition, when receiving a signal from the first HDC write prohibition determination unit 412F to prohibit writing (or writing action) of the head HD30 corresponding to the HDC60E, the write action determination unit 620F may not output a write prohibition signal to the R / W channel 40E according to the status of the system controller 130E, the head HD30, etc.

[0468] For example, when determining that the SPES or DPES corresponding to the head HD31 exceeds the threshold, the write operation determination unit 620F may output a write inhibit signal to the R / W channel 40E.

[0469] For example, when the SPES or DPES corresponding to the head HD31 is determined to be below the threshold, the write operation determination unit 620F prohibits (or stops) writing (or writing operation) by the head HD31 without passing through the HDC 60F. In other words, when the SPES or DPES corresponding to the head HD31 is determined to be below the threshold, the write operation determination unit 620F continues (or continues) writing (or writing operation) by the head HD31.

[0470] Figure 23 This is a schematic diagram showing an example of a demodulation method of SPES and DPES according to the third embodiment. Figure 23 , read heads RH30 and RH31 are shown positioned within a servo sector SV of a predetermined area of ​​the disk DK3. Figure 23 In the example shown, the read head RH is positioned at the reference position RP0.

[0471] The system controller 130 demodulates the SPES by reading the servo sector SV using the read heads RH30 and RH31. Since the read heads RH30 and RH31 are offset in the circumferential direction at intervals along the track, the system controller 130 can demodulate the SPES at different timings.

[0472] In addition, the system controller 130 demodulates the DPES by reading the data sector DS using the read heads RH30 and RH31. Since the read heads RH30 and RH31 are offset in the circumferential direction at intervals along the track, the system controller 130 can demodulate the DPES at different timings.

[0473] Figure 24 Schematic diagram showing an example of servo gating according to the third embodiment. Figure 24 In the example, the horizontal axis represents time. Figure 24 In the time on the horizontal axis, time passes as one moves toward the front end of the arrow. Figure 24 The time on the horizontal axis of FIG indicates timings t240 and t241. Figure 24 In the time on the horizontal axis, timing t241 corresponds to the time after timing t240. Figure 24Servo gates SG1 and SG2 are shown in FIG. Servo gate SG1 corresponds to timing t240. Servo gate SG2 corresponds to timing t241. Servo gate SG1 corresponds to the timing when read head RH30 reads the servo sector SV and demodulates the SPES, while servo gate SG2 corresponds to the timing when read head RH31 reads the servo sector SV and demodulates the DPES. Servo gates SG1 and SG2 are enabled when they rise and disabled when they fall.

[0474] At timing t240, the system controller 130 activates the servo gate SG1, and the read head RH30 reads the servo sector SV and demodulates the SPES. At timing t241, the system controller 130 activates the servo gate SG2, and the read head RH31 reads the servo sector SV and demodulates the SPES.

[0475] Furthermore, the system controller 130 activates the servo gate SG1 at timing t240, and the read head RH30 reads the data sector DS and demodulates the DPES. The system controller 130 activates the servo gate SG2 at timing t241, and the read head RH31 reads the data sector DS and demodulates the DPES.

[0476] Figure 25 This is a flowchart showing an example of a method for stopping a write operation according to the third embodiment.

[0477] The system controller 130 reads a data sector using a predetermined read head RH among the plurality of read heads RH (B2501), demodulates and obtains a DPES based on predetermined information (or predetermined data) in the data sector (B1402). The system controller 130 then determines whether the current position error corresponding to the predetermined read head HD is greater than a threshold for stopping the predetermined read head HD (B1403).

[0478] If the system controller 130 determines that the current position error corresponding to the designated head HD is below the threshold (B1403: No), the system controller 130 determines whether the next position error of the designated head HD is greater than the threshold for stopping the head HD (B1404). If the next position error is determined to be below the threshold (B1404: No), the system controller 130 proceeds to the process of B1401. If the next position error is determined to be greater than the threshold (B1404: Yes), the system controller 130 proceeds to the process of B1705.

[0479] When it is determined that the current position error corresponding to the predetermined head HD is greater than the threshold value (B1403: Yes), the system controller 130 stops (prohibits) the writing action of the predetermined head HD (B1705), and also stops (prohibits) the writing action of other heads HD different from the predetermined head HD (B1706), and ends the processing.

[0480] According to the third embodiment, a magnetic disk drive 1 includes multiple disks DK, multiple heads HD, and multiple system controllers 130 corresponding to the multiple heads HD. Each of the multiple heads HD includes a write head WH and multiple read heads RH. A predetermined system controller 130 among the multiple system controllers 130 uses a predetermined read head RH among the multiple read heads RH of the predetermined head HD corresponding to the predetermined system controller 130 to read a servo sector SV of the disk DK corresponding to the predetermined read head RH and demodulate the SPES. A predetermined system controller 130 among the multiple system controllers 130 uses a predetermined read head RH among the multiple read heads RH of the predetermined head HD corresponding to the predetermined system controller 130 to read a data sector DS of the disk DK corresponding to the predetermined read head RH and demodulate the DPES. The predetermined system controller 130 calculates the current position error of the predetermined head HD based on the SPES or DPES. If the current position error of the predetermined head HD exceeds a threshold for stopping (or inhibiting) the write operation of the predetermined head HD, the predetermined system controller 130 stops (or inhibits) the write operation of the predetermined head HD. When the write operation by a predetermined head HD is stopped (or prohibited), the predetermined system controller 130 can also stop (or prohibit) the write operation by other heads HD corresponding to other heads HD different from the predetermined head HD among the plurality of system controllers 130. Therefore, the magnetic disk device 1 can improve formatting efficiency.

[0481] (Variation 3)

[0482] The configuration of the magnetic disk device 1 according to the third modification of the third embodiment is different from the configuration of the magnetic disk device 1 according to the third embodiment.

[0483] Figure 26 This is a schematic diagram showing an example of the configuration of the magnetic disk device 1 according to Modification 3.

[0484] exist Figure 26 In the illustrated example, the write inhibit section 410E includes a vibration sensor write inhibit determination section 411E and a first HDC write inhibit determination section 412E.

[0485] The write operation determination unit 620E further includes a PES write operation determination unit 623E. The PES write operation determination unit 623E determines whether to prohibit (or stop) the write operation of the head HD31 (write head WH31) based on the SPES or DPES demodulated by the head HD31 (read head RH310 or RH311) corresponding to the HDC 60F when the servo sector SV or data sector DS of the lower surface RS3 of the disk DK3 is read via the HDC 60F.

[0486] For example, upon receiving a write-inhibit signal that prohibits (or stops) writing (or a write operation) by head HD30, the PES write operation determination unit 623E outputs a write-inhibit signal that prohibits (or stops) writing (or a write operation) by head HD31 (write head WH31) to the R / W channel 40F via the write-inhibit information transmission unit 1911 and the HDC 60F. In other words, upon receiving vibration detection information that includes a write-inhibit signal that prohibits (or stops) writing (or a write operation) by head HD30 and indicates that head HD30 is vibrating, the PES write operation determination unit 623E outputs vibration detection information that prohibits (or stops) writing (or a write operation) by head HD31 (write head WH31) to the R / W channel 40F via the write-inhibit information transmission unit 1911 and the HDC 60F.

[0487] Furthermore, upon receiving a write-inhibit signal for inhibiting (or stopping) writing (or a writing operation) by the head HD30, the PES write operation determination unit 623E may not output the write-inhibit signal for inhibiting (or stopping) writing (or a writing operation) by the head HD31 (write head WH31) to the R / W channel 40F, depending on the status of the system controller 130F or the head HD31. In other words, upon receiving vibration detection information including a write-inhibit signal for inhibiting (or stopping) writing (or a writing operation) by the head HD30 and indicating that the head HD30 is vibrating, the PES write operation determination unit 623E may not output vibration detection information for inhibiting (or stopping) writing (or a writing operation) by the head HD31 (write head WH31) to the R / W channel 40F, depending on the status of the system controller 130F or the head HD31.

[0488] The write inhibit section 410F includes a vibration sensor write inhibit determination section 411F and a second HDC write inhibit determination section 413F.

[0489] The write operation determination unit 620F further includes a PES write operation determination unit 623F. The PES write operation determination unit 623F determines whether to prohibit (or stop) writing (or the write operation) by the head HD30 (write head WH30) based on the SPES or DPES demodulated by the head HD30 (read heads RH300 and RH301) corresponding to the HDC 60E when reading the servo sector SV or the data sector DS on the upper surface FS3 of the disk DK3 via the HDC 60E.

[0490] For example, upon receiving a write-inhibit signal that prohibits (or stops) writing (or a write operation) by head HD31, the PES write operation determination unit 623F outputs the write-inhibit signal that prohibits (or stops) writing (or a write operation) by head HD30 (write head WH30) to the R / W channel 40E via the write-inhibit information transmission unit 1911 and the HDC 60E. In other words, upon receiving vibration detection information that includes a write-inhibit signal that prohibits (or stops) writing (or a write operation) by head HD31 and indicates that head HD31 is vibrating, the PES write operation determination unit 623F outputs vibration detection information that prohibits (or stops) writing (or a write operation) by head HD30 (write head WH30) to the R / W channel 40E via the write-inhibit information transmission unit 1911 and the HDC 60E.

[0491] Furthermore, upon receiving a write-inhibit signal for inhibiting (or stopping) writing (or a write operation) by the head HD31, the PES write operation determination unit 623F may not output the write-inhibit signal for inhibiting (or stopping) writing (or a write operation) by the head HD30 (write head WH30) to the R / W channel 40E, depending on the status of the system controller 130E or the head HD30. In other words, upon receiving vibration detection information including a write-inhibit signal for inhibiting (or stopping) writing (or a write operation) by the head HD31 and indicating that the head HD31 is vibrating, the PES write operation determination unit 623F may not output vibration detection information for inhibiting (or stopping) writing (or a write operation) by the head HD30 (write head WH30) to the R / W channel 40E, depending on the status of the system controller 130E or the head HD30.

[0492] According to variation 3, the magnetic disk drive 1 further includes a write-inhibit information transmission unit 1911. When the current position error of a predetermined head HD exceeds a threshold for stopping (or inhibiting) the write operation of the predetermined head HD, the predetermined system controller 130 stops (or inhibits) the write operation by the predetermined head HD. When stopping (or inhibiting) the write operation by the predetermined head HD, the predetermined system controller 130 can also stop (or inhibit) the write operation by other heads HD corresponding to other system controllers 130 among the plurality of system controllers 130. For example, the predetermined system controller 130 stops (or inhibits) the write operation by the other heads HD by outputting a write-inhibit signal to the other system controllers 130 via the write-inhibit information transmission unit 1911. Therefore, the magnetic disk drive 1 can improve formatting efficiency.

[0493] (Fourth embodiment)

[0494] The configuration of the magnetic disk device 1 according to the fourth embodiment is different from the configurations of the magnetic disk devices 1 according to the aforementioned embodiment and the aforementioned modified examples.

[0495] Figure 27 It is a schematic diagram showing an example of the configuration of the magnetic disk device 1 according to the fourth embodiment.

[0496] exist Figure 27 In the example shown, disk DK includes disk DK4. Disk DK4 is mounted on spindle 12. Disk DK4 includes an upper surface FS4 and a lower surface RS4 opposite to upper surface FS4. Disk DK4 may include two or more disks.

[0497] The head HD includes heads HD4 and HD5. Head HD4 includes a head HD40 facing the upper surface FS4 of disk DK4 and a head HD41 facing the lower surface RS4 of disk DK4. Furthermore, head HD4 may include only one head or three or more heads. Head HD4 includes a write head WH4 for writing data to disk DK4 and a read head RH4 for reading data written to disk DK4. The write head WH4 includes a write head WH40 and a write head WH41. The read head RH4 includes a read head RH40 and a read head RH41.

[0498] The head HD40 includes a write head WH40 for writing data to the upper surface FS4 and a read head RH40 for reading data written to the upper surface FS4. The head HD41 includes a write head WH41 for writing data to the lower surface RS4 and a read head RH41 for reading data written to the lower surface RS4.

[0499] The head HD5 includes a head HD50 facing the upper surface FS4 of the disk DK4 and a head HD51 facing the lower surface RS4 of the disk DK4. The head HD5 may have only one head or three or more heads. The head HD5 includes a write head WH5 for writing data to the disk DK4 and a read head RH5 for reading data written to the disk DK4. The write head WH5 includes a write head WH50 and a write head WH51. The read head RH5 includes a read head RH50 and a read head RH51.

[0500] The head HD50 includes a write head WH50 for writing data to the upper surface FS4 and a read head RH50 for reading data written to the upper surface FS4. The head HD51 includes a write head WH51 for writing data to the lower surface RS4 and a read head RH51 for reading data written to the lower surface RS4.

[0501] Actuator block BK includes actuator blocks BK4 and BK5. Actuator block BK4 is rotatably mounted on bearing BR3, which is vertically mounted on bottom wall HSB. Actuator block BK5 is rotatably mounted on bearing BR4, which is also vertically mounted on bottom wall HSB. Bearing BR4 is located on the opposite side of bearing BR3 relative to a line passing through the center of spindle 12 in a top view. For example, bearing BR3 and bearing BR4 are located symmetrically relative to a line passing through the center of spindle 12 in a top view.

[0502] The arm AM includes arms AM4 and AM5. The arm AM4 includes an arm AM40 located on the upper surface FS4 side of the disk DK4 and an arm AM41 located on the lower surface RS4 side of the disk DK4. Depending on the number of heads HD4, the arm AM4 may include only one arm or three or more arms. The arm AM4 is connected to the actuator block BK4.

[0503] The arm AM5 includes an arm AM50 located on the upper surface FS4 side of the disk DK4 and an arm AM51 located on the lower surface RS4 side of the disk DK4. The arm AM5 may include only one arm or three or more arms, depending on the number of heads HD5. The arm AM5 is connected to the actuator block BK5.

[0504] The VCM 14 includes VCMs 144 and 145. The VCM 144 is connected to the actuator block BK4 on the side opposite to the arm AM4. The VCM 145 is connected to the actuator block BK5 on the side opposite to the arm AM5.

[0505] The suspension 15 includes suspensions 154 and 155. The suspension 154 is mounted on the arm AM4. The suspension 154 is equipped with a head HD4 at the top end portion on the side opposite to the end portion connected to the arm AM4. The suspension 154 includes a suspension 1540 mounted on the arm AM40 and a suspension 1541 mounted on the arm AM41. In addition, the suspension 154 may have only one suspension or three or more suspensions depending on the number of arms AM4. The suspension 1540 is equipped with a head HD40 at the top end portion on the side opposite to the end portion connected to the arm AM40. The suspension 1541 is equipped with a head HD41 at the top end portion on the side opposite to the end portion connected to the arm AM41.

[0506] Suspension 155 is mounted on arm AM5. Suspension 155 has head HD5 mounted on its top end opposite to the end connected to arm AM5. Suspension 155 includes suspension 1550 mounted on arm AM50 and suspension 1551 mounted on arm AM51. Suspension 155 may have only one suspension or three or more suspensions, depending on the number of arms AM5. Suspension 1550 has head HD50 mounted on its top end opposite to the end connected to arm AM50. Suspension 1551 has head HD51 mounted on its top end opposite to the end connected to arm AM51.

[0507] The MA 164 includes MAs 164 and 165. The MA 164 is mounted on the suspension 154. The MA 164 finely controls the radial motion of the head HD4. For example, compared to the radial motion control of the head HD4 by the VCM 144, the MA 164 provides more precise control of the radial motion of the head HD4. For example, the MA 164 includes an MA 1640 mounted on the suspension 1540 and an MA 1641 mounted on the suspension 1541. Depending on the number of suspensions 154, the MA 164 can include either a single MA or three or more.

[0508] The MA1640 finely controls the radial motion of the head HD40. For example, compared to the VCM144's control of the head HD40's radial motion, the MA1640 controls the head HD40's radial motion more finely. The MA1641 finely controls the head HD41's radial motion. For example, compared to the VCM144's control of the head HD41's radial motion, the MA1641 controls the head HD41's radial motion more finely. Furthermore, the MA1640 and MA1641 can each be driven independently of the VCM144.

[0509] The MA 165 is mounted on the suspension 155. The MA 165 finely controls the radial motion of the head HD5. For example, compared to the VCM 145's control of the radial motion of the head HD5, the MA 165 provides more precise control of the radial motion of the head HD5. For example, the MA 165 includes an MA 1650 mounted on the suspension 1550 and an MA 1651 mounted on the suspension 1551. Depending on the number of suspensions 155, the MA 165 can have either a single MA or three or more MAs.

[0510] MA1650 finely controls the radial motion of head HD50. For example, compared to the VCM145's control of head HD50's radial motion, MA1650 controls head HD50's radial motion more finely. MA1651 finely controls head HD51's radial motion. For example, compared to the VCM145's control of head HD51's radial motion, MA1651 controls head HD51's radial motion more finely. Furthermore, MA1650 and MA1651 can be driven independently of VCM145.

[0511] Actuator AC includes actuators AC4 and AC5. Actuator AC4 is rotatably mounted on bearing BR3. Actuator AC4 is comprised of suspension 154, MA164, arm AM4, actuator block BK4, and VCM144. Actuator AC4 drives VCM144 around the rotation axis of bearing BR3 and precisely drives MA164, thereby positioning head HD4 mounted on suspension 154 at a predetermined position on disk DK4. If MA164 is not present, actuator AC4 drives VCM144 around bearing BR3, thereby positioning head HD4 mounted on suspension 154 at a predetermined position on disk DK4.

[0512] The actuator AC5 is rotatably mounted on the bearing BR4. The actuator AC5 consists of the suspension 155, the MA165, the arm AM5, the actuator block BK5, and the VCM145. The actuator AC5 drives the VCM145 about the rotation axis of the bearing BR4 and precisely drives the MA165, thereby positioning the head HD5 mounted on the suspension 155 at a predetermined position on the disk DK4. If the MA165 is not present, the actuator AC5 drives the VCM145 about the bearing BR4, thereby positioning the head HD5 mounted on the suspension 155 at a predetermined position on the disk DK4.

[0513] The driver IC 20 includes a driver IC 20G and a driver IC 20H. Driver ICs 20G and 20H are formed in separate configurations, such as separate circuits. Alternatively, driver ICs 20G and 20H may be formed in an integrated configuration, such as an integrated circuit. The SPM control unit 210 includes an SPM control unit 210G. The VCM control unit 220 includes VCM control units 220G and 220H. The MA control unit 230 includes MA control units 230G and 230H.

[0514] The driver IC 20G controls the driving of the SPM 13, VCM 144, and MA 164 under the control of the system controller 130G (specifically, the MPU 50G or HDC 60G described later). The driver IC 20G is electrically connected to the SPM 13, driver IC 20D, VCM 144, and MA 164. The driver IC 20G is connected to the SPM 13, driver IC 20G, VCM 144, and MA 164, for example, via a predetermined interface.

[0515] The driver IC 20G includes an SPM control unit 210G, a VCM control unit 220G, and a microactuator (MA) control unit 230G. The SPM control unit 210G controls the rotation of the SPM 13. The VCM control unit 220G controls the drive of the VCM 144 by controlling the current (or voltage) supplied to the VCM 144. The MA control unit 230G controls the drive of the MA 164 by controlling the current (or voltage) supplied to the MA 164. Furthermore, a portion of the components of the driver IC 20G (e.g., the SPM control unit 210G, the VCM control unit 220G, and the MA control unit 230G) may be provided in the system controller 130G. If the actuator AC4 does not include the MA 164, the MA control unit 230G may also be omitted.

[0516] The driver IC 20H controls the driving of the VCM 145 and the MA 165 under the control of the system controller 130H (specifically, the MPU 50H or the HDC 60H described later). The driver IC 20H is electrically connected to the VCM 145 and the MA 165. The driver IC 20H is connected to the VCM 145 and the MA 165 through, for example, a predetermined interface.

[0517] The driver IC 20H includes a VCM control unit 220H and an MA control unit 230H. The VCM control unit 220H controls the current (or voltage) supplied to the VCM 145 to control the driving of the VCM 145. The MA control unit 230H controls the current (or voltage) supplied to the MA 165 to control the driving of the MA 165. Alternatively, a portion of the driver IC 20H (e.g., the VCM control unit 220H and the MA control unit 230H) may be provided in the system controller 130H. If the actuator AC5 does not include the MA 165, the MA control unit 230H may also be omitted.

[0518] The head amplifier IC30 includes a head amplifier IC30G and a head amplifier IC30H. The head amplifier IC30 may include only one head amplifier IC or more than three head amplifier ICs. The head amplifier ICs 30G and 30H are formed in separate configurations, such as separate circuits. Alternatively, the head amplifier ICs 30G and 30H may be formed in an integrated configuration, such as an integrated circuit. The read head selection unit 310 includes read head selection units 310G and 310H. Alternatively, the read head selection unit 310 may include only one read head selection unit or more than three read head selection units. The read signal detection unit 320 includes read signal detection units 320G and 320H. Alternatively, the read signal detection unit 320 may include only one read signal detection unit or more than three read signal detection units.

[0519] The head amplifier IC 30G amplifies the read signal received from the disk DK4 and outputs it to the system controller 130G (specifically, the read / write (R / W) channel 40G described later). The head amplifier IC 30G is electrically connected to each head HD4, for example, heads HD40 and HD41. Furthermore, the head amplifier IC 30G outputs a write current to the head HD4 in accordance with the signal output from the R / W channel 40G.

[0520] The head amplifier IC 30G includes a head selector 310G and a read signal detector 320G. The head selector 310G selects the read head RH4 in the actuator AC4 to read data from the disk DK4. The read signal detector 320G detects the signal (read signal) read by the read head RH4 from the disk DK4. Alternatively, a portion of the components of the head amplifier IC 30G (e.g., the head selector 310G and the read signal detector 320G) may be provided in the system controller 130G.

[0521] The head amplifier IC30H amplifies the read signal received from the disk DK4 and outputs it to the system controller 130H (specifically, the read / write (R / W) channel 40B described later). The head amplifier IC30H is electrically connected to each head HD5, for example, heads HD50 and HD51. Furthermore, the head amplifier IC30H outputs a write current to the head HD5 in accordance with the signal output from the R / W channel 40H.

[0522] The head amplifier IC 30H includes a head selector 310H and a read signal detector 320H. The head selector 310H selects the read head RH5 in the actuator AC5, which reads data from the disk DK4. The read signal detector 320H selects the read head RH4, which reads data from the disk DK4. The read signal detector 320H detects the signal (read signal) read by the read head RH4 from the disk DK4. Alternatively, a portion of the components of the head amplifier IC 30H (e.g., the head selector 310H and the read signal detector 320H) may be provided in the system controller 130H.

[0523] The system controller 130 includes system controllers 130G and 130H. The system controller 130 may include only one system controller or three or more system controllers. The system controllers 130G and 130H may be implemented as separate components, such as separate circuits. Alternatively, the system controllers 130G and 130H may be implemented as an integrated component, such as an integrated circuit.

[0524] The R / W channel 40 includes R / W channels 40G and 40H. Furthermore, the R / W channel 40 may have only one R / W channel or may have three or more R / W channels. The vibration sensor write inhibit determination unit 411 includes vibration sensor write inhibit determination units 411G and 411H. Furthermore, the vibration sensor write inhibit determination unit 411 may have only one vibration sensor write inhibit determination unit or may have three or more vibration sensor write inhibit determination units. The first HDC write inhibit determination unit 412 includes first HDC write inhibit determination units 412G and 412H. Furthermore, the first HDC write inhibit determination unit 412 may have only one first HDC write inhibit determination unit or may have three or more first HDC write inhibit determination units. The second HDC write inhibit determination unit 413 includes second HDC write inhibit determination units 413G and 413H. Furthermore, the second HDC write inhibit determination unit 413 may include only one second HDC write inhibit determination unit, or may include three or more second HDC write inhibit determination units.

[0525] MPU50 includes MPU50G and 50H. HDC60 includes HDC60G and 60H. In addition, HDC60 may have only one HDC or more than three HDCs. Servo control unit 610 includes servo control units 610G and 610H. In addition, servo control unit 610 may have only one servo control unit or more than three servo control units. Tracking control unit 611 includes tracking control units 611G and 611H. In addition, tracking control unit 611 may have only one tracking control unit or more than three tracking control units. DPES demodulation unit 6111 includes DPES demodulation units 6111G and 6111H. DPES demodulation unit 6111 may have only one DPES demodulation unit or more than three DPES demodulation units. Tracking control unit 612 includes tracking control units 612G and 612H. The seek control unit 612 may have only one seek control unit or more than three seek control units. The write action determination unit 620 includes write action determination units 620G and 620H. The write action determination unit 620 may have only one write action determination unit or more than three write action determination units. The position write action determination unit 621 includes position write action determination units 621G and 621H. The position write action determination unit 621 may have only one position write action determination unit or more than three position write action determination units. The speed write action determination unit 622 includes speed write action determination units 622G and 622H. The speed write action determination unit 622 may have only one speed write action determination unit or more than three speed write action determination units.

[0526] The system controller 130G includes an R / W channel 40G, an MPU 50G, and an HDC 60G. The system controller 130G is electrically connected to the driver IC 20G, the head amplifier IC 30G, the volatile memory 70, the buffer memory 80, the non-volatile memory 90, the write inhibit detector 180, the controller communication unit 190, and the host system 700. The system controller 130G is electrically connected to the system controller 130G via transmission paths WR0 and WR1. Transmission paths WR0 and WR1 can be physical wiring, communication circuits, or conceptual paths for transmitting or transferring electricity, data, and information. Furthermore, the system controller 130G may include an SPM control unit 210G, a VCM control unit 220G, and an MA control unit 230G. The system controller 130G may also include the driver IC 20G and the head amplifier IC 30G.

[0527] The R / W channel 40G performs signal processing for read data transmitted from the disk DK4 to the host computer 700 and for write data transmitted from the host computer 700, based on instructions from the MPU 50G. The R / W channel 40G is electrically connected to, for example, the head amplifier IC 30G, the MPU 50G, the HDC 60G, and the write inhibit detector 180. The R / W channel 40G is connected to the write operation determination unit 620H (HDC 60H) via the transmission path WR1. Alternatively, the R / W channel 40G may not be connected to the write operation determination unit 620H (HDC 60H) via the transmission path WR1. The R / W channel 40G includes a write inhibit unit 410G.

[0528] The write inhibit unit 410G inhibits (or stops) writing (or writing operations) by the heads HD4 and HD5 via the HDCs 60G and 60H. The write inhibit unit 410G is connected to the write operation determination unit 620H (HDC 60H) via the transmission path WR1. Alternatively, the write inhibit unit 410G may not be connected to the write operation determination unit 620H (HDC 60H) via the transmission path WR1. The write inhibit unit 410G includes a vibration sensor write inhibit determination unit 411G, a first HDC write inhibit determination unit 412G, and a second HDC write inhibit determination unit 413G.

[0529] When vibration or impact is detected by the vibration sensor 170, the vibration sensor write prohibition determination unit 411G determines whether to prohibit (or stop) writing (or writing action) performed by the head HD4 of the actuator AC4 or not.

[0530] For example, when a write inhibit determination execution signal is received, the vibration sensor write inhibit determination unit 411G determines whether to prohibit (or stop) writing (or writing action) performed by at least one head HD corresponding to the actuator AC4 or not to prohibit (or stop) writing (or writing action).

[0531] For example, upon receiving a write inhibit determination execution signal, the vibration sensor write inhibit determination unit 411G determines whether the vibration or shock is greater than a predetermined value based on the write inhibit determination execution signal. For example, upon determining that the vibration or shock is greater than a predetermined value, the vibration sensor write inhibit determination unit 411G determines to inhibit (or stop) writing (or a write operation) to at least one head HD4 of the actuator AC4. For example, upon determining that the vibration or shock is greater than a predetermined value, the vibration sensor write inhibit determination unit 411G outputs a write inhibit determination signal to determine to inhibit (or stop) writing (or a write operation) to at least one head HD4 of the actuator AC4. For example, upon determining that the vibration or shock is less than a predetermined value, the vibration sensor write inhibit determination unit 411G does not determine to inhibit (or stop) writing (or a write operation) to at least one head HD4 of the predetermined actuator AC4.

[0532] The first HDC write inhibit determination unit 412G inhibits (or stops) writing (or the writing operation) of the head HD4 corresponding to the HDC 60G. For example, upon receiving a write inhibit signal from the HDC 60G to inhibit (or stop) writing (or the writing operation) of the head HD4, the first HDC write inhibit determination unit 412G negates (negates or deasser...

Claims

1. A magnetic disk device comprising: a first disk comprising a first servo sector and a first data sector different from the first servo sector; a second disk comprising a second servo sector and a second data sector different from the second servo sector; a first head comprising a first write head for writing data to the first disk and a first read head for reading data from the first disk; a second head comprising a second write head for writing data to the second disk and a second read head for reading data from the second disk; a first actuator having the first head; a second actuator having the second head; a first controller for stopping writing operations of both the first head and the second head based on first data sector position error information demodulated by the first read head reading the first data sector; and The second controller stops the writing operations of both the first head and the second head based on second data sector position error information demodulated by the second read head reading the second data sector.

2. The magnetic disk device according to claim 1, The invention comprises a housing and a first bearing, wherein the housing has a bottom wall, and the first bearing is vertically arranged on the bottom wall. The first actuator and the second actuator are rotatably mounted on the first bearing, respectively. The first controller controls the first actuator. The second controller controls the second actuator.

3. The magnetic disk device according to claim 1 or 2, The first data sector has a first preamble having a first recording frequency different from the recording frequencies of preambles of other data sectors arranged in the radial direction of the first disk. The second data sector has a second preamble having a second recording frequency that is different from the recording frequencies of preambles of other data sectors arranged in the radial direction of the second disk.

4. The magnetic disk device according to claim 3, In a plan view, the first disk and the second disk overlap. The first preamble and the second preamble are offset in the circumferential directions of the first disk and the second disk.

5. The magnetic disk device according to claim 3, The first controller calculates the position of the first head based on the amplitude and phase, or the sine component and cosine component, of the fundamental frequency of the first recording frequency of the first preamble. The second controller calculates the position of the second head based on the amplitude and phase, or the sine component and cosine component, of a fundamental frequency of a second recording frequency of the second preamble.

6. The magnetic disk device according to claim 1 or 2, The first data sector has a first pulse train having a first recording frequency different from the recording frequencies of pulse trains of other data sectors arranged in the radial direction of the first disk. The second data sector has a second pulse train having a second recording frequency that is different from the recording frequencies of pulse trains of other data sectors arranged in the radial direction of the second disk.

7. The magnetic disk device according to claim 6, In a plan view, the first disk and the second disk overlap. The first pulse train and the second pulse train are offset in the circumferential directions of the first disk and the second disk.

8. The magnetic disk device according to claim 6, The first controller calculates the position of the first head based on the amplitude and phase, or the sine component and cosine component, of the fundamental frequency of the first recording frequency of the first pulse train. The second controller calculates the position of the second head based on the amplitude and phase, or the sine component and cosine component, of a fundamental frequency of a second recording frequency of the second pulse train.

9. The magnetic disk device according to claim 1 or 2, The first data sector has a first Null burst having a recording frequency different from Null bursts of other data sectors arranged in the radial direction of the first disk. The second data sector has a second Null burst train having a recording frequency different from Null burst trains of other data sectors arranged in the radial direction of the second disk.

10. The magnetic disk device according to claim 1 or 2, The first controller performs self-servo writing on the first servo sector in the first disk. The second controller performs self-servo writing on the second servo sector on the second disk so that the second data sector is offset with respect to the first data sector in a circumferential direction of the first disk and the second disk.

11. The magnetic disk device according to claim 1, The invention comprises a housing, a first bearing and a second bearing, wherein the housing has a bottom wall, the first bearing and the second bearing are vertically arranged on the bottom wall, and the second bearing is different from the first bearing. The first actuator is rotatably mounted on the first bearing. The second actuator is rotatably mounted on the second bearing. The first controller controls the first actuator. The second controller controls the second actuator.

12. The magnetic disk device according to claim 1 or 2, The first controller stops writing operations of both the first head and the second head based on at least one of a current first position of the first head and an estimated first estimated position of the first head. The second controller stops the writing operations of both the first head and the second head based on at least one of a current second position of the second head and an estimated second estimated position of the second head.

13. The magnetic disk device according to claim 12, The first controller calculates the first estimated position based on the first position and a first speed of the first head at the first position. The second controller calculates the second estimated position based on the second position and a second speed of the second head at the second position.

14. The magnetic disk device according to claim 1 or 2, The first controller has a first read / write channel and a first hard disk controller, The second controller has a second read / write channel and a second hard disk controller. The first read / write channel is connected to the second hard disk controller via a first line. The second read / write channel is connected to the first hard disk controller via a second line.

15. The magnetic disk device according to claim 1 or 2, an information transmission unit connecting the first controller and the second controller, and transmitting vibration information including the first data sector position error information or the second data sector position error information and indicating that the first head and the second head have vibrated, to the first controller or the second controller; The first controller transmits the vibration information to the second controller via the information transmitting unit. The second controller transmits the vibration information to the first controller via the information transmitting unit.

16. The magnetic disk device according to claim 14, The first controller sets different data sector formats on the upper surface and the lower surface of the first disk. The second controller sets different data sector formats on the upper surface and the lower surface of the second disk.

17. The magnetic disk device according to claim 1 or 2, When one of the first head and the second head is in an idle state, the first controller and the second controller cause the other of the first head and the second head that is not in an idle state to perform servo tracking on the first disk or the second disk.

18. A magnetic disk device comprising: A disk having a first side and a second side, wherein the first side includes a first servo sector and a first data sector different from the first servo sector, and the second side includes a second servo sector and a second data sector different from the second servo sector; a first head comprising a first write head for writing data to the first side and a first read head for reading data from the first side; a second head comprising a second write head for writing data to the second side and a second read head for reading data from the second side; an actuator having the first head and the second head; a first controller for stopping writing operations of both the first head and the second head based on first data sector position error information demodulated by the first read head reading the first data sector; and The second controller stops the writing operations of both the first head and the second head based on second data sector position error information demodulated by the second read head reading the second data sector.

19. The magnetic disk device according to claim 18, The actuator includes a first suspension, a first microactuator, a second suspension, and a second microactuator. The first microactuator is mounted on the first suspension and independently drives the first head. The second microactuator is mounted on the second suspension and independently drives the second head.

20. The magnetic disk device according to claim 19, The first head has a third head different from the first head, and the third head reads data from the first surface. The second head includes a fourth head that is different from the second head, and the fourth head reads data from the second surface.

21. A method for stopping a write operation, the method being applied to a magnetic disk device, the magnetic disk device comprising: a first disk including a first servo sector and a first data sector different from the first servo sector; a second disk including a second servo sector and a second data sector different from the second servo sector; a first head including a first write head for writing data to the first disk and a first read head for reading data from the first disk; a second head including a second write head for writing data to the second disk and a second read head for reading data from the second disk; a first actuator having the first head; and a second actuator having the second head, wherein the method for stopping the writing operation includes: stopping writing operations of both the first head and the second head based on first data sector position error information demodulated by the first reading head when reading the first data sector; and Based on second data sector position error information demodulated by reading the second data sector by the second read head, the writing operations of both the first head and the second head are stopped.

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