Magnetic disk device

Abstract

Provided is a disk device capable of improving data format efficiency. The disk device includes a disk having a zoned servo area (ZBa) including a first region (RE1) having a first servo frequency, a second region (RE2) having a second servo frequency, and a third region (RE3) having the first servo frequency; a head; and a controller that demodulates first servo data of the first region, derives a position of the head, demodulates first correction data of the third region, and corrects the position of the head. The first region (RE1), the second region (RE2), and the third region (RE3) are arranged in order in a traveling direction (d2). The first region (RE1) and the second region (RE2) are adjacent to each other in a circumferential direction of the disk. The second region (RE2) and the third region (RE3) are adjacent to each other in the circumferential direction.

Description

[0001] This application claims priority to Japanese Patent Application No. 2022-034587 (filed on March 7, 2022). This application incorporates the entire contents of that basic application by reference. Technical Field

[0002] Embodiments of the present invention relate to disk drives. Background Technology

[0003] Disk devices include conventional magnetic recording (CMR) type (or conventional recording type) disk devices that write multiple tracks with spacing in the radial direction of the disk, shimmering magnetic recording (SMR or Shimmering Write Recording (SWR) type disk devices that overlap multiple tracks in the radial direction of the disk, and hybrid recording type disk devices that select between conventional recording type and shimmering recording type. Disks have servo areas such as a preamble area, a servo mark area, a Gray code area, and a postcode area. Conventional recording type, shimmering recording type, and hybrid recording type disk devices may each have a servo area containing the corresponding postcode area. Summary of the Invention

[0004] This embodiment provides a disk device that can improve data format efficiency.

[0005] One embodiment of a disk device includes: a disk having a servo region comprising a first region including a first servo frequency, a second region including a second servo frequency, and a third region including the first servo frequency; a head having a write head for writing data to the disk and a read head for reading data from the disk; and a controller that, in order to position the head in association with a predetermined track, demodulates first data read by the head in the first region to derive the position of the head, and demodulates third data read by the head in the third region to correct the position of the head, wherein the first region, the second region, and the third region are arranged sequentially in the direction of travel of the head relative to the disk, the first region and the second region are adjacent to each other, and the second region and the third region are adjacent to each other. Attached Figure Description

[0006] Figure 1 This is a block diagram illustrating the configuration of the disk device involved in the comparative example.

[0007] Figure 2 This is a schematic diagram illustrating an example of the configuration of the servo area of ​​the disk involved in the above comparative example.

[0008] Figure 3 This is a schematic diagram representing an example of the data pattern of the tracks on the aforementioned disk.

[0009] Figure 4 This is a schematic diagram representing other examples of the data patterns of the tracks on the aforementioned disk.

[0010] Figure 5 It means Figure 2 A schematic diagram of an example of a servo sector in the servo region shown.

[0011] Figure 6 This is a schematic diagram representing an example of a servo sector in the aforementioned servo region.

[0012] Figure 7 This is a schematic diagram representing other examples of servo sectors in the aforementioned servo region.

[0013] Figure 8 It means Figure 1 The block diagram shown is an example of the configuration of the head, head amplifier IC, and system controller.

[0014] Figure 9 This is a schematic diagram illustrating an example of the geometric configuration of the write head and two read heads in the aforementioned disk device, with the read head positioned at the reference position.

[0015] Figure 10 This is a schematic diagram illustrating an example of the geometric configuration of the write head and two read heads in the aforementioned disk device, where the read head is positioned at a radial position.

[0016] Figure 11 This is a schematic diagram illustrating an example of the geometric configuration of the write head and two read heads in the aforementioned disk device, where the read head is positioned at a radial position.

[0017] Figure 12 It means Figure 2 The schematic diagram shown is of a portion of the circumferential area of ​​the disk, representing a main servo area and two data areas.

[0018] Figure 13 This is a schematic diagram illustrating the servo sectors of the dual-zone servo region of the disk in the disk device according to the first embodiment.

[0019] Figure 14 This is a schematic diagram illustrating an example of front-side servo read processing in the dual-segment servo region of the disk according to the first embodiment described above.

[0020] Figure 15 This is a schematic diagram illustrating an example of rear-side servo read processing in the dual-segment servo region of the disk according to the first embodiment described above.

[0021] Figure 16 This is a schematic diagram illustrating an example of servo read processing in a single segment servo region of the disk according to the first embodiment described above.

[0022] Figure 17 This is a schematic diagram showing a portion of the disk in the circumferential direction according to the first embodiment described above, and a diagram showing a main servo area and two data areas.

[0023] Figure 18 This is a schematic diagram showing a portion of the servo area, gaps, and data segments arranged in the circumferential direction of the disk according to the first embodiment described above. It is also a diagram showing an example of a servo gate, a write gate, and a read gate.

[0024] Figure 19 The graphs used in the first embodiment and the comparative example described above respectively show the change in the proportion of format loss relative to the radius of the disk.

[0025] Figure 20 This is a flowchart illustrating an example of the write processing method for postfix codes according to the first embodiment described above.

[0026] Figure 21 This is a flowchart illustrating an example of the postcode reading processing method according to the first embodiment described above.

[0027] Figure 22 This is a schematic diagram showing a portion of the disk in the circumferential direction according to the first embodiment described above, and a diagram showing a servo area and two data areas.

[0028] Figure 23 This is a schematic diagram showing a portion of the disk in the circumferential direction of the disk device according to the second embodiment, and a diagram showing a main service area and two data areas.

[0029] Figure 24 This is a schematic diagram showing a portion of the disk in the circumferential direction according to the second embodiment described above, and a diagram showing a servo area and two data areas.

[0030] Label Explanation

[0031] 1 disk device, 10 disks, 12 spindle motors (SPM), 13 arms, 14 voice coil motors (VCM), 15 heads, 15W write head, 15R read head, 20 drive ICs, 30 head amplifier ICs, 40 read / write (R / W) channels, 50 hard disk controller (HDC), 60 microprocessor (MPU), 130 system controller, SV servo area, ZB dual-segment servo area, ZG single-segment servo area, ZSV segment servo area, RE1 first segment, RE2 second segment, RE3 third segment, RE4 fourth segment, RE5 fifth segment, RO1 first object segment, NRO1 first non-object segment, RO2 second object segment, NRO2 second non-object segment, RO3 third object segment, NRO3 third non-object segment, DTR user data area (data area), DZ data segment area, DSC data sector, TS track skip (track) skip) area, d1 radius direction, d2 travel direction, d3 rotation direction, ID inner perimeter, OD outer perimeter. Detailed Implementation

[0032] (Comparative Example)

[0033] First, the comparative examples will be explained with reference to the accompanying drawings. Figure 1 This is a block diagram illustrating the configuration of the disk device 1 involved in this comparative example.

[0034] like Figure 1 As shown, the disk drive 1 includes a head disk assembly (HDA), a driver IC 20, a head amplifier integrated circuit (hereinafter referred to as a head amplifier IC or preamplifier) ​​30, volatile memory 70, non-volatile memory 80, buffer memory (cache) 90, and a system controller 130 as a single-chip integrated circuit. Furthermore, the disk drive 1 is connected to a host system (hereinafter referred to as a host) 100.

[0035] The HDA includes a disk (hereinafter referred to as a disk) 10, a spindle motor (hereinafter referred to as a SPM) 12, an arm 13 with a head 15 mounted on it, and a voice coil motor (hereinafter referred to as a VCM) 14. The disk 10 is mounted on the SPM 12 and rotates under the drive of the SPM 12. The arm 13 and the VCM 14 constitute an actuator. The actuator, driven by the VCM 14, moves the head 15 mounted on the arm 13 to a predetermined position on the disk 10. Two or more disks 10 and heads 15 may be provided.

[0036] Disk 10 allocates a user data area 10a that can be used by the user, a media cache (or sometimes called a media cache area) 10b that temporarily holds data (or commands) transmitted from the host or other sources before writing them to a predetermined area of ​​the user data area 10a, and a system area 10c that writes information required for system management. Alternatively, the media cache 10b may not be configured on disk 10.

[0037] Hereinafter, the direction from the inner circumference to the outer circumference of disk 10 will be called the radial direction. In the direction parallel to the radial direction, the direction from the inner circumference to the outer circumference will be called the outer direction (outer side), and the direction from the outer circumference to the inner circumference will be called the inner direction (inner side). The direction orthogonal to the radial direction of disk 10 will be called the circumferential direction or circumferential direction. The circumferential direction is equivalent to the direction along the circumference of disk 10.

[0038] In addition, the predetermined position in the radial direction of disk 10 is sometimes referred to as the radial position, and the predetermined position in the circumferential direction of disk 10 is referred to as the circumferential position. Sometimes, the radial position and the circumferential position are simply referred to as position. The radial position is, for example, the distance from the rotation center of 10 to the predetermined radial position, the distance from the innermost circumference of disk 10 to the predetermined radial position, or the distance from the predetermined radial position of disk 10 to other radial positions, etc.

[0039] Disk 10 is divided into multiple zones (sometimes referred to as zones) along a predetermined radius. Each zone contains multiple tracks. Sometimes, the region obtained by dividing disk 10 radially is also called a radial region. A radial region includes zones, tracks, etc.

[0040] In addition, "track" can refer to one of the multiple regions of disk 10 that are divided in the radial direction, the path of head 15 at a predetermined radial position, data that extends in the circumferential direction of disk 10, a circumference of data written in a track at a predetermined radial position, data written in a predetermined track of disk 10, a portion of data written in a predetermined track of disk 10, and various other meanings.

[0041] The term "sector" is used to refer to one of several regions obtained by dividing a predetermined track of disk 10 in a circumferential direction, data written at a predetermined circumferential position at a predetermined radius position of disk 10, data written in a predetermined sector of a predetermined track of disk 10, and various other meanings.

[0042] Sometimes the "width in the radial direction of a track" is referred to as the "track width." Sometimes the "path through the center of the track width in a predetermined track" is referred to as the "track center." Sometimes the "width in the radial direction of a sector" is referred to as the "sector width." Sometimes the "path through the center of the sector width in a predetermined sector" is referred to as the "sector center." The sector center coincides with the track center. The terms "same," "identical," "consistent," and "equivalent" naturally include the meaning of being completely identical, as well as the meaning of being different to a degree that can be considered substantially identical. Hereinafter, the "track center of a predetermined track" will sometimes be simply referred to as the "track." In addition, the "sector center of a predetermined sector" will sometimes be simply referred to as the "sector."

[0043] The head 15 has a slider as its main body and includes a write head 15W and a read head 15R mounted on the slider. The write head 15W writes data onto the disk 10. Hereinafter, "writing data" will sometimes be referred to as "writing," "data writing," "write processing," etc. The read head 15R reads the data recorded on the disk 10. Hereinafter, "reading data" will sometimes be referred to as "reading," "data reading," "read processing," etc.

[0044] In addition, sometimes the write head 15W is simply referred to as head 15, sometimes the read head 15R is simply referred to as head 15, and sometimes both the write head 15W and the read head 15R are referred to as head 15. Sometimes the center of head 15 is simply referred to as head 15, the center of the write head 15W is simply referred to as write head 15W, and the center of the read head 15R is simply referred to as read head 15R.

[0045] Sometimes "writing to the center of head 15W" is simply referred to as "head 15", and sometimes "reading from the center of head 15R" is simply referred to as "head 15". Sometimes "positioning the center of head 15 in the center of a predetermined track" is also expressed as "positioning head 15 in a predetermined track", "arranging head 15 in a predetermined track", "positioning head 15 in a predetermined track", etc.

[0046] Figure 2 This is a schematic diagram illustrating an example of the configuration of the servo area SV of disk 10 involved in this comparative example. (See diagram below.) Figure 2 As shown, in the radial direction d1, the direction towards the outer periphery of disk 10 is called the outer direction (outer side), and the direction opposite to the outer direction is called the inner direction (inner side). Additionally, as... Figure 2 As shown, the direction in which disk 10 rotates in the circumferential direction is called the rotation direction d3. Furthermore, in Figure 2 In the example shown, the rotation direction d3 is represented by a counterclockwise direction, but it can also be the opposite direction (clockwise).

[0047] Furthermore, the direction of travel d2 of the head 15 relative to the disk 10 is opposite to the direction of rotation d3. The direction of travel d2 is the direction in which the head 15 writes and reads data from the disk 10 in a sequential manner in the circumferential direction, that is, the direction in which the head 15 travels relative to the disk 10 in the circumferential direction.

[0048] exist Figure 2 In the data region 10a, the user data region is divided into an inner peripheral region IR located in the inward direction, an outer peripheral region OR located in the outward direction, and a middle peripheral region MR located between the inner peripheral region IR and the outer peripheral region OR.

[0049] Disk 10 has multiple servo sectors (SVs) and multiple data sectors (DTRs). The multiple servo sectors (SVs) may extend radially in the radial direction of disk 10 and be discretely arranged with predetermined intervals in the circumferential direction. Alternatively, the multiple servo sectors (SVs) may extend linearly from the inner circumference to the outer circumference and be discretely arranged with predetermined intervals in the circumferential direction. Alternatively, the multiple servo sectors (SVs) may extend spirally from the inner circumference to the outer circumference and be discretely arranged with predetermined intervals in the circumferential direction. Furthermore, the multiple servo sectors (SVs) may be arranged in an island shape in the radial direction and discretely arranged with varying predetermined intervals in the circumferential direction. Hereinafter, a servo sector (SV) within a predetermined track is sometimes referred to as a "servo sector." Additionally, a "servo sector (SV)" is sometimes referred to as a "servo sector SV." A servo sector contains servo data. Hereinafter, the "configuration of several servo data constituting a servo sector" is sometimes referred to as a "servo mode." Furthermore, the "servo data written in a servo sector" is sometimes referred to as a "servo sector."

[0050] Multiple Data Regions (DTRs) are configured between multiple Servo Regions (SVs). For example, a Data Region DTR corresponds to the area between two consecutive Servo Regions (SVs) in the circumferential direction. Hereinafter, a Data Region DTR within a predetermined track is sometimes referred to as a "data sector." Furthermore, a "Data Region DTR" is sometimes referred to as a "Data Sector DTR." Data sectors contain user data. Additionally, "user data written in a data sector" is sometimes referred to as a "data sector." Sometimes, a "data sector" is also referred to as "user data." Furthermore, a "pattern consisting of several data items" is sometimes referred to as a "data pattern." Figure 2 In the example shown, the data pattern of the predetermined track consists of servo data (servo sector) and user data (data sector).

[0051] A servo region SV has multiple segmented servo regions ZSVs, etc. In addition to segmented servo regions ZSVs, a servo region SV may also include regions containing gaps (the deviation in circumferential position between two segmented servo regions), regions containing servo data, and data regions DTRs, etc. Multiple segmented servo regions ZSVs are discretely arranged along the radial direction. Each of the multiple segmented servo regions ZSVs extends in the radial direction.

[0052] Sometimes, a segment servo region (servo area) ZSV within a predetermined track is referred to as a "segment servo sector" or "servo sector". Furthermore, the "segment servo region (servo area) ZSV" is sometimes referred to as a "segment servo sector ZSV" or "servo sector ZSV". Sometimes, "servo data written within a segment servo sector" is also referred to as a "segment servo sector" or "servo sector". Hereinafter, "the configuration of several servo data constituting a segment servo sector" is sometimes referred to as a "segment servo mode" or "servo mode". Hereinafter, a servo region SV within a predetermined track is sometimes referred to as a "segment mode sector".

[0053] In addition, "servo zone SV" is sometimes referred to as "segment mode sector". "At least one piece of data written in a segment mode sector" is sometimes also referred to as "segment mode sector". A segment mode sector contains at least one segment servo sector. Hereinafter, "the data mode of a segment mode sector" will sometimes be referred to as "segment data mode".

[0054] In a predetermined servo region SV, the servo frequency of the outward-oriented segment servo regions within a plurality of segment servo regions ZSV arranged from the inside out is greater than the servo frequency of the inward-oriented segment servo regions within these plurality of segment servo regions ZSV. Furthermore, the servo frequency of the outward-oriented segment servo sectors within a predetermined segment servo region ZSV is greater than the servo frequency of the inward-oriented segment servo sectors within that segment servo region ZSV. Regarding the linear velocity (travel speed) of the head 15 relative to the disk 10, the radial position in the outward direction is faster than the radial position in the inward direction. Therefore, as described above, by making the servo frequency of the servo regions in the outward direction greater than the servo frequency of the servo regions in the inward direction within the disk 10, formatting efficiency can be improved. Moreover, the servo frequency is the frequency at which servo data is written to or read from the servo region.

[0055] exist Figure 2 In the example shown, the servo region SV has segmented servo regions ZSV0, ZSV1, and ZSV2. The segmented servo regions ZSV0, ZSV1, and ZSV2 are arranged in an alternating pattern in the radial direction. Alternatively, the segmented servo regions ZSV0, ZSV1, and ZSV2 can be arranged in a stepped pattern in the radial direction.

[0056] Segment servo region ZSV2 is located inwards from segment servo region ZSV1. Segment servo region ZSV0 is located outwards from segment servo region ZSV1. For example, segment servo region ZSV2 is configured from the inner peripheral region IR to the middle peripheral region MR, segment servo region ZSV1 is configured from the inner peripheral region IR to the outer peripheral region OR, and segment servo region ZSV0 is configured from the middle peripheral region MR to the outer peripheral region OR. Hereinafter, in the predetermined servo region SV, the predetermined region in the radial direction where multiple segment servo regions ZSV are configured in the circumferential direction is sometimes referred to as the segment servo boundary region, dual servo region, or dual segment servo region ZB.

[0057] The segment servo region ZSV2 is configured on track TRz1. The outer periphery of segment servo region ZSV2 and the inner periphery of segment servo region ZSV1 are configured on track TRn. In other words, the outer periphery of segment servo region ZSV2 and the inner periphery of segment servo region ZSV1 are configured on dual segment servo region ZB2.

[0058] Segment servo region ZSV1 is configured on track TRz2. The outer periphery of segment servo region ZSV1 and the inner periphery of segment servo region ZSV0 can be configured on track TRm. In other words, the outer periphery of segment servo region ZSV1 and the inner periphery of segment servo region ZSV0 are configured on dual segment servo region ZB1. Segment servo region ZSV0 is configured on track TRz3.

[0059] For example, the servo frequency of segment servo region ZSV1 is greater than that of segment servo region ZSV2, and the servo frequency of segment servo region ZSV0 is greater than that of segment servo region ZSV1. Furthermore, the servo frequency is the same as the frequency of the preamble, which will be described later.

[0060] A servo region SV may have a servo region (hereinafter sometimes also referred to as a master servo region) SVO and a servo region (hereinafter sometimes also referred to as a slave servo region) SVE. Hereinafter, a master servo region SVO in a predetermined track is sometimes referred to as a "master segment mode sector SVO", and a slave servo region SVE in a predetermined track is sometimes referred to as a "slave segment mode sector SVE".

[0061] Furthermore, the master servo region SVO is sometimes referred to as the "master segment mode sector SVO," while the slave servo region SVE is sometimes referred to as the "slave segment mode sector SVE." The data mode of the master segment mode sector (hereinafter sometimes referred to as the master segment data mode) can be the same as or different from the data mode of the slave segment mode sector (hereinafter sometimes referred to as the slave segment data mode).

[0062] exist Figure 2In the example shown, the master servo regions SVO and slave servo regions SVE are arranged alternately with a circumferential gap. For example, a slave servo region SVE is configured between two consecutive master servo regions SVO arranged with a circumferential gap. In other words, a slave servo region SVE is configured between two consecutive master servo regions SVO arranged with a circumferential gap. For example, when all servo regions SV of disk 10 are assigned consecutive numbers in sequence, the master servo region SVO corresponds to the odd-numbered servo region SV, and the slave servo region SVE corresponds to the even-numbered servo region SV. Furthermore, more than two slave servo regions SVE can be configured between two consecutive master servo regions SVO arranged with a circumferential gap.

[0063] The master servo region (SVO) and slave servo region (SVE) may, for example, consist solely of a servo region that reads and demodulates servo data as a whole (hereinafter sometimes referred to as a normal servo region). Hereinafter, "reading and demodulating servo data" is sometimes referred to as "servo reading." The master servo region (SVO) and slave servo region (SVE) may, for example, consist of a normal servo region and a servo region that reads servo data in a smaller circumferential direction compared to the servo data read in the normal servo region (hereinafter sometimes referred to as a short servo region).

[0064] For example, the master servo region (SVO) can also be composed of regular servo regions, and the slave servo region (SVE) can also be composed of short servo regions. Additionally, for example, the master servo region (SVO) can also be composed of short servo regions, and the slave servo region (SVE) can also be composed of regular servo regions.

[0065] Hereinafter, a normal servo region within a predetermined track is sometimes referred to as a "normal servo sector," and a short servo region within a predetermined track is sometimes referred to as a "short servo sector." Furthermore, the term "servo data in a normal servo sector" is sometimes used interchangeably with "servo data in a short servo sector."

[0066] In addition, "normal servo data" is sometimes referred to as "normal servo sector," and "short servo data" is sometimes referred to as "short servo sector." The servo mode of normal servo data (hereinafter sometimes referred to as normal servo mode) can be the same as or different from the servo mode of short servo sector (hereinafter sometimes referred to as short servo mode).

[0067] For example, the circumferential length of a short servo sector is shorter than the circumferential length of a typical servo sector. Hereinafter, "circumferential length" will sometimes be simply referred to as "length". Furthermore, the length of a short servo sector can be either the same as or longer than the length of a typical servo sector.

[0068] Next, refer to Figure 3 and Figure 4 This is an example of a data pattern representing a predetermined track in the dual-segment servo area ZB of disk 10. Figure 3 This is a schematic diagram representing an example of the data pattern ZDTP1 of track TRn on disk 10.

[0069] like Figure 3 As shown, the travel direction d2 and the rotation direction d3 are along the circumferential direction. The travel direction d2 is the direction in which the head 15 sequentially writes and reads data from the disk 10 in the circumferential direction. The track TRn has a data mode ZDTP1. The data mode ZDTP1 consists of the segment mode sector ZPS (ZPS1) and the data sector DSC of the data area DTR.

[0070] exist Figure 3 In the example shown, a segment mode sector ZPS1 is configured between two data sectors DSC arranged with an open interval in the travel direction d2 in data mode ZDTP1. Segment mode sector ZPS1 includes segment data mode ZDP1. Segment data mode ZDP1 consists of at least one data, such as segment servo sector ZSVS11 of segment servo region ZSV (ZSV1), gap (hereinafter sometimes also referred to as segment servo gap) GP (GP21), and segment servo sector ZSVS21 of segment servo region ZSV (ZSV2). In segment data mode ZDP1, segment servo sector ZSVS11, gap GP (GP21), and segment servo sector ZSVS21 are arranged in the travel direction d2 in the order described above.

[0071] Hereinafter, in a predetermined segment data mode, the predetermined segment servo sector positioned ahead of the predetermined segment servo sector in the rotation direction d3 is sometimes referred to as the "front segment servo sector," and the predetermined segment servo sector positioned behind the predetermined segment servo sector in the rotation direction d3 is sometimes referred to as the "rear segment servo sector." The front segment servo sector ZSVS11 includes the segment servo mode ZSP11. Additionally, the rear segment servo sector ZSVS21 includes the segment servo mode ZSP21.

[0072] For example, the length ZSSL11 of the front segment servo sector ZSVS11 is shorter than the length ZSSL21 of the rear segment servo sector ZSVS21. The length GPL2 (GPL) of the gap GP21 (GP) is equivalent to the circumferential distance between the front segment servo sector ZSVS11 and the rear segment servo sector ZSVS21. For example, the length GPL2 varies accordingly with the length ZSSL11. The length GPL2 can be set so that even if a write is performed on the front segment servo sector ZSVS11, the length of the front segment servo sector ZSVS11 will not be overwritten in the rear segment servo sector ZSVS21.

[0073] Figure 4 This is a schematic diagram representing an example of the data pattern ZDTP2 of track TRm on disk 10.

[0074] like Figure 4 As shown, track TRm has a data mode ZDTP2. Data mode ZDTP2 consists of segment mode sector ZPS (ZPS2) and data sector DSC of data area DTR.

[0075] exist Figure 4 In the example shown, data pattern ZDTP2 is configured with a segment pattern sector ZPS2 between two data sectors DSC arranged with an open interval in the travel direction d2. The segment pattern sector ZPS2 contains the segment data pattern ZDP2. The segment data pattern ZDP2 consists of at least one data, such as the segment servo sector ZSVS12 of the segment servo region ZSV (ZSV1), the gap GP (GP11), and the segment servo sector ZSVS02 of the segment servo region ZSV (ZSV0).

[0076] In segment data mode ZDP2, segment servo sector ZSVS12, gap GP (GP11), and segment servo sector ZSVS02 are arranged in the travel direction d2 in the order described above. The front segment servo sector ZSVS12 contains segment servo mode ZSP12. Furthermore, the rear segment servo sector ZSVS02 contains segment servo mode ZSP02.

[0077] For example, the length ZSSL12 of the front segment servo sector ZSVS12 is longer than the length ZSSL02 of the rear segment servo sector ZSVS02. The length GPL1 (GPL) of the gap GP11 (GP) is equivalent to the circumferential distance between the front segment servo sector ZSVS12 and the rear segment servo sector ZSVS02. The length GPL1 can be... Figure 3The length GPL2 shown can be the same or different. For example, the length GPL1 can vary accordingly with the length ZSSL12. The length GPL1 can be set so that even if a write is performed to the previous segment servo sector ZSVS12, the length of the previous segment servo sector ZSVS12 will not be overwritten in the subsequent segment servo sector ZSVS02.

[0078] Figure 5 This is a schematic diagram representing an example of a servo sector SVS0 within a servo region SV. (See diagram below.) Figure 5 As shown, the servo sector SVS0 of the servo region SV includes the predetermined segment servo sector of the segment servo region ZSV0 (e.g., the rear segment servo sector ZSVS02, etc.), the predetermined segment servo sector of the segment servo region ZSV1 (e.g., the front segment servo sectors ZSVS11 and ZSVS12, etc.), and the predetermined segment servo sector of the segment servo region ZSV2 (e.g., the rear segment servo sector ZSVS21, etc.).

[0079] For example, servo sector SVS0 includes segment servo sector ZSVS11 of segment servo region ZSV1 of track TRn, segment servo sector ZSVS21 of segment servo region ZSV2 of track TRn, segment servo sector ZSVS12 of segment servo region ZSV1 of track TRm, segment servo sector ZSVS02 of segment servo region ZSV0 of track TRm, segment servo sector ZSV0 of segment servo region ZSV1 of track TRz1, segment servo sector ZSV1 of segment servo region ZSV1 of segment servo region ZSV2 of track TRz3.

[0080] Servo sector SVS0 contains servo mode SVP0. Servo mode SVP0 consists of at least one servo data, such as a preamble, a servo mark or servo address mark, a Gray code, a PAD, burst data, and an additional pattern. In servo mode SVP0, the preamble, servo mark, Gray code, PAD, burst data, and additional pattern are arranged in the travel direction d2 in the order described above.

[0081] For example, in servo mode SVP0, the preamble, servo flag, Gray code, PAD, burst data, and append mode are arranged sequentially in the travel direction d2 in the order described above.

[0082] In other words, in servo mode SVP0, the servo marker is located after the preamble and adjacent to it. Here, "adjacent" naturally includes data, objects, areas, and spaces arranged in a grounded manner, as well as arrangements with predetermined intervals.

[0083] Gray code is adjacent to the servo marker. PAD is adjacent to the Gray code. Burst data is adjacent to the PAD.

[0084] The append mode is located after and adjacent to the burst data. Alternatively, the servo sector SVS0 may not include an append mode. The append mode, for example, corresponds to a mode used to determine timing deviations when demodulating data written to disk 10. The phase data obtained from reading the append mode can, for example, be used to determine whether there is a timing deviation when reading the burst data.

[0085] Hereinafter, the term "timing" is sometimes used to mean "timing after a predetermined time from the timing obtained as a reference for reading predetermined data from the read head 15R" and "timing when the read head 15R is configured at a predetermined circumferential position".

[0086] The append mode is, for example, data different from the postcode described later. The frequency of the append mode is, for example, different from the frequency of the preamble. In other words, the frequency of the append mode is different from the frequency of the postcode. For example, the frequency of the append mode is the same as the frequency of the pulse train data, such as the frequency of the N-pulse train and the frequency of the Q-pulse train.

[0087] For example, the append mode is a 4-bit periodic mode written at a pulse train frequency. The phase of the append mode changes periodically in the circumferential direction. The append mode is a data mode written in the radial direction d1 of disk 10 with a period of one servo track and the phase is equal. In other words, the phase of the predetermined append mode is equal to the phase of the append mode adjacent to it in the radial direction.

[0088] exist Figure 5 The diagram shows the length ASL0 of the servo sector SVS0 and the length ADL of the append mode. The length ADL is, for example, shorter than the length of the postcode described later. Hereinafter, the length of the PAD and the length of the pulse train can be either constant or different.

[0089] Figure 6 This is a schematic diagram representing an example of a servo sector SVS1 within a servo region SV. (See diagram below.) Figure 6As shown, the servo sector SVS1 of the servo region SV includes predetermined segment servo sectors of segment servo region ZSV0, segment servo region ZSV1, and segment servo region ZSV2. For example, servo sector SVS1 includes segment servo sector ZSVS11 of segment servo region ZSV1 of track TRn, segment servo sector ZSVS21 of segment servo region ZSV2 of track TRn, segment servo sector ZSVS12 of segment servo region ZSV1 of track TRm, segment servo sector ZSVS02 of segment servo region ZSV0 of track TRm, segment servo sector ZSV0 of segment servo region ZSV1 of track TRz1, segment servo sector ZSV1 of segment servo region ZSV2 of track TRz3, and segment servo sector ZSV2 of segment servo region TRz3. Servo sector SVS1 includes servo mode SVP1.

[0090] Servo mode SVP1 consists of at least one servo data, such as a preamble, servo flag or servo address flag, Gray code, PAD, burst data, and postcode X1. In servo mode SVP1, the preamble, servo flag, Gray code, PAD, burst data, and postcode X1 are arranged in the travel direction d2 in the order described above.

[0091] For example, in servo mode SVP1, the preamble, servo flag, Gray code, PAD, burst data, and suffix X1 are arranged consecutively in the travel direction d2 in the order described above. The suffix is ​​located after the burst data and adjacent to it. Alternatively, servo sector SVS1 may not include the suffix X1.

[0092] exist Figure 6 The diagram shows the length ASL1 of the servo sector SVS1, the length SVL1 obtained by adding the preamble, servo flag, and Gray code, and the length PCLX1 of the postcode.

[0093] The preamble contains preamble information used to synchronize with the reproduced signal of the servo pattern, which consists of servo markers and Gray codes.

[0094] The servo tag (or servo address tag) contains servo tag information that indicates the start of the servo mode.

[0095] Gray code consists of the address of the predetermined track (cylinder address) and the address of the servo sector of the predetermined track.

[0096] The pulse train data is the relative position data (position error) used to detect the positional deviation (position error) of the head 15 relative to the center of the predetermined track in the radial direction d1 and / or circumferential direction. It consists of a repeating pattern of a predetermined period.

[0097] PAD contains PAD information for synchronization signals such as gaps and servo AGC.

[0098] The burst data is written in a data pattern with a period of one servo track on the radial direction d1 of disk 10, and the phase of the burst data is reversed by 180°. The servo track (servo cylinder) is the track that is used for write or read processing according to commands from the host 100, etc. The burst data is used, for example, to obtain the position of the head 15 in the radial direction d1 and / or circumferential direction (hereinafter sometimes referred to as the head position).

[0099] The burst data includes, for example, N-burst and Q-burst. The N-burst and Q-burst are written in a data pattern in which their phases are offset from each other by 90° in the radial direction d1 of disk 10.

[0100] The postcode contains data used to correct errors caused by jitter (Repeatable Run Out: RRO) during the writing of servo data to the disk 10, which is synchronized with the rotation of the disk 10. This data includes data on the path (sometimes referred to as the target path) of the track relative to the head 15, which is concentrically arranged with the disk 10, and errors such as skewness in the center of the track (hereinafter referred to as RRO correction data). Hereinafter, the area where the postcode data (RRO correction data) is written will sometimes be referred to as the postcode area, the RRO bit area, or the correction data storage area.

[0101] For ease of explanation, the error caused by the track skew relative to the target path due to RRO will sometimes be simply referred to as RRO. For example, suffixes are included in normal servo sectors. Additionally, suffixes can also be included in short servo sectors. Append patterns are included in short servo sectors. Additionally, append patterns can also be included in normal servo sectors. For example, a length PCLX1 is... Figure 5 The length of ADL is longer. The length of ASL1 is longer than... Figure 5 The length is ASL0. Alternatively, the length PCLX1 can also be... Figure 5 The length is below ADL. Alternatively, the length ASL1 can also be... Figure 5 The length is below ASL0.

[0102] Figure 7 This is a schematic diagram representing an example of a servo sector SVS2 within a servo region SV. (See diagram for example.) Figure 7As shown, the servo sector SVS2 of the servo region SV includes predetermined segment servo sectors of segment servo regions ZSV0, ZSV1, and ZSV2. For example, servo sector SVS2 includes segment servo sectors ZSVS11 of segment servo region ZSV1 of track TRn, segment servo sectors ZSVS21 of segment servo region ZSV2 of track TRn, segment servo sectors ZSVS12 of segment servo region ZSV1 of track TRm, segment servo sectors ZSVS02 of segment servo region ZSV0 of track TRm, segment servo sectors ZSV0 of segment servo region ZSV1 of track TRz1, segment servo sectors ZSV1 of segment servo region ZSV2 of track TRz3, and segment servo sectors ZSV2 of segment servo region TRz3. Servo sector SVS2 includes servo mode SVP2. Servo mode SVP2 consists of at least one servo data element, such as a preamble, servo flag, Gray code, PAD, burst data, append mode, and postcode X2. The postcode X2 can be combined with... Figure 6 The suffix X1 can be the same or different.

[0103] In servo mode SVP2, the preamble, servo marker, Gray code, PAD, burst data, append mode, and suffix X2 are arranged in the travel direction d2 in the order described above. For example, in servo mode SVP2, the preamble, servo marker, Gray code, PAD, burst data, append mode, and suffix X2 are arranged continuously in the travel direction d2 in the order described above. Alternatively, servo sector SVS2 may not include the append mode and suffix X2.

[0104] exist Figure 7 The diagram shows the length ASL2 of the servo sector SVS2 and the length PCLX2 of the suffix code X2. The length ASL2 is, for example, greater than... Figure 5 The length of ASL0 and Figure 6 The length ASL1 is larger. The length PCLX2, for example, can be both... Figure 6 The length PCLX1 is the same, or it can be smaller or larger than the aforementioned length PCLX1.

[0105] like Figure 1 As shown, the driver IC20 controls the driving of SPM12 and VCM14 according to the control of the system controller 130 (specifically, the MPU60 described later).

[0106] The head amplifier IC (preamplifier) ​​30 includes a read amplifier and a write driver. The read amplifier amplifies the read signal read from disk 10 and outputs it to the system controller 130 (specifically, the read / write (R / W) channel 40 described later). The write driver outputs a write current to head 15 corresponding to the signal output from R / W channel 40.

[0107] Volatile memory 70 is a semiconductor memory whose stored data is lost when the power supply is cut off. Volatile memory 70 stores data required for processing in various parts of disk drive 1. Volatile memory 70 is, for example, DRAM (Dynamic Random Access Memory) or SDRAM (Synchronous Dynamic Random Access Memory).

[0108] Non-volatile memory 80 is a semiconductor memory that records stored data even when the power supply is cut off. Non-volatile memory 80 is, for example, a NOR or NAND type flash ROM (Flash Read Only Memory).

[0109] The buffer memory 90 is a semiconductor memory that temporarily records data transmitted and received between the disk drive 1 and the host computer 100. Furthermore, the buffer memory 90 may be integrated with the volatile memory 70. Examples of buffer memory 90 include DRAM, SRAM (Static Random Access Memory), SDRAM, FeRAM (Ferroelectric Random Access Memory), and MRAM (Magnetoresistive Random Access Memory).

[0110] The system controller (controller) 130 is implemented, for example, using a large-scale integrated circuit (LSI) called a system-on-a-chip (SoC), which integrates multiple components onto a single chip. The system controller 130 includes a read / write (R / W) channel 40, a hard disk controller (HDC) 50, and a microprocessor (MPU) 60. The system controller 130 is electrically connected, for example, to a driver IC 20, a head amplifier IC 30, volatile memory 70, non-volatile memory 80, a buffer memory 90, and a host 100.

[0111] R / W channel 40, according to instructions from MPU 60 (described later), performs signal processing, such as modulation, demodulation, encoding, and decoding, for read data transferred from disk 10 to host 100 and write data transferred from host 100. R / W channel 40 has circuitry or functionality for measuring the signal quality of read data. R / W channel 40 detects various gates, such as write gates (corresponding to signals for writing data), read gates (corresponding to signals for reading data), and servo gates (corresponding to signals for reading servo data). R / W channel 40 performs write data signal processing according to write gates, read data signal processing according to read gates, and servo data signal processing according to servo gates. R / W channel 40 performs servo read processing, demodulating servo data from the read signal input by head amplifier IC 30, and write processing (outputting write data to head amplifier IC 30) for writing data to disk 10. R / W channel 40 performs servo read processing and read processing for reading data from disk 10. R / W channel 40 is electrically connected, for example, to head amplifier IC30, HDC50, and MPU60.

[0112] For example, R / W channel 40 performs servo reading on a predetermined area of ​​disk 10 according to a servo strobe that performs servo reading of servo sector data as a whole, and performs write processing on that area based on the servo data read according to the servo strobe. Hereinafter, "servo strobe that performs servo reading of servo sector data as a whole" is sometimes referred to as "normal servo gate". "Performing servo reading processing according to normal servo gate" is sometimes referred to as "normal servo reading" or "normal servo reading processing".

[0113] For example, R / W channel 40 performs servo reading on a servo sector in a predetermined area of ​​disk 10 based on a servo gating of servo data of a servo sector, such as a servo data range in the circumferential direction smaller than the range in the circumferential direction of servo data read by servo gating in the normal servo direction, and performs write processing on the area based on the servo data read by servo gating.

[0114] Hereinafter, "servo gating that reads a portion of the servo data in a servo sector, such as a circumferential range smaller than the range of servo data read by servo gating normally," is sometimes referred to as "Short ServoGate." "Performing servo read processing according to the Short ServoGate" is sometimes referred to as "Short Servo Read" or "Short Servo Read Processing."

[0115] Typically, the length of time (sometimes referred to as servo gating length) from transitioning to an assert (active, valid, or ON) state to a negate (inactive, invalid, or OFF) state differs between servo strobe and short servo strobe. For example, the servo strobe length of a typical servo strobe is longer than that of a short servo strobe.

[0116] For example, R / W channel 40 performs a normal servo read on a servo sector in a predetermined area of ​​disk 10, and performs read processing on that area based on the servo data read normally.

[0117] For example, R / W channel 40 can also perform short servo reads on servo sectors in a predetermined area of ​​disk 10, and perform read processing on that area based on the servo data obtained from the short servo reads.

[0118] R / W channel 40 performs normal servo read processing in a predetermined area of ​​disk 10. Furthermore, R / W channel 40 can also switch whether short servo read processing is performed in the predetermined area of ​​disk 10. Sometimes, the "mode of performing short servo read processing" is referred to as "Short Servo Mode." Additionally, "performing short servo read processing" is sometimes referred to as "turning short servo mode ON," and "not performing short servo read processing" is sometimes referred to as "turning short servo mode OFF." That is, R / W channel 40 can switch between ON and OFF short servo mode.

[0119] For example, the R / W channel 40 can also switch the short servo mode ON and OFF depending on whether it is in write processing mode (hereinafter sometimes referred to as write mode) or read processing mode (hereinafter sometimes referred to as read mode). Hereinafter, "write mode" and "read mode" will sometimes be referred to together as "access mode". The term "access" includes meanings such as "recording or writing data to a predetermined area of ​​disk 10", "reading or retrieving data from a predetermined area of ​​disk 10", and "moving the head 15, etc., to a predetermined area of ​​disk 10". That is, the R / W channel 40 can also switch the short servo mode ON and OFF according to the access mode.

[0120] HDC50 controls the data transfer between host 100 and R / W channel 40 according to instructions from MPU60 (described later). HDC50 outputs various strobes to R / W channel 40, such as write strobes, read strobes, and servo strobes, according to instructions from MPU60 (described later). For example, HDC50 generates a normal servo strobe and outputs it to R / W channel 40. A normal servo strobe is equivalent to a strobe used to read at least the preamble, servo flag, Gray code, PAD, and burst data. For example, HDC50 generates a short servo strobe and outputs it to R / W channel 40. A short servo strobe is equivalent to a strobe used to read at least the burst data without reading the preamble, servo flag, Gray code, and PAD. HDC50 is electrically connected to R / W channel 40, MPU60, volatile memory 70, non-volatile memory 80, buffer memory 90, etc.

[0121] MPU60 is the main controller that controls various parts of the disk drive 1. MPU60 controls VCM14 via driver IC20, performing servo control for positioning head 15. Additionally, MPU60 controls SPM12 via driver IC20 to rotate disk 10. MPU60 controls write operations that write data to disk 10 and selects the destination for saving the written data. Furthermore, MPU60 controls read operations that read data from disk 10 and controls the processing of the read data. MPU60 also manages the areas where data is recorded. MPU60 is connected to various parts of the disk drive 1. For example, MPU60 is electrically connected to driver IC20, R / W channel 40, HDC50, etc.

[0122] Figure 8 It means Figure 1 The block diagram shown is an example of the configuration of the head 15, the head amplifier IC30, and the system controller 130.

[0123] like Figure 8 As shown, the R / W channel 40 has a gating detection unit 410. The gating detection unit 410 detects whether various gating modes, such as write gating, read gating, and servo gating, are in an assertion state or a negation state.

[0124] For example, the gating detection unit 410 performs write processing if it detects that the write gating is asserted, and stops write processing if it detects that the write gating is negative. The gating detection unit 410 performs read processing if it detects that the read gating is asserted, and stops read processing if it detects that the read gating is negative. The gating detection unit 410 performs servo read processing if it detects that the servo gating is asserted, and stops servo read processing if it detects that the servo gating is negative. Furthermore, the gating detection unit 410 can also be located within the HDC50 or MPU60.

[0125] The HDC50 includes a gating generation unit 510. The gating generation unit 510 generates various gating signals, such as write gating, read gating, and servo gating, according to commands from the host 100 and instructions from the MPU60, and outputs them to the R / W channel 40, for example, the gating detection unit 410. Hereinafter, "activating a predetermined gating" is sometimes referred to as "asserting a predetermined gating." Additionally, "disabling a predetermined gating" is sometimes referred to as "denying a predetermined gating." "Asserting a predetermined gating" and "denying a predetermined gating" sometimes also include the meaning of "generating a predetermined gating." Furthermore, the gating generation unit 510 may also be included in the R / W channel 40 or the MPU60.

[0126] For example, the gating generation unit 510 generates a normal servo gating and outputs the normal servo gating to the gating detection unit 410. For example, the gating generation unit 510 generates multiple normal servo gatings and outputs multiple normal servo gatings to the gating detection unit 410.

[0127] For example, when the short servo mode is ON, the gating generation unit 510 generates a normal servo gating and a short servo gating, and outputs the normal servo gating and the short servo gating to the gating detection unit 410.

[0128] For example, when the short servo mode is OFF, the gating generation unit 510 generates a normal servo gating and outputs the normal servo gating to the gating detection unit 410. For example, when the short servo mode is OFF, the gating generation unit 510 generates multiple normal servo gatings and outputs multiple normal servo gatings to the gating detection unit 410.

[0129] Figure 9 This is a schematic diagram illustrating an example of the geometric configuration of the write head 15W and two read heads 15R1 and 15R2 in a disk device 1, where the read head 15R1 is positioned at a reference position (e.g., the radius of the peripheral region MR).

[0130] like Figure 9 As shown, the central portion WC of the write head 15W, the central portion RC1 of the read head 15R1, the central portion RC2 of the read head 15R2, and the intermediate portion MP located between the central portion RC1 of the read head 15R1 and the central portion RC2 of the read head 15R2 are shown.

[0131] Hereinafter, the circumferential spacing between the center portion RC1 of read head 15R1 and the center portion RC2 of read head 15R2 is sometimes referred to as the down track separation (DTS). The radial spacing between the center portion RC1 of read head 15R1 and the center portion RC2 of read head 15R2 is sometimes referred to as the cross track separation (CTS). The spacing between read head 15R and write head 15W, such as the circumferential spacing between the center portion RC1 of read head 15R1 and the center portion WC of write head 15W, the circumferential spacing between the center portion RC2 of read head 15R2 and the center portion WC of write head 15W, and the circumferential spacing between the intermediate portion MP and the center portion WC of write head 15W, is sometimes referred to as the read / write gap.

[0132] Hereinafter, the circumferential gap between the center portion RC2 of the read head 15R2 and the center portion WC of the write head 15W will be described as the read / write gap Grw. For ease of explanation, the "center portion of the write head" and "each part of the write head" will sometimes be simply referred to as the "write head", and the "center portion of the read head", "the middle portion of two read heads among multiple read heads", and "each part of the read head" will be simply referred to as the "read head".

[0133] exist Figure 9 In the example shown, with the read head 15R1 positioned at the reference position, the write head 15W, read head 15R2, intermediate section MP, and read head 15R1 are arranged along the travel direction d2. With the read head 15R1 positioned at the reference position, the read / write gap Grw is a distance Grwb. With the read head 15R1 positioned at the reference position, the track spacing DTS is a distance DTSb.

[0134] Furthermore, the distance Grwb is equivalent to the straight-line distance from the center WC to the center RC2. The distance DTSb is equivalent to the straight-line distance from the center RC2 to the center RC1.

[0135] exist Figure 9 In the example shown, with the read head 15R1 positioned at the reference position, the write head 15W, read head 15R1, read head 15R2, and intermediate part MP do not deviate in the radial direction d1. With the read head 15R1 positioned at the reference position, the cross-track interval CTS is the distance CTSb, where distance CTSb = 0. Furthermore, with the read head 15R1 positioned at the reference position, the write head 15W, read head 15R1, read head 15R2, and intermediate part MP can each deviate in the radial direction d1.

[0136] Figure 10 This is a schematic diagram illustrating an example of the geometric configuration of the write head 15W and two read heads 15R1 and 15R2, in which the read head 15R1 is positioned at the radius of the inner peripheral region IR (e.g., the radius of the inner peripheral region IR) in the disk device 1.

[0137] like Figure 10 As shown, the central portions RC1, RC2, and WC are located on the inner periphery ID side of disk 10, closer to the reference position. The radius of the inner periphery region IR is also located on the inner periphery ID side, closer to the reference position.

[0138] With the read head 15R1 positioned at the radius of the inner peripheral region IR, the write head 15W, read head 15R1, read head 15R2, and intermediate part MP (head 15) are tilted towards the inner peripheral ID side at an oblique angle θsw = θswi relative to the axis extending in the circumferential direction. With the read head 15R1 positioned at the radius of the inner peripheral region IR, the read / write gap Grw is the distance Grwi. With the read head 15R1 positioned at the radius of the inner peripheral region IR, the track spacing DTS is the distance DTSi.

[0139] In addition, Grwi=Grwb·cosθswi, DTSi=DTSb·cosθswi.

[0140] exist Figure 10 In the example shown, with the read head 15R1 positioned at the radius of the inner peripheral region IR, the write head 15W, read head 15R1, read head 15R2, and intermediate portion MP are offset in the radial direction d1. With the read head 15R1 positioned at the radius of the inner peripheral region IR, the cross-channel spacing CTS is the distance CTSi.

[0141] In addition, CTSi=DTSb·sinθswi.

[0142] Figure 11 This is a schematic diagram illustrating an example of the geometric configuration of the write head 15W and the two read heads 15R1 and 15R2, in which the read head 15R1 is positioned at the radius of the outer peripheral region OR (e.g., the radius of the outer peripheral region OR) in the disk device 1.

[0143] like Figure 11 As shown, the central portions RC1, RC2, and WC are located on the outer periphery OD side of disk 10, which is closer to the reference position. The radius of the outer periphery region OR is also located on the outer periphery OD side, which is closer to the reference position.

[0144] exist Figure 11In the example shown, with the read head 15R1 positioned at the radius of the outer peripheral region OR, the write head 15W, read head 15R1, read head 15R2, and intermediate part MP (head 15) are tilted towards the outer peripheral OD side at an oblique angle θsw = θswo relative to the axis extending in the circumferential direction. With the read head 15R1 positioned at the radius of the outer peripheral region OR, the read / write gap Grw is the distance Grwo. With the read head 15R1 positioned at the radius of the outer peripheral region OR, the track spacing DTS is the distance DTSo.

[0145] In addition, Grwo=Grwb·cosθswo, and DTSo=DTSb·cosθswo.

[0146] exist Figure 11 In the example shown, with the read head 15R1 positioned at the radius of the outer peripheral region OR, the write head 15W, read head 15R1, read head 15R2, and intermediate part MP are offset in the radial direction d1. With the read head 15R1 positioned at the radius of the outer peripheral region OR, the cross-track spacing CTS is the distance CTSo.

[0147] In addition, CTSo=DTSb·sinθswo.

[0148] Next, a portion of disk 10 will be explained. Figure 12 It means Figure 2 The schematic diagram of a portion of the circumferential region in disk 10 shown is a diagram representing a main servo region SVO and two data regions DTR.

[0149] like Figure 12 As shown, the main servo region SVO, which serves as the servo region SV, has multiple segmented servo regions ZSV0, ZSV1, and ZSV2. Each segmented servo region ZSV0, ZSV1, and ZSV2 contains servo data other than the postcode.

[0150] The suffix code region PC0 is located after and adjacent to the segment servo region ZSV0. The suffix code of the suffix code region PC0 is used to correct the position of the first 15 when demodulating the servo data of the segment servo region ZSV0.

[0151] The postcode region PC1 is located behind and adjacent to the segment servo region ZSV1. The postcode of the postcode region PC1 is used to correct the position of the head 15 when demodulating the servo data of the segment servo region ZSV1.

[0152] The postcode region PC2 is located behind and adjacent to the segment servo region ZSV2. The postcode of the postcode region PC2 is used to correct the position of the head 15 when demodulating the servo data of the segment servo region ZSV2.

[0153] Within the main servo region SVO, multiple single-segment servo regions ZG and multiple double-segment servo regions ZB are arranged in the radial direction d1. Each single-segment servo region ZG is a region in which no multiple segment servo regions ZSV are arranged in the circumferential direction, and each double-segment servo region ZB is a region in which multiple segment servo regions ZSV are arranged in the circumferential direction.

[0154] The segment servo region ZSV2 and the postcode region PC2 have the same servo frequency, the segment servo region ZSV1 and the postcode region PC1 have the same servo frequency, and the segment servo region ZSV0 and the postcode region PC0 have the same servo frequency.

[0155] The servo frequencies of segment servo regions ZSV1 and PC1 (with postcode) are greater than those of segment servo regions ZSV2 and PC2 (with postcode). The servo frequencies of segment servo regions ZSV0 and PC0 (with postcode) are greater than those of segment servo regions ZSV1 and PC1 (with postcode).

[0156] Each data region DTR has multiple data segment regions DZ. Taking the data region DTR located behind the main servo region SVO as an example, the data region DTR has multiple data segment regions DZ from the data segment region DZ0 on the outer perimeter OD side to the data segment region DZ25 on the inner perimeter ID side.

[0157] In the figure, in the circumferential direction, multiple data segment regions DZ adjacent to the single segment servo region ZG are marked with dot patterns, and multiple data segment regions DZ adjacent to the dual segment servo region ZB are marked with diagonal lines pointing to the upper right.

[0158] Considering the area traversing the data segment region DZ7 in the circumferential direction, the following regions are arranged sequentially along the travel direction d2: data segment region DZ, segment servo region ZSV1, gap GP (GP1), segment servo region ZSV0, postcode region PC0, and data segment region DZ7. Gap GP1 includes... Figure 4 The gap GP11 is shown.

[0159] Considering the area passing through the data segment region DZ8 in the circumferential direction, the data segment region DZ, the segment servo region ZSV1, the postcode region PC1, the segment servo region ZSV0, the gap GP (GP3), and the data segment region DZ8 are arranged sequentially in the travel direction d2.

[0160] Considering the area passing through the data segment region DZ17 in the circumferential direction, the data segment region DZ, the segment servo region ZSV1, the postcode region PC1, the segment servo region ZSV2, the gap GP (GP4), and the data segment region DZ17 are arranged sequentially in the travel direction d2.

[0161] Considering the passage of data segment region DZ18 in the circumferential direction, the following are arranged sequentially along the travel direction d2: data segment region DZ, segment servo region ZSV1, gap GP (GP2), segment servo region ZSV2, postcode region PC2, and data segment region DZ18. Gap GP2 includes... Figure 3 The gap GP21 is shown.

[0162] In the figure, the dot pattern is marked more densely than the data segment region DZ in the gaps GP1 to GP4.

[0163] Based on the comparative example of disk device 1 configured as described above, considering that disk device 1 employs a segment servo system, the dual segment servo region ZB is utilized as a special data region. Regarding the linear velocity of the head 15 relative to the disk 10, the radius position on the outer perimeter OD side is faster than the radius position on the inner perimeter ID side. Therefore, by making the servo frequency of the servo region on the outer perimeter OD side of the disk 10 higher than the servo frequency of the servo region on the inner perimeter ID side, as described above, formatting efficiency can be improved.

[0164] In the dual-segment servo region ZB1, the front segment servo region ZSV1 and the rear segment servo region ZSV0 are arranged in a circumferential direction. In the dual-segment servo region ZB2, the front segment servo region ZSV1 and the rear segment servo region ZSV2 are arranged in a circumferential direction.

[0165] To write a postcode to the postcode region PC1, a gap GP1 is ensured between segment servo regions ZSV1 and ZSV0, and a gap GP2 is ensured between segment servo regions ZSV1 and ZSV2. In other words, gap GP1 prevents the following situation: when a postcode is written to the postcode region PC1, the servo data in segment servo region ZSV0 is erased. Similarly, gap GP2 prevents the following situation: when a postcode is written to the postcode region PC1, the servo data in segment servo region ZSV2 is erased.

[0166] In this comparative example, gaps GP1 and GP2 exist in the dual-segment servo region ZB. Therefore, the servo occupancy rate in the dual-segment servo region ZB increases, and the data volume in the dual-segment servo region ZB decreases. If gaps GP1 and GP2 can be eliminated, the data volume in the dual-segment servo region ZB can be increased. However, when gaps GP1 and GP2 are eliminated, it becomes impossible to write a postcode to the postcode region PC1 immediately after the pulse train data contained in the preceding segment servo region ZSV1.

[0167] Therefore, in order to solve the problem in this comparative example, in the embodiments described later, by reducing the gap between the dual-segment servo regions, a disk device that can reduce the servo occupancy rate of the dual-segment servo regions and improve data format efficiency can be obtained. For example, a disk device employing a servo format in which, in the dual-segment servo regions of the embodiments described later, a suffix region is provided immediately after the preceding segment servo region, rather than immediately after the preceding segment servo region. Furthermore, a disk device employing an adjacent data format that does not erase the suffix of the aforementioned suffix region can be obtained. Next, means and methods for solving the above-mentioned problems will be described. Furthermore, these means and methods are applied to the servo format of the dual-segment servo regions and the data format of the data regions.

[0168] (First Embodiment)

[0169] Next, the first embodiment will be described. The disk drive 1 is configured the same as the comparative example described above, except that the configuration described in this embodiment is the same. Figure 13 This is a schematic diagram used to explain the servo sector SVS1 of the dual-segment servo region ZB of the disk device 1 1 according to this embodiment. Figure 13 In order to compare with the servo sector SVS1 of this embodiment, the servo sector SVS1 of the comparative example is also shown.

[0170] like Figure 13 As shown, in the comparative example's servo sector SVS1, a gap GP exists between segment servo sector ZSVS01 and segment servo sector ZSVS11. On the other hand, in the servo sector SVS1 of this embodiment, the gap between segment servo sector ZSVS01 and segment servo sector ZSVS11 is eliminated. Figure 13The diagram illustrates an example of a servo mode for a servo sector with a specific track within a dual-segment servo region ZB before the postcode is written. The preceding segment servo sector ZSVS01 contains preamble 1, servo marker 1, Gray code 1, burst data 1, and append mode 1. The following segment servo sector ZSVS11 contains preamble 2, servo marker 2, Gray code 2, burst data 2, and append mode 2.

[0171] In the comparative example's servo sector SVS1, preamble 1, servo marker 1, Gray code 1, burst data 1, append mode 1, gap GP, preamble 2, servo marker 2, Gray code 2, burst data 2, and append mode 2 are arranged sequentially along the travel direction d2. Furthermore, append mode 1 and append mode 2 are modes used to detect timing deviations during demodulation of servo data in the short servo sector in a short servo device. If it is not a short servo device, i.e., if all servos are ordinary servos, append mode 1 and append mode 2 may not be required.

[0172] On the other hand, in the servo sector SVS1 of this embodiment, preamble 1, servo marker 1, Gray code 1, burst data 1, append mode 1, preamble 2, servo marker 2, Gray code 2, burst data 2, and append mode 2 are arranged sequentially in the travel direction d2. By reducing the gap GP, preamble 2 is configured adjacent to append mode 1. If it is not a short servo device, preamble 2 can also be configured adjacent to burst data 1.

[0173] Figure 14 This is a schematic diagram illustrating an example of front-side servo read processing in the dual-segment servo region ZB of the disk 10 according to this embodiment. Figure 14 The configuration details, such as servo mode and postcode, are shown. Additionally, in... Figure 14 The diagram shows a servo mode in which the suffix 1 of the segment servo sector ZSVS01 is configured after the pulse train data 2 when reading the front segment servo sector ZSVS01 in the dual segment servo region ZB with reduced gap GP (using the demodulated data of the front segment servo sector ZSVS01 for positioning of the head 15).

[0174] like Figure 14 As shown, suffix 1 is positioned after pulse train data 2, adjacent to it. Suffix 1 is overwritten in... Figure 13 The appended mode 2 is shown. The servo frequency of the suffix 1 is different from the servo frequency of the preceding preamble 2. The servo frequency of the preceding preamble 1 is the same as the servo frequency of the suffix 1.

[0175] In this embodiment, segment servo sector ZSVS01 is positioned on the outer periphery (OD) side compared to segment servo sector ZSVS11, and the servo frequency of segment servo sector ZSVS01 is higher than that of segment servo sector ZSVS11. For example, the servo frequency of segment servo sector ZSVS01 is 400MHz, and the servo frequency of segment servo sector ZSVS11 is 300MHz.

[0176] The servo strobe is asserted at time T31 corresponding to preamble 1 and negated at time T32 corresponding to postcode 1. This allows the reading of preamble 1, servo flag 1, Gray code 1, burst data 1, append mode 1, and postcode 1 from the preceding servo sector ZSVS01. By timing the preamble 1, servo flag 1, Gray code 1, burst data 1, append mode 1, and postcode 1 within the specified period when the servo strobe is in an asserted state, such as when the servo strobe is ON as a reference timing, appropriate servo data can be demodulated.

[0177] In addition, through such Figure 14 As shown, setting timer T31 midway through preamble 1 allows writing to continue until just before timer T31. On the other hand, no writing or reading occurs during the first 15 seek cycles; therefore, timer T31 can also be... Figure 14 The example is the timing on the front end of the preamble 1.

[0178] The RRO strobe used to read postfix 1 is asserted at timer T33 corresponding to the front end of postfix 1 and negated at timer T34 corresponding to the back end of postfix 1. Thus, postfix 1 can be read. Furthermore, timer T32 can be simultaneous with timer T34 or can be a timer following timer T34.

[0179] Figure 15 This is a schematic diagram illustrating an example of rear-side servo read processing in the dual-segment servo region ZB of the disk 10 according to this embodiment. Figure 15 The configuration details, such as servo mode and postcode, are shown. Additionally, in... Figure 15 The diagram shows a servo mode in which the suffix 2 of the segment servo sector ZSVS12 is configured after the pulse train data 2 when reading the rear segment servo sector ZSVS12 in the dual segment servo region ZB with reduced gap GP (using the demodulated data of the rear segment servo sector ZSVS12 for positioning of the head 15).

[0180] like Figure 15 As shown, the suffix 2 is positioned behind and adjacent to the pulse train data 2. The servo frequency of the suffix 2 is the same as the servo frequency of the preceding suffix 2.

[0181] The servo gating is asserted at time T41 corresponding to preamble 2 and negated at time T42 corresponding to postcode 2. Thus, the preamble 2, servo flag 2, Gray code 2, pulse train data 2, and postcode 2 of the subsequent servo sector ZSVS12 can be read.

[0182] The RRO strobe used to read suffix 2 is asserted at timer T43 corresponding to the front end of suffix 2, and negated at timer T44 corresponding to the back end of suffix 2. Thus, suffix 2 can be read. Furthermore, timer T42 can be simultaneous with timer T44, or it can be a timer following timer T44.

[0183] Figure 16 This is a schematic diagram illustrating an example of servo read processing in a single segment servo region ZG of disk 10 according to this embodiment. Figure 16 The configuration details, such as servo mode and postcode, are shown. Additionally, in... Figure 16 The diagram shows the servo mode in which the suffix 3 is configured after the pulse train data 3 when reading the servo mode of a single segment servo region (single segment servo region) ZG (using the demodulated data of the single segment servo region ZG for the positioning of the first 15).

[0184] like Figure 16 As shown, the preamble 3, servo marker 3, Gray code 3, pulse train data 3, and suffix 3 of a single-segment servo region ZG are arranged sequentially along the travel direction d2. The servo frequency of the suffix 3 is the same as that of the preamble 3.

[0185] The servo gating is asserted at time T51 corresponding to preamble 3 and negated at time T52 corresponding to postcode 3. Thus, preamble 3, servo flag 3, Gray code 3, pulse train data 3, and postcode 3 can be read.

[0186] The RRO strobe used to read suffix 3 is asserted at timer T53 corresponding to the front end of suffix 3, and negated at timer T54 corresponding to the back end of suffix 3. Thus, suffix 3 can be read. Furthermore, timer T52 can be simultaneous with timer T54, or it can be a timer following timer T54.

[0187] Next, a portion of disk 10 will be explained. Figure 17This is a schematic diagram showing a portion of the circumferential region in the disk 10 according to this embodiment, and it is a diagram showing one main servo region SVO and two data regions DTR. In the diagram, in the circumferential direction, multiple data segment regions DZ adjacent to the single segment servo region ZG are marked with dot patterns, and multiple data segment regions DZ adjacent to the dual segment servo region ZB are marked with diagonal lines pointing to the upper right. The dot patterns are marked more densely in the gap GP than in the data segment regions DZ.

[0188] like Figure 17 As shown, the main servo region SVO, which serves as the servo region SV, has multiple segmented servo regions, such as six segmented servo regions ZSV0, ZSV1, ZSV2, ZSV3, ZSV4, and ZSV5. Alternatively, the number of segmented servo regions can be more than six. Each segmented servo region ZSV0 to ZSV5 contains servo data other than the suffix code. Within the main servo region SVO, multiple single-segmented servo regions ZG and multiple dual-segmented servo regions ZB are arranged along the radial direction d1.

[0189] In each of the dual-segment servo regions ZB1, ZB2, ZB3, ZB4, and ZB5, the front segment servo region and the rear segment servo region are arranged sequentially and adjacent to each other in the travel direction d2. There is no gap (gap = 0) between the front and rear segment servo regions in each of the dual-segment servo regions ZB1 to ZB5. Therefore, in the disk device 1 according to this embodiment, the servo occupancy rate of the dual-segment servo region ZB can be reduced, and data format efficiency can be improved.

[0190] In a single servo region ZG, each suffix code region PC0_a, PC1_a, PC2_a, PC3_a, PC4_a, and PC5_a is located after and adjacent to its corresponding servo region ZSV. The suffix codes of each suffix code region PC0_a, PC1_a, PC2_a, PC3_a, PC4_a, and PC5_a are used to correct the position of the header 15 when demodulating the servo data of the corresponding servo region ZSV.

[0191] For example, in a single segment servo region ZG, the suffix code region PC0_a is located after and adjacent to segment servo region ZSV0. The suffix code of the suffix code region PC0_a is used to correct the position of the header 15 when demodulating the servo data of segment servo region ZSV0.

[0192] In the dual-segment servo region ZB, the suffix codes PC1_a, PC3_a, and PC5_a for the rear segment servo region ZSV are located behind and adjacent to their respective rear segment servo regions ZSV. The suffix codes of each suffix code region PC1_a, PC3_a, and PC5_a are used to correct the position of the header 15 when demodulating the servo data of the corresponding rear segment servo region ZSV.

[0193] For example, in a dual-segment servo region ZB, the postcode region PC1_a for segment servo region ZSV1 is located after segment servo region ZSV1 and adjacent to segment servo region ZSV1. The postcode of postcode region PC1_a is used to correct the position of head 15 when demodulating the servo data of segment servo region ZSV1.

[0194] In the dual-segment servo region ZB, the respective postcode regions PC0_4, PC2_10, PC2_15, PC4_20, and PC4_25 of the front segment servo region ZSV are located behind and adjacent to the rear segment servo region ZSV. For example, the respective postcode regions PC0_4, PC2_10, PC2_15, PC4_20, and PC4_25 are located behind and adjacent to the pulse train region of the rear segment servo region ZSV. The respective postcode regions PC0_4, PC2_10, PC2_15, PC4_20, and PC4_25 are used to correct the position of the head 15 when demodulating the servo data of the corresponding front segment servo region ZSV.

[0195] For example, in the region passing through data segment region DZ4 in the circumferential direction, the postcode region PC0_4 for segment servo region ZSV0 is configured behind segment servo region ZSV1 (e.g., the pulse train region of segment servo region ZSV1). In the region passing through data segment region DZ10 in the circumferential direction, the postcode region PC2_10 for segment servo region ZSV2 is configured behind segment servo region ZSV1 (e.g., the pulse train region of segment servo region ZSV1). In the region passing through data segment region DZ15 in the circumferential direction, the postcode region PC2_15 for segment servo region ZSV2 is configured behind segment servo region ZSV3 (e.g., the pulse train region of segment servo region ZSV3). In the region passing through data segment region DZ20 in the circumferential direction, the postcode region PC4_20 for segment servo region ZSV4 is configured behind segment servo region ZSV3 (e.g., the pulse train region of segment servo region ZSV3). In the area passing through the data segment area DZ25 in the circumferential direction, the postcode area PC4_25 for the segment servo area ZSV4 is configured behind the segment servo area ZSV5 (e.g., the pulse train area of ​​the segment servo area ZSV5).

[0196] The servo regions ZSV0, PC0_a, and PC0_4 share the same first servo frequency. The servo regions ZSV1 and PC1_a share the same second servo frequency. The servo regions ZSV2, PC2_a, PC2_10, and PC2_15 share the same third servo frequency. The servo regions ZSV3 and PC3_a share the same fourth servo frequency. The servo regions ZSV4, PC4_a, PC4_20, and PC4_25 share the same fourth servo frequency. The servo regions ZSV5 and PC5_a share the same sixth servo frequency.

[0197] The first servo frequency is higher than the second servo frequency. The second servo frequency is higher than the third servo frequency. The third servo frequency is higher than the fourth servo frequency. The fourth servo frequency is higher than the fifth servo frequency. The fifth servo frequency is higher than the sixth servo frequency.

[0198] Each data region DTR has multiple data segment regions DZ. Taking the data region DTR located behind the main servo region SVO in the rotation direction d3 as an example, the data region DTR has multiple data segment regions DZ from the data segment region DZ0 on the outer perimeter OD side to the data segment region DZ29 on the inner perimeter ID side.

[0199] Considering the area passing through the data segment region DZ3 in the circumferential direction, the data segment region DZ, the segment servo region ZSV0, the postcode region PC0_a, the gap GP (GP3) and the data segment region DZ3 are arranged sequentially in the travel direction d2.

[0200] Considering the area passing through the data segment region DZ4 in the circumferential direction, the data segment region DZ, the segment servo region ZSV0, the segment servo region ZSV1, the postcode region PC0_4, the gap GP (GP4) and the data segment region DZ4 are arranged sequentially in the travel direction d2.

[0201] Considering the area passing through the data segment region DZ9 in the circumferential direction, the data segment region DZ, the segment servo region ZSV2, the segment servo region ZSV1, the postcode region PC1_a, the gap GP (GP9) and the data segment region DZ9 are arranged sequentially in the travel direction d2.

[0202] Considering the area passing through the data segment region DZ11 in the circumferential direction, the data segment region DZ, the segment servo region ZSV2, the postcode region PC2_a, the gap GP (GP11), and the data segment region DZ11 are arranged sequentially in the travel direction d2.

[0203] Considering the area passing through the data segment region DZ14 in the circumferential direction, the data segment region DZ, the segment servo region ZSV2, the postcode region PC2_a, the gap GP (GP14) and the data segment region DZ14 are arranged sequentially in the travel direction d2.

[0204] Considering the area passing through the data segment region DZ15 in the circumferential direction, the data segment region DZ, the segment servo region ZSV2, the segment servo region ZSV3, the postcode region PC2_15, the gap GP (GP15), and the data segment region DZ15 are arranged sequentially in the travel direction d2.

[0205] Considering the area passing through the data segment region DZ19 in the circumferential direction, the data segment region DZ, the segment servo region ZSV4, the segment servo region ZSV3, the postcode region PC3_a, the gap GP (GP19), and the data segment region DZ19 are arranged sequentially in the travel direction d2.

[0206] Considering the area passing through the data segment region DZ21 in the circumferential direction, the data segment region DZ, the segment servo region ZSV4, the postcode region PC4_a, the gap GP (GP21) and the data segment region DZ21 are arranged sequentially in the travel direction d2.

[0207] Considering the area passing through the data segment region DZ24 in the circumferential direction, the data segment region DZ, the segment servo region ZSV4, the postcode region PC4_a, the gap GP (GP24), and the data segment region DZ24 are arranged sequentially in the travel direction d2.

[0208] Considering the area passing through the data segment region DZ25 in the circumferential direction, the data segment region DZ, the segment servo region ZSV4, the segment servo region ZSV5, the postcode region PC4_25, the gap GP (GP25), and the data segment region DZ25 are arranged sequentially in the travel direction d2.

[0209] As described above, by setting the gap GP, the position of the front end of the data segment region DZ (the starting position of the data region after the servo region passes) is offset, so as not to cause the erasure of the postcode of the adjacent postcode region PC in the radial direction d1.

[0210] The front end (data start position) of the data segment region DZ3 is offset from the rear end of the postcode region PC0_a by a circumferential length L3 of the gap GP3, so that the postcode of the postcode region PC0_4 is not erased from the outer periphery OD (data segment region DZ3).

[0211] The front end of the data segment region DZ4 is offset from the rear end of the postcode region PC0_4 by a circumferential length L4 of the gap GP4, so that the postcode of the postcode region PC1_a is not erased from the outer periphery OD (data segment region DZ4).

[0212] The front end of the data segment region DZ9 is offset from the rear end of the postcode region PC1_a by a circumferential length L9 of the gap GP9, so that the postcode of the postcode region PC2_10 is not erased from the outer periphery OD (data segment region DZ9).

[0213] The front end of the data segment region DZ11 is offset from the rear end of the postcode region PC2_a by a circumferential length L11 of the gap GP11, so that the postcode of the postcode region PC2_10 is not erased from the inner circumference ID (data segment region DZ11) side.

[0214] The front end of the data segment region DZ14 is offset from the rear end of the postcode region PC2_a by a circumferential length L14 of the gap GP14, so that the postcode of the postcode region PC2_15 is not erased from the outer periphery OD (data segment region DZ14).

[0215] The front end of the data segment region DZ15 is offset from the rear end of the postcode region PC2_15 by a circumferential length L15 of the gap GP15, so that the postcode of the postcode region PC3_a is not erased from the outer periphery OD (data segment region DZ15) side.

[0216] The front end of the data segment region DZ19 is offset from the rear end of the postcode region PC3_a by a circumferential length L19 of the gap GP19, so that the postcode of the postcode region PC4_20 is not erased from the outer periphery OD (data segment region DZ19).

[0217] The front end of the data segment region DZ21 is offset from the rear end of the postcode region PC4_a by a circumferential length L21 of the gap GP21, so that the postcode of the postcode region PC4_20 is not erased from the inner circumference ID (data segment region DZ21) side.

[0218] The front end of the data segment region DZ24 is offset from the rear end of the postcode region PC4_a by a circumferential length L24 of the gap GP24, so that the postcode of the postcode region PC4_25 is not erased from the outer periphery OD (data segment region DZ24).

[0219] The front end of the data segment region DZ25 is offset from the rear end of the postcode region PC4_25 by a circumferential length L25 of the gap GP25, so that the postcode of the postcode region PC5_a is not erased from the outer periphery OD (data segment region DZ25) side.

[0220] exist Figure 17 In the example shown, data segment regions DZ3 and DZ4 are set as different data segments, but the beginning of the data (the start position) of data segment regions DZ3 and DZ4 is essentially the same. Therefore, data segment regions DZ3 and DZ4 can also be processed as data segments with the same data format.

[0221] Focusing on data segments DZ3 to DZ5, the leading edge of data segment DZ4 is aligned with the leading edge of data segment DZ5 in the radial direction d1, but it can also be offset backward compared to the leading edge of data segment DZ5. The leading edge of data segment DZ3 can also be aligned with at least one of the leading edges of data segment DZ4 and data segment DZ5 in the radial direction d1, but it can be offset forward by a maximum length L4 compared to the leading edge of data segment DZ4. By offsetting the leading edge of data segment DZ3 forward compared to the leading edge of data segment DZ4, the formatting loss of the data segment can be improved.

[0222] Similarly, data segment regions DZ10 and DZ11 can be set as different data segments, but they can also be processed as data segments with the same data format.

[0223] Data segment regions DZ14 and DZ15 can be set as the same but different data segments, or they can be processed as data segments with the same data format.

[0224] Data segment regions DZ20 and DZ21 can be set as different data segments, but they can also be processed as data segments with the same data format.

[0225] Data segment regions DZ24 and DZ25 can be set as different data segments, but they can also be processed as data segments with the same data format.

[0226] Figure 18 This refers to a portion of the servo regions SV arranged in the circumferential direction of the disk 10 according to this embodiment, along the radial direction d1 (hereinafter referred to as...). Figure 18 The diagram, referred to in the description as servo, gap GP, and data segment region DZ, is an example of how servo strobe SG, write strobe WG, and read strobe RG can be shown together. Furthermore, in Figure 18 The diagram illustrates an example of servo strobes SG, write strobe WG, and read strobe RG used for traversing the data segment regions DZ3, DZ4, DZ9, DZ11, DZ14, DZ15, DZ19, DZ21, DZ24, and DZ25 in the circumferential direction. In the diagram, the data segment region DZ is not configured in the region marked with an upward-facing diagonal line in the gap GP. If a data segment region DZ were configured in the region marked with an upward-facing diagonal line, it would cause the erasure of the last code in the last code region adjacent to the region marked with the upward-facing diagonal line in the radial direction d1.

[0227] like Figure 18 As shown, timing T72 is set to offset the beginning of the data segment region DZ from the end of the servo by a gap GP. With the servo end timing, such as the servo strobe SG negation timing T71, as the reference, timing T72 is the timing after a predetermined delay period from timing T71, and is the timing for asserting the write strobe WG.

[0228] Timer T73 is set to read user data from the staggered data segment region DZ. With timer T71 as the reference, timer T73 is the timer that occurs after a predetermined delay period following timer T71, and is the timer for assertion by the read strobe RG.

[0229] For example, at time T72, after a delay period of WGdly2 following the negation of the servo strobe SG at time T71, an assertion is made on the write strobe WG. This allows user data to be written to the data segment region DZ without erasing the postcode of the postcode region adjacent to the gap GP in the radial direction d1. Furthermore, at time T73, after a delay period of RGdly2 following time T71, an assertion is made on the read strobe RG. This allows user data in the data segment region DZ that has been written out of order to be read.

[0230] Next, the format loss of the dual-segment servo region ZB will be explained. In the servo sector SVS of the dual-segment servo region ZB, the first servo with servo length S1, the gap with gap length G1, and the second servo with servo length S2 are arranged along the disk rotation direction d3. Here, the number of servo sector SVSs in a track is set to N, and the length occupied by the servo in a track is set to A. Thus, the length A is represented by the following formula.

[0231] A = N × (S1 + G1 + S2)

[0232] Furthermore, let LE be the length of one track, and let DI be the length that can be used as the data area DTR within a track. Thus, the length DI is represented by the following formula.

[0233] DI = LE - A = LE - N × (S1 + G1 + S2)

[0234] As in this embodiment, in the dual-segment servo region ZB, if the gap between the front segment servo region ZSV and the rear segment servo region ZSV becomes 0, then the length DI becomes the maximum value. That is, if the gap length G1 becomes 0, then the length DI that can be used as a data region DTR in a track can be maximized.

[0235] Next, an example will be given in which the gap between the front segment servo region ZSV and the rear segment servo region ZSV in the dual segment servo region ZB is reduced to 0, thereby improving the proportion of format loss. Figure 19 The graphs used in this embodiment and the comparative example above respectively show the change of the proportion of format loss relative to the radius position of disk 10.

[0236] like Figure 19As shown, in the comparative example above, there was a gap between the front segment servo area ZSV and the rear segment servo area ZSV. However, in this embodiment, the gap between the front segment servo area ZSV and the rear segment servo area ZSV is eliminated. In this embodiment, format loss is improved, and therefore, for example, the recording capacity of the disk device 1 can be increased.

[0237] Next, the method for writing the postcode in each region along the radial direction d1 will be explained.

[0238] When focusing on the region that passes through a single segment servo region ZG in the circumferential direction, the postcode can be written at a time after the period corresponding to the read / write gap Grw has passed from the end of the segment servo region ZSV (e.g., the pulse train region of the segment servo region ZSV).

[0239] For example in Figure 16 In this context, with the detection position (end position) of servo marker 3 as the reference, the timing for writing postcode 3 becomes the timing after the detection position of servo marker 3 has passed the sum of the length in the circumferential direction of Gray code 3, the length in the circumferential direction of pulse train data 3, and the read / write gap Grw in the circumferential direction.

[0240] When focusing on the region that is read from the rear segment servo sector ZSVS in the circumferential direction through the dual segment servo region ZB, the postcode is written after the period corresponding to the read / write gap Grw has passed from the rear end of the rear segment servo sector ZSVS (e.g., the pulse train region of the rear segment servo sector ZSVS).

[0241] For example in Figure 15 In this context, with the detection position (end position) of the servo mark 2 of the servo sector ZSVS on the rear side as the reference, the timing for writing the postcode 2 becomes the timing after the detection position of the servo mark 2 has passed the sum of the length in the circumferential direction of the Gray code 2, the length in the circumferential direction of the pulse train data 2, and the read / write gap Grw in the circumferential direction.

[0242] When focusing on the region that reads from the preceding segment servo sector ZSVS within the circumferential region of the dual segment servo region ZB, the postfix is ​​not written at a time after the period corresponding to the read / write gap Grw following the end of the preceding segment servo sector ZSVS (e.g., the pulse train region of the preceding segment servo sector ZSVS), but rather at a time after the period corresponding to the read / write gap Grw following the end of the following segment servo sector ZSVS (e.g., the pulse train region of the following segment servo sector ZSVS).

[0243] For example in Figure 14 In this context, with the detection position (end position) of the servo marker 1 in the preceding segment servo sector ZSVS as the reference, the timing for writing the postcode 1 becomes the timing after the detection position of the servo marker 1 has passed the time corresponding to the sum of the length in the circumferential direction of Gray code 1, the length in the circumferential direction of pulse train data 1, the length in the circumferential direction of append mode 1, the length in the circumferential direction of preamble 2, the length in the circumferential direction of servo marker 2, the length in the circumferential direction of Gray code 2, the length in the circumferential direction of pulse train data 2, and the read / write gap Grw in the circumferential direction.

[0244] When using the detection position (end position) of the servo mark of the read servo (servo of the segment servo sector ZSVS) as a reference, and reading the segment servo sector ZSVS of a single segment servo region ZG or the segment servo sector ZSVS behind a dual segment servo region ZB, the timing WtTiming1 for writing the postcode is as follows. That is, the timing WtTiming1 is set to the time corresponding to the sum of the length in the circumferential direction of the Gray code of the read servo, the length in the circumferential direction of the read servo pulse train data, and the read / write gap Grw in the circumferential direction from the detection position of the servo mark.

[0245] When using the detection position (end position) of the servo mark of the read servo (servo of the segment servo sector ZSVS) as a reference, and reading the segment servo sector ZSVS on the front side of the dual segment servo area ZB, the timing WtTiming2 for writing the postcode is as follows. That is, the timing WtTiming2 is set to the time corresponding to the sum of the length in the circumferential direction of the Gray code of the read servo, the length in the circumferential direction of the pulse train data of the read servo, the length in the circumferential direction of the append mode of the read servo, the length in the circumferential direction of the preamble of the servo that is not read (cannot be accurately demodulated), the length in the circumferential direction of the servo mark that is not read, the length in the circumferential direction of the Gray code that is not read, the length in the circumferential direction of the pulse train data that is not read, and the read / write gap Grw in the circumferential direction.

[0246] Next, the timing of reading the postcode in each region of the radius direction d1 will be explained.

[0247] When focusing on the region passing through a single segment servo region ZG in the circumferential direction, assert the RRO gating from the rear end of the segment servo sector ZSVS (e.g., the pulse train region of the segment servo sector ZSVS) and read the postcode.

[0248] For example in Figure 16 In this context, with the detection position (end position) of servo marker 3 as the reference, the timing for reading postcode 3 (the timing for asserting RRO strobe) becomes the timing after the detection position of servo marker 3 has elapsed for a period of time corresponding to the sum of the length in the circumferential direction of Gray code 3 and the length in the circumferential direction of pulse train data 3.

[0249] When focusing on the region of the dual segment servo region ZB in the circumferential direction, which is the region through which the subsequent segment servo sector ZSVS is read, the RRO gating is asserted from the rear end of the subsequent segment servo sector ZSVS (e.g., the pulse train region of the subsequent segment servo sector ZSVS), and the postcode is read.

[0250] For example in Figure 15 In this context, when the detection position (end position) of the servo mark 2 of the servo sector ZSVS on the rear side is used as a reference, the timing for reading the postcode 2 (the timing for asserting the RRO strobe) becomes the timing after the detection position of the servo mark 2 has passed the sum of the length in the circumferential direction of the Gray code 2 and the length in the circumferential direction of the pulse train data 2.

[0251] When focusing on the region in the circumferential direction that passes through the dual segment servo region ZB and reads the region of the preceding segment servo sector ZSVS, instead of reading the postcode from the rear end of the preceding segment servo sector ZSVS (e.g., the pulse train region of the preceding segment servo sector ZSVS), asserting the RRO strobe from the rear end of the following segment servo sector ZSVS (e.g., the pulse train region of the following segment servo sector ZSVS) and reading the postcode.

[0252] For example in Figure 14 In this context, with the detection position (end position) of the servo marker 1 in the preceding segment servo sector ZSVS as the reference, the timing for reading the postcode 1 (the timing for asserting the RRO strobe) becomes the timing after the detection position of the servo marker 1 has passed the sum of the lengths in the circumferential direction of Gray code 1, the circumferential direction of pulse train data 1, the circumferential direction of append mode 1, the circumferential direction of preamble 2, the circumferential direction of servo marker 2, the circumferential direction of Gray code 2, and the circumferential direction of pulse train data 2.

[0253] When using the detection position (end position) of the servo mark of the read servo (servo of segment servo sector ZSVS) as a reference, and reading the segment servo sector ZSVS of a single segment servo region ZG or the segment servo sector ZSVS behind a dual segment servo region ZB, the timing RdTiming1 for reading the postcode is as follows. That is, the timing RdTiming1 is set to a time corresponding to the sum of the length of the circumference of the Gray code of the read servo and the length of the circumference of the pulse train data of the read servo, starting from the detection position of the servo mark.

[0254] When using the detection position (end position) of the servo mark of the read servo (servo of the segment servo sector ZSVS) as a reference, and reading the segment servo sector ZSVS before the dual segment servo area ZB, the timing RdTiming2 for reading the postcode is as follows. That is, the timing RdTiming2 is set to the time corresponding to the sum of the length in the circumferential direction of the Gray code of the read servo, the length in the circumferential direction of the read servo pulse train data, the length in the circumferential direction of the read servo append mode, the length in the circumferential direction of the preamble of the unread servo, the length in the circumferential direction of the unread servo mark, the length in the circumferential direction of the unread Gray code, and the length in the circumferential direction of the unread pulse train data, starting from the detection position of the servo mark.

[0255] Figure 20 This is a flowchart illustrating an example of a postcode writing method according to this embodiment.

[0256] like Figure 8 and Figure 20 As shown, when the write processing of the postcode begins, firstly, in step STa1, the system controller 130 determines whether to use the preceding segment servo sector ZSVS when writing the postcode.

[0257] like Figure 8 , Figure 15 as well as Figure 20 As shown, when the system controller 130 determines that the front-side segment servo sector ZSVS is not used (step STa1), it proceeds to step STa2. In step STa2, the system controller 130 selects timing WtTiming1 and selects postcode 2. Then, it proceeds to step STa4. In step STa4, the selected postcode (postcode 2) is written to a predetermined area of ​​disk 10, and the postcode writing process is completed.

[0258] like Figure 8 , Figure 14 as well as Figure 20 As shown, on the other hand, if the system controller 130 determines that the front-side segment servo sector ZSVS is to be used (step STa1), the process proceeds to step STa3. In step STa3, the system controller 130 selects timing WtTiming2 and selects postcode 1. Then, the process proceeds to step STa4. In step STa4, the selected postcode (postcode 1) is written to a predetermined area of ​​disk 10, and the postcode writing process is completed.

[0259] Figure 21 This is a flowchart illustrating an example of a postcode reading processing method according to this embodiment.

[0260] like Figure 8 and Figure 21 As shown, when the reading process of the postcode begins, firstly, in step STb1, the system controller 130 determines whether to use the preceding segment servo sector ZSVS when reading the postcode.

[0261] like Figure 8 , Figure 15 as well as Figure 21 As shown, when the system controller 130 determines that the front-side segment servo sector ZSVS is not used (step STb1), the process proceeds to step STb2. In step STb2, the system controller 130 selects timing RdTiming1 and selects postcode 2. Then, the process proceeds to step STb4. In step STb4, the selected postcode (postcode 2) is read, and the postcode reading process is completed.

[0262] like Figure 8 , Figure 14 as well as Figure 21 As shown, on the other hand, if the system controller 130 determines that the front-side segment servo sector ZSVS is to be used (step STb1), the process proceeds to step STb3. In step STb3, the system controller 130 selects timing RdTiming2 and selects postcode 1. Then, the process proceeds to step STb4. In step STb4, the selected postcode (postcode 1) is read, and the postcode reading process is completed.

[0263] Next, use Figure 1 and Figure 22 The configuration and effects of the disk device 1 according to this embodiment will be explained. Figure 22 This is a schematic diagram showing a portion of the circumferential region in disk 1 according to this embodiment, and a diagram showing one servo region SV and two data regions DTR. In the diagram, the dot pattern is marked more densely in the non-object region NRO than in the second object region RO2.

[0264] like Figure 1 and Figure 22 As shown, the disk device 1 according to the first embodiment configured as described above includes a disk 10, a head 15, and a controller 130.

[0265] (1) Disk 10 has a dual segment servo region (segment servo boundary region) ZBa in the servo region SV, which includes a first region (first segment servo region) RE1 with a first servo frequency, a second region (second segment servo region) RE2 with a second servo frequency, and a third region (first correction data storage region) RE3 with the first servo frequency. Head 15 has a write head 15W for writing data to disk 10 and a read head 15R for reading data from disk 10. In order to position head 15 in association with a predetermined track, controller 130 demodulates the first servo data of the first region RE1 read by head 15 to derive the position of head 15, and demodulates the first correction data of the third region RE3 read by head 15 to correct the position of head 15.

[0266] A first region RE1, a second region RE2, and a third region RE3 are arranged sequentially in the traveling direction d2 of the head 15 relative to the disk 10. The first region RE1 and the second region RE2 are adjacent to each other in the circumferential direction of the disk 10. The second region RE2 and the third region RE3 are also adjacent to each other in the circumferential direction of the disk 10. There is no gap between the first region RE1 and the second region RE2. Therefore, in the disk device 1 according to this first embodiment, the server occupancy rate can be reduced, and data format efficiency can be improved.

[0267] For example, region RE1 is the front segment servo region ZSV, region RE2 is the rear segment servo region ZSV, and region RE3 contains the first postcode region. The first segment servo sector ZSVS1 in region RE1 includes the first preamble region, the first servo marker region, the first Gray code region, and the first pulse train region, arranged sequentially in the direction of travel d2. Figure 14 The second servo sector ZSVS2 in region RE2 includes the second preamble region, the second servo marker region, the second Gray code region, and the second burst region arranged sequentially in the direction of travel d2. Figure 14 The first servo frequency is the same as the frequency of the first preamble region. The second servo frequency is the same as the frequency of the second preamble region.

[0268] (2) In addition, the dual-segment servo region (segment servo boundary region) ZBa also includes the fourth region (second correction data storage region) RE4 of the second servo frequency mentioned above. In order to position the head 15 in association with a predetermined track, the controller 130 demodulates the second servo data of the second region RE2 read by the head 15 to derive the position of the head 15, and demodulates the second correction data of the fourth region RE4 read by the head 15 to correct the position of the head 15. The first region RE1, the second region RE2 and the fourth region RE4 are arranged sequentially in the travel direction d2. The second region RE2 and the fourth region RE4 are adjacent to each other in the circumferential direction of the disk 10.

[0269] Region 3 (RE3) and Region 4 (RE4) are adjacent to each other in the radial direction d1 of disk 10. In other words, by configuring Region 3 (RE3) to be adjacent to Region 4 (RE4) in the radial direction d1, the gap between Region 1 (RE1) and Region 2 (RE2) can be reduced.

[0270] For example, region 1 RE1 is the front segment servo region ZSV, region 2 RE2 is the rear segment servo region ZSV, region 3 RE3 contains the first postcode region, and region 4 RE4 contains the second postcode region. The third segment servo sector ZSVS3 in region 1 RE1 includes the first preamble region, the first servo marker region, the first Gray code region, and the first pulse train region arranged sequentially in the direction of travel d2. Figure 14 The fourth servo sector ZSVS4 in region RE2 includes the second preamble region, the second servo marker region, the second Gray code region, and the second burst region arranged sequentially in the direction of travel d2. Figure 14 The first servo frequency mentioned above is the same as the frequency of the first preamble region. The second servo frequency mentioned above is the same as the frequency of the second preamble region.

[0271] (3) Disk 10 also has a user data area (data area) DTR that is adjacent to the servo area SV in the travel direction d2. The first data sector DSC1 in the user data area DTR contains the first non-object area NRO1 and the first object area RO1 arranged sequentially in the travel direction d2. The first non-object area NRO1 is located between the third area RE3 (the second segment servo sector ZSVS2) and the first object area RO1 in the travel direction d2, and is adjacent to the third area RE3 and the first object area RO1 respectively.

[0272] The controller 130 treats the first object region RO1 as the object to be read and written, and excludes the first non-object region NRO1 from the objects to be read and written. For example, the first non-object region NRO1 is a gap GP ( Figure 18By setting the first non-object region NRO1 in the first data sector DSC1, the following situation can be avoided: when user data is written to the first object region RO1, the second postfix of the fourth region RE4 is erased.

[0273] Region 3 (RE3) is adjacent to region 4 (RE4) on its outer periphery. When the disk 10 is viewed with rotation direction d3 as a reference, the front end (front end) of the first target region (RO1) is aligned with the rear end (rear end) of region 4 (RE4) in the radial direction d1. This effectively prevents the second postcode of region 4 (RE4) from being erased.

[0274] In addition, with Figure 22 Unlike other examples, the front end of the first object region RO1 can also be located further back than the back end of the fourth region RE4. In other words, the front end of the first object region RO1 can also be located further forward of the back end of the fourth region RE4 in the direction of travel d2. In this case, it is also possible to effectively avoid the situation where the second postfix of the fourth region RE4 is erased.

[0275] (4) In addition, the servo region SV also includes the fifth region (third correction data storage region) RE5 of the first servo frequency mentioned above. To position the head 15 in association with a predetermined track, the controller 130 demodulates the first servo data read from the first region RE1 by the head 15 to derive the position of the head 15, and demodulates the third correction data read from the fifth region RE5 by the head 15 to correct the position of the head 15. The first region RE1 and the fifth region RE5 are arranged sequentially in the travel direction d2. The first region RE1 and the fifth region RE5 are adjacent to each other in the circumferential direction of the disk 10. The second region RE2 and the fifth region RE5 are adjacent to each other in the radial direction d1.

[0276] For example, region RE1 is the region located in the single-segment servo region ZG within the preceding segment servo region ZSV, and region RE5 contains the third postcode region. The fifth segment servo sector ZSVS5 within region RE1 contains the first preamble region, the first servo marker region, the first Gray code region, and the first pulse train region, arranged sequentially in the direction of travel d2. Figure 14 ).

[0277] (5) The third data sector DSC3 in the user data area DTR contains the third non-object area NRO3 and the third object area RO3 arranged sequentially in the travel direction d2. The third non-object area NRO3 is located between the fifth area RE5 (the fifth segment servo sector ZSVS5) and the third object area RO3 in the travel direction d2, and is adjacent to the fifth area RE5 and the third object area RO3 respectively.

[0278] The controller 130 treats the third object region RO3 as the object to be read and written, and excludes the third non-object region NRO3 from the objects to be read and written. For example, the third non-object region NRO3 is the gap GP ( Figure 18 By setting the third non-object region NRO3 in the third data sector DSC3, the following situation can be avoided: when user data is written to the third object region RO3, the first postfix of the third region RE3 is erased.

[0279] When disk 10 is viewed with rotation direction d3 as a reference, the front end of the third object region RO3 is aligned with the rear end of the third region RE3 in the radial direction d1. This effectively prevents the first postfix of the third region RE3 from being erased.

[0280] In addition, with Figure 22 Unlike other examples, the front end of the third object region RO3 can also be located further back than the back end of the third region RE3. In other words, the front end of the third object region RO3 can also be located further forward of the travel direction d2 than the back end of the third region RE3. In this case, it is also possible to effectively avoid the situation where the first postfix of the third region RE3 is erased.

[0281] Next, use Figure 1 and Figure 17 The configuration and effects of the disk device 1 according to this embodiment will be explained. Here, we focus on the dual segment servo region (segment servo boundary region) ZB2. Let: segment servo region ZSV2 correspond to the first region, segment servo region ZSV1 correspond to the second region, postcode region PC2_10 correspond to the third region, and postcode region PC1_a correspond to the fourth region.

[0282] like Figure 1 and Figure 17 As shown, the data segment region DZ9 of the user data region DTR includes the second non-object region NRO2 (gap GP9) and the second object region RO2, which are arranged sequentially in the direction of travel d2. The second non-object region NRO2 is located between the postcode region PC1_a (the fourth region) and the second object region RO2 in the direction of travel d2, and is adjacent to the postcode region PC1_a and the second object region RO2 respectively.

[0283] The controller 130 uses the second object region RO2 as the object to be read and written, and excludes the second non-object region NRO2 from the objects to be read and written. By setting the second non-object region NRO2 (gap GP9), it is possible to avoid the situation where the postcode of the postcode region PC2_10 is erased when user data is written to the second object region RO2.

[0284] The rear code region PC2_10 (region 3) is adjacent to the rear code region PC1_a (region 4) on its inner circumference. When the disk 10 is viewed with the rotation direction d3 as a reference, the front end (front end) of the second object region RO2 is aligned with the rear end (rear end) of the rear code region PC2_10 in the radial direction d1. This effectively prevents the rear code of the rear code region PC2_10 from being erased.

[0285] In addition, with Figure 17 Unlike other examples, the front end of the second object region RO2 can also be located further back than the rear end of the postcode region PC2_10. In other words, the front side of the second object region RO2 can also be located ahead of the rear end of the postcode region PC2_10 in the direction of travel d2. In this case, it is also possible to effectively avoid the situation where the postcode of the postcode region PC2_10 is erased.

[0286] (Second Implementation)

[0287] Next, the second embodiment will be described. The disk device 1 is configured in the same way as the first embodiment, except for the configuration described in this embodiment. Figure 23 This is a schematic diagram showing a portion of the circumferential region of the disk 10 in the disk device 1 according to this embodiment, and it shows a main servo region SVO and two data regions DTR. In the diagram, in the circumferential direction, multiple data segment regions DZ adjacent to the single-segment servo region ZG are marked with dotted patterns, and multiple data segment regions DZ adjacent to the dual-segment servo region ZB are marked with diagonal lines pointing to the upper right. However, the track skipping area TS in the data segment region DZ is colored white (blank).

[0288] like Figure 23 As shown, the data area DTR does not have a gap GP (non-object area NRO) adjacent to the servo area SV. This embodiment differs from the first embodiment described above in this respect. Figure 17This implementation differs from the previous one. In other words, to avoid the erasure of the postcode in the postcode region adjacent to the dual-segment servo region ZB in the circumferential direction, this embodiment does not employ a data format that offsets the front end of the data segment region DZ (data sector DSC) backward in the rotation direction d3. In this embodiment, the region in the data segment region DZ adjacent to the postcode region in the radial direction d1 is designated as the track skip region TS. By setting the track skip region TS in the data segment region DZ where user data is not written, the erasure of the postcode in the postcode region adjacent to the track skip region TS in the radial direction d1 can be avoided.

[0289] For example, the range adjacent to the data sector DSC that has been written in the radial direction d1 is defined as the data track range (track range). The data track range is the range that would cause an unwanted erase when user data is written to the data sector DSC. Here, the data track range is defined as wATE[track].

[0290] In the data segment regions DZ3, DZ4, DZ9, DZ14, DZ15, DZ19, DZ24, and DZ25, which may cause unwanted erasure on the inner peripheral ID side, a track skipping region TS is set on the inner peripheral ID side. In each data segment region DZ, at least the tracks from "the innermost track of the data segment region DZ - wATE+1 track" to "the innermost track of the data segment region DZ" are set as track skipping.

[0291] On the other hand, in data segment regions DZ11 and DZ21 that may cause unwanted erasure on the outer OD side, a track skipping region TS is set on the outer OD side. In each data segment region DZ, at least the "outermost track of the data segment region DZ" to the "track obtained by using the outermost track of the data segment region DZ + wATE-1 track" are set as track skipping. In addition, a count of 1 track towards the inner OD side is set as +1 track, and a count of 1 track towards the outer OD side is set as -1 track.

[0292] As described above, if a track skipping region TS is set in the data region DTR, then it is not necessary to set the first embodiment described above in the data region DTR. Figure 17 The gap GP shown Figure 22 The non-object region NRO is shown. However, it is important to note the upper limit on the number of tracks in the track skipping region TS, and this upper limit needs to be limited by the reduction... Figure 17 The gap GP causes the ADC (area density capability) gain within the range.

[0293] Next, use Figure 1 and Figure 24 The configuration and effects of the disk device 1 according to this embodiment will be explained. Figure 24 This is a schematic diagram showing a portion of the circumferential region in disk 1 according to this embodiment, and a diagram showing a servo region SV and two data regions DTR. Figure 24 This is a schematic diagram showing a portion of the circumferential region in disk 1 according to this embodiment, and a diagram showing one servo region SV and two data regions DTR. In the diagram, the non-object region NRO is set to white (blank).

[0294] like Figure 1 and Figure 24 As shown, the disk drive 1 according to the second embodiment configured as described above includes a disk 10, a head 15, and a controller 130. In this embodiment, there is no gap between the first region RE1 and the second region RE2. Therefore, this embodiment can achieve the same effects as the first embodiment described above.

[0295] Along the travel direction d2, the data segment region DZ, the first segment region ZSVR1 of the first region RE1 (segment servo region ZSV), the second segment region ZSVR2 of the second region RE2 (segment servo region ZSV), the third region RE3, and the first data segment region DZa are arranged sequentially. Along the travel direction d2, the data segment region DZ, the third segment region ZSVR3 of the first region RE1 (segment servo region ZSV), the fourth segment region ZSVR4 of the second region RE2 (segment servo region ZSV), the fourth region RE4, and the data segment region DZ are arranged sequentially. Along the travel direction d2, the data segment region DZ, the fifth segment region ZSVR5 of the first region RE1 (segment servo region ZSV), the fifth region RE5, and the second data segment region DZb are arranged sequentially.

[0296] (1) Disk 10 has a user data area (data area) DTR that is adjacent to the servo area SV in the travel direction d2. The first data segment area DZa in the user data area DTR includes a first non-object area NRO1 and a first object area RO1 that are adjacent to the third area (first correction data storage area) RE3 in the travel direction d2 and arranged in the radial direction d1. The first non-object area NRO1 is located between the fourth area (second correction data storage area) RE4 and the first object area RO1 in the radial direction d1, and is adjacent to the fourth area RE4 and the first object area RO1 respectively.

[0297] The controller 130 treats the first target region RO1 as the object of reading and writing, and excludes the first non-target region NRO1 from the objects of reading and writing. For example, the first non-target region NRO1 is the track skip region TS. Figure 23 The first object region RO1 is a non-track skip region. By setting the first non-object region NRO1 in the first data segment region DZa, the following situation can be avoided: when user data is written to the first object region RO1, the second postfix of the fourth region RE4 is erased.

[0298] In addition, the first non-object region NRO1 is the region that will be affected when user data (data) is written to the first object region RO1.

[0299] (2) In addition, the servo region SV includes the fifth region (third correction data storage region) RE5 of the first servo frequency mentioned above. In order to position the head 15 in association with a predetermined track, the controller 130 demodulates the first data of the first region RE1 read by the head 15 to derive the position of the head 15, and demodulates the fifth data of the fifth region RE5 read by the head 15 to correct the position of the head 15.

[0300] Region 1 (RE1) and Region 5 (RE5) are arranged sequentially in the direction of travel (d2). Region 1 (RE1) and Region 5 (RE5) are adjacent to each other in the circumferential direction of disk 10. Region 2 (RE2) and Region 5 (RE5) are adjacent to each other in the radial direction (d1).

[0301] For example, region RE1 is the region located in the single segment servo region ZG within the preceding segment servo region ZSV, and region RE5 contains the first postcode region. The fifth segment region ZSVR5 within region RE1 contains the first preamble region, the first servo marker region, the first Gray code region, and the first pulse train region, arranged sequentially in the travel direction d2. Figure 14 In addition, each of the first segment regions ZSVR1 to the fourth segment region ZSVR4 also includes the preamble region, servo marker region, Gray code region and pulse train region arranged sequentially in the direction of travel d2.

[0302] (3) The third data segment region DZc in the user data region DTR includes the third non-object region NRO3 and the third object region RO3, which are adjacent to the fifth region RE5 in the travel direction d2 and arranged in the radial direction d1. The third non-object region NRO2 is located between the second region RE2 and the third region RE3 and the third object region RO3 in the radial direction d1, and is adjacent to the second region RE2 (second segment region ZSVR2), the third region RE3 and the third object region RO3, respectively.

[0303] The controller 130 treats the third target region RO3 as the object to be read and written, and excludes the third non-target region NRO3 from the objects to be read and written. For example, the third non-target region NRO3 is a track skip region TS ( Figure 23 The third object region RO3 is a non-track skip region. By setting the third non-object region NRO3 in the third data segment region DZc, the following situation can be avoided: when user data is written to the third object region RO3, the first postfix of the third region RE3 is erased. In addition, the situation where the servo data in the second segment region ZSVR2 is erased can be avoided.

[0304] In addition, the third non-object region NRO3 is the region that will be affected when user data (data) is written to the third object region RO3.

[0305] Next, use Figure 1 and Figure 23 The configuration and effects of the disk device 1 according to this embodiment will be explained. Here, we focus on the dual segment servo region (segment servo boundary region) ZB2. Let: segment servo region ZSV2 correspond to the first region, segment servo region ZSV1 correspond to the second region, postcode region PC2_10 correspond to the third region, and postcode region PC1_a correspond to the fourth region.

[0306] like Figure 1 and Figure 23 As shown, the data segment region DZ9 of the user data region DTR includes a second non-object region NRO2 and a second object region RO2, which are adjacent to the postcode region PC1_a in the travel direction d2 and arranged in the radial direction d1. For example, the second non-object region NRO2 is a track skip region TS, and the second object region RO2 is a non-track skip region. The second non-object region NRO2 is located between the postcode region PC2_10 and the second object region RO2 in the radial direction d1, and is adjacent to both the postcode region PC2_10 and the second object region RO2.

[0307] The controller 130 uses the second object region RO2 as the object to be read and written, and excludes the second non-object region NRO2 from the objects to be read and written. By setting the second non-object region NRO2, the following situation can be avoided: when user data is written to the second object region RO2, the suffix of the suffix region PC2_10 is erased.

[0308] In addition, the second non-object region NRO2 is the region that will be affected when user data (data) is written to the second object region RO2.

[0309] Several embodiments of the present invention have been described above, but these embodiments are merely illustrative and not intended to limit the scope of the invention. These new embodiments can be implemented in a wide variety of other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and / or variations thereof are included within the scope and spirit of the invention, and are included within the scope of the invention as described in the claims and its equivalents.

Claims

1. A disk drive, comprising: The disk has a segmented servo boundary region in the servo region that includes a first region with a first servo frequency, a second region with a second servo frequency, and a third region with the first servo frequency. A head having a write head for writing data to the disk and a read head for reading data from the disk; and The controller, in order to position the head in association with a predetermined track, demodulates first servo data read by the head in the first region to derive the head's position, and demodulates first correction data read by the head in the third region to correct the head's position. The first region, the second region, and the third region are arranged sequentially in the direction of travel of the head relative to the disk. The first region and the second region are adjacent to each other in the circumferential direction of the disk. The second region and the third region are adjacent to each other in the circumferential direction of the disk.

2. The disk drive according to claim 1, The first region includes a first preamble region, a first servo marker region, a first Gray code region, and a first pulse train region arranged sequentially in the direction of travel of the head. The second region includes a second preamble region, a second servo marker region, a second Gray code region, and a second pulse train region arranged sequentially in the direction of travel of the head. The third region includes the first postcode region. The first servo frequency is the same as the frequency of the first preamble region. The second servo frequency is the same as the frequency of the second preamble region.

3. The disk drive according to claim 1, The segment servo boundary region also includes the fourth region of the second servo frequency. In order to position the head in association with a predetermined track, the controller demodulates the second servo data read by the head in the second region to derive the head's position, and demodulates the second correction data read by the head in the fourth region to correct the head's position. The first region, the second region, and the fourth region are arranged sequentially in the direction of travel of the head. The second region and the fourth region are adjacent to each other in the circumferential direction of the disk. The third region and the fourth region are adjacent to each other in the radial direction of the disk.

4. The disk drive according to claim 3, The first region includes a first preamble region, a first servo marker region, a first Gray code region, and a first pulse train region arranged sequentially in the direction of travel of the head. The second region includes a second preamble region, a second servo marker region, a second Gray code region, and a second pulse train region arranged sequentially in the direction of travel of the head. The third region includes the first postcode region. The fourth region includes the second postcode region. The first servo frequency is the same as the frequency of the first preamble region, and the second servo frequency is the same as the frequency of the second preamble region.

5. The disk drive according to claim 3, The disk also has a user data area adjacent to the servo area in the direction of travel of the head. The user data area comprises a first non-object area and a first object area arranged sequentially in the direction of travel of the head. The first non-object region is located between the third region and the first object region in the direction of travel of the head, and is adjacent to both the third region and the first object region. The controller treats the first object region as the object to be read and the object to be written, and excludes the first non-object region from the objects to be read and the objects to be written.

6. The disk drive according to claim 5, The third region and the fourth region are adjacent on the outer periphery. When the disk is observed with the direction of rotation of the disk, which is opposite to the direction of travel of the head, as the rotation direction and with the rotation direction as the reference, The front end of the first object region is aligned with the rear end of the fourth region in the radial direction, or... The front end of the first object region is located further back than the rear end of the fourth region.

7. The disk drive according to claim 3, The disk also has a user data area adjacent to the servo area in the direction of travel of the head. The user data area comprises a second non-object area and a second object area arranged sequentially in the direction of travel of the head. The second non-object region is located between the fourth region and the second object region in the direction of travel of the head, and is adjacent to both the fourth region and the second object region. The controller treats the second object region as the object to be read and the object to be written, and excludes the second non-object region from the object to be read and the object to be written.

8. The disk drive according to claim 7, The third region and the fourth region are adjacent on the inner periphery side. When the disk is observed with the direction of rotation of the disk, which is opposite to the direction of travel of the head, as the rotation direction and with the rotation direction as the reference, The front end of the second object region is aligned with the rear end of the third region in the radial direction, or... The front end of the second object region is located further back than the rear end of the third object region.

9. The disk drive according to claim 3, The servo region also includes the fifth region of the first servo frequency. In order to position the head in association with a predetermined magnetic track, the controller demodulates the first servo data read by the head in the first region to derive the head's position, and demodulates the third correction data read by the head in the fifth region to correct the head's position. The first region and the fifth region are arranged sequentially in the direction of travel of the head. The first region and the fifth region are adjacent to each other in the circumferential direction of the disk. The second region and the fifth region are adjacent to each other in the radial direction.

10. The disk drive according to claim 9, The disk also has a user data area adjacent to the servo area in the direction of travel of the head. The user data area comprises a third non-object area and a third object area arranged sequentially in the direction of travel of the head. The third non-object region is located between the fifth region and the third object region in the direction of travel of the head, and is adjacent to both the fifth region and the third object region. The controller treats the third object region as both the object to be read and the object to be written, and excludes the third non-object region from both the object to be read and the object to be written.

11. The disk drive according to claim 10, When the disk is observed with the direction of rotation opposite to the direction of travel of the head as the rotation direction and with the rotation direction as the reference, The front end of the third object region is aligned with the rear end of the third region in the radial direction, or... The front end of the third object region is located further back than the rear end of the third object region.

12. The disk drive according to claim 3, The disk also has a user data area adjacent to the servo area in the direction of travel of the head. The user data region includes a first non-object region and a first object region that are adjacent to the third region in the direction of travel of the head and arranged in the radial direction. The first non-object region is located between the fourth region and the first object region in the radial direction, and is adjacent to both the fourth region and the first object region. The controller treats the first object region as the object to be read and the object to be written, and excludes the first non-object region from the objects to be read and the objects to be written.

13. The disk drive according to claim 12, The first non-object region is the region that will be affected when the data is written to the first object region.

14. The disk drive according to claim 3, The disk also has a user data area adjacent to the servo area in the direction of travel of the head. The user data region includes a second non-object region and a second object region that are adjacent to the fourth region in the direction of travel of the head and arranged in the radial direction. The second non-object region is located between the third region and the second object region in the radial direction, and is adjacent to both the third region and the second object region. The controller treats the second object region as the object to be read and the object to be written, and excludes the second non-object region from the object to be read and the object to be written.

15. The disk drive according to claim 14, The second non-object region is the region that will be affected when the data is written to the second object region.

16. The disk drive according to claim 9, The disk also has a user data area adjacent to the servo area in the direction of travel of the head. The user data region includes a third non-object region and a third object region that are adjacent to the fifth region in the direction of travel of the head and arranged in the radial direction. The third non-object region is located in the radial direction between the second region and the third region and the third object region, and is adjacent to the second region, the third region and the third object region, respectively. The controller treats the third object region as both the object to be read and the object to be written, and excludes the third non-object region from both the object to be read and the object to be written.

17. The disk drive according to claim 16, The third non-object region is the region that will be affected when the data is written to the third object region.

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