Aligned shingle-shaped overlapping writing for magnetic recording media and media with positioned tracks featuring shingle-shaped overlapping edges

Abstract

A process that exhibits: Gathering information about how an arrangement of writing devices writes and is intended to write when recording shingled, overlapping tracks onto a magnetic data carrier; and Using the collected information, calculate data that describes a lateral writing position for use when writing, so that edges of shingle-like overlapping tracks are aligned according to a format, wherein the information is acquired by writing data onto a magnetic recording medium using writing devices of the arrangement, reading data at different lateral read positions relative to tracks containing the written data, and analyzing the data read at the different lateral read positions, and where the data is read by a different drive than a drive with the arrangement of write devices.

Description

BACKGROUND

[0001] The present invention relates to data storage systems and relates in particular to the edge placement of written data in order to achieve aligned shingle-shaped overlapping writing.

[0002] In magnetic storage systems, magnetic transducers read data from and write data to magnetic recording media. Data is written to the magnetic recording media by moving a magnetic recording transducer to a position above the media where the data is to be stored. The magnetic recording transducer then generates a magnetic field that encodes the data into the magnetic media. Data is read from the media by positioning the magnetic read transducer in a similar manner and then reading the magnetic field of the magnetic media. Read and write operations can be independently synchronized with the movement of the media to ensure that the data can be read from and written to the desired location on the media.

[0003] A key and ongoing goal in the data storage industry is to increase the density of data stored on a storage medium. In tape storage systems, this goal has led to increasing the track and linear bit density on the recording tape and reducing the thickness of the magnetic tape storage medium. The development of high-performance tape drive systems with a compact size has presented numerous challenges in the design of a tape head assembly for use in such systems.

[0004] In a tape drive system, the drive moves the magnetic tape at high speed across the surface of the tape head. The tape head is typically designed to minimize the distance between the head and the tape. The distance between the magnetic head and the magnetic tape is crucial, and therefore the objectives of these systems are to ensure that the recording slots of the transducers, which are the source of the magnetic recording flux, are in close contact with the tape to produce sharp write transitions, and that the read elements are also in close contact with the tape to ensure effective coupling of the magnetic field from the tape to the read elements.

[0005] The amount of data that can be stored on a magnetic tape can be increased by increasing the number of data tracks perpendicular to the tape direction. Furthermore, improvements in data storage capacity can be achieved through overlapping sections of data tracks (for example, shingled overlapping of data tracks).

[0006] A number of well-known documents address technically related topics: Document US 2014 / 0036383A1 describes a method for writing data to a tape storage medium, which includes writing first user data to a first physical region of the tape storage medium and writing second user data to a second physical region of the tape storage medium.

[0007] Document US 7 253 988 B2 describes a recording / playback method for a magnetic tape in a tracking servo system in which the recording density of each of the tracks is increased while simultaneously reducing recording / playback errors caused by a variable width of a magnetic tape.

[0008] Document US 7,116,514 B2 describes methods and systems for determining the position of a recording head, whereby existing data structures on the storage medium are provided. Knowing the distance ratio between a write and read element, at least a portion of a reference track is captured by the read element.

[0009] Despite the progress already made, there is still a need to further increase the recording density on magnetic tapes. SUMMARY

[0010] This task is solved by the subject matter of the independent patent claims. Further details are provided in the dependent patent claims.

[0011] A method according to one embodiment includes acquiring information on how an arrangement of writing devices writes and / or should write on a magnetic medium when recording in a shingled, overlapping manner, and using the acquired information, calculating data describing a lateral writing position for use during writing, such that shingled, overlapping track edges are aligned according to a format.

[0012] A method according to a further embodiment includes obtaining a lateral offset from a nominal writing position and applying the lateral offset to reposition a writing position of an arrangement of writing devices relative to a nominal writing position when writing in a first direction.

[0013] A product according to one embodiment includes a magnetic recording medium; and data indicating whether a lateral offset of the writing position was used during writing.

[0014] A computer program product according to one embodiment includes a computer-readable storage medium containing program instructions embodied therein, wherein the program instructions can be executed by a control unit to cause the control unit to execute one or more of the preceding methods.

[0015] Each of these embodiments can be implemented in a magnetic data storage system, for example a tape drive system comprising a magnetic head, a drive mechanism for guiding a magnetic medium (e.g. recording tape) over the magnetic head, and a control unit electrically connected to the magnetic head.

[0016] Further aspects and embodiments of the present invention will become clear from the following detailed description, which, in conjunction with the drawings, illustrates the basic ideas of the invention by way of example. BRIEF DESCRIPTION OF THE MULTIPLE DRAWING VIEWS Fig. Figure 1A is a schematic diagram of a simplified tape drive system according to one embodiment. Fig. Figure 1B is a schematic diagram of a tape cassette according to one embodiment. Fig. Figure 2 illustrates a side view of a freshly lapped, bidirectional magnetic tape head with two modules according to one embodiment. Fig. 2A is a view of a belt contact surface, viewed from line 2A of Fig. 2. Fig. 2B is a more detailed view, as seen from circle 2B of Fig. 2A. Fig. 2C is a more detailed partial view of a belt contact surface of a module pair. Fig. Figure 3 is a partial view of a tape contact surface of a magnetic head with a write-read-write configuration. Fig. Figure 4 is a partial view of a tape contact surface of a magnetic head with a read-write-read configuration. Fig. Figure 5 is a side view of a magnetic tape head with three modules according to one embodiment, wherein all modules are generally located along parallel planes. Fig. Figure 6 is a side view of a magnetic tape head with three modules that have a touching (angled) configuration. Fig. Figure 7 is a side view of a magnetic tape head with three modules that have a wrap-around configuration. The Fig. Figures 8A to 8F are representative partial views of shingle-shaped overlapping data tracks according to various embodiments. Fig. Figure 9 is a flowchart of a procedure according to one embodiment. The Fig. Figures 10A to 10B are graphical representations of the byte / C2 write-back error rate as a function of the lateral read offset before and after applying a lateral write position offset. Fig. Figure 11 is a flowchart of a procedure according to one embodiment. Fig. Figure 12A is a representation of a band with shingle-shaped overlapping traces, which according to one embodiment are written in a non-snake-like manner. Fig. Figure 12B is a representation of a band with shingle-shaped overlapping traces, which, according to one embodiment, are written in a serpentine manner. Fig. Figure 12C is a representation of a tape with shingle-shaped overlapping traces written in a serpentine pattern and, according to one embodiment, having a directional buffer. Fig. Figure 13 is a flowchart of a procedure according to one embodiment. Fig. Figure 14 is a representative representation of a tape with shingle-shaped overlapping data tracks according to one embodiment. Fig. Figure 15A is a representative representation of a shingle-shaped overlapping data track according to one embodiment. Fig. Figure 15B is a representation illustrating readback errors as a function of the offset of the reading device according to one embodiment.

[0017] It should be noted that the Fig. 1A, Fig. 1B and Fig. 2. Represent the arrangement according to the known state of the art. DETAILED DESCRIPTION

[0018] The following description is provided for the purpose of illustrating the general basic ideas of the present invention and is not intended to limit the concepts claimed herein. Furthermore, certain features described herein can be used in combination with other described features in any of the various possible combinations and permutations.

[0019] Unless otherwise stated herein, all terms shall be given their most comprehensive interpretation and meanings as derived from the specification and understood by experts and / or defined in dictionaries, treatises, etc.

[0020] It should also be noted that the singular forms “ein” and “der / die / das” used in the specification and the attached claims include the plural forms unless otherwise stated.

[0021] The following description discloses several preferred embodiments of magnetic storage systems as well as their operation and / or components.

[0022] In a general embodiment, a method includes acquiring information on how an arrangement of writing devices writes and / or should write when recording with overlapping tracks onto a magnetic medium, and using the acquired information, calculating data describing a lateral writing position for use during writing, such that the overlapping track edges are aligned according to a format.

[0023] In a further general embodiment, a method includes detecting a lateral offset from a nominal writing position and applying the lateral offset to reposition a writing position of an arrangement of writing devices relative to a nominal writing position when writing in a first direction.

[0024] In another general embodiment, a product includes a magnetic recording medium and data indicating whether a lateral offset of the writing position was used during writing.

[0025] In a further general embodiment, a computer program product includes a computer-readable storage medium containing program instructions embodied therein, wherein the program instructions can be executed by a control unit to cause the control unit to execute one or more of the preceding methods.

[0026] Fig. Figure 1A illustrates a simplified tape drive 100 of a tape-based data storage system that can be used in the context of the present invention. Although in Fig. Figure 1A shows a specific implementation of a tape drive; however, it should be noted that the embodiments described here can be implemented in the context of any type of tape drive system.

[0027] As shown, a tape feed cassette 120 and a take-up reel 121 are provided to hold a tape 122. One or more of the reels can be part of an interchangeable cassette and are not necessarily part of the drive 100. The tape drive, such as the one in Fig. The illustrated tape drive 1A can further include drive motor(s) for driving the tape feed cassette 120 and the recording reel 121 in order to move the tape 122 over a tape head 126 of any type. Such a head can include an arrangement of reading devices, writing devices, or both.

[0028] Guides 125 guide the tape 125 over the tape head 126. Such a tape head 126 is connected to a control unit 128 via a cable 130. The control unit 128 can be a processor and / or a logic circuit for controlling all subsystems of the drive 100, or it can contain such components. Typically, the control unit 128 controls head functions such as servo tracking, data writing, data reading, etc. The control unit 128 can contain at least one servo channel and at least one data channel, each of which contains a data flow processing logic circuit configured to process and store information to be written to and / or read from the tape 122.The control unit 128 can be operated according to logic known from the prior art as well as logic disclosed herein and can thus be considered a processor for any of the tape drives described herein in various embodiments. The control unit 128 can be connected to a memory 136 of any type, which can store instructions that can be executed by the control unit 128. Furthermore, the control unit 128 can be configured and / or programmable to execute or control some or all of the procedures described herein. Therefore, the control unit 128 can be considered to be configured to perform various operations by means of logic circuits programmed in one or more chips, modules, and / or blocks; software, firmware, and / or other instructions for one or more processors, etc., and combinations thereof, are available.

[0029] Cable 130 can contain read / write circuits to transmit data to the head 126 for recording on tape 122, and to receive data read from tape 122 by the head 126. An actuator 132 controls the position of the head 126 relative to tape 122.

[0030] Furthermore, an interface 134 can be provided for data exchange between the tape drive 100 and an (internal or external) host, to send and receive data, and to control the operation of the tape drive 100 and transmit the status of the tape drive 100 to the host, as is clear to a specialist.

[0031] Fig. Figure 1B illustrates an exemplary tape cassette 150 according to one embodiment. Such a tape cassette 150 can be used in a system like the one described in Fig. Figure 1A is used. As shown, the tape cassette 150 contains a housing 152, a tape 122 inside the housing 152, and a non-volatile memory 156 connected to the housing 152. In some approaches, the non-volatile memory 156 can be embedded in the housing 152, as shown in Fig. Figure 1B shows that in other embodiments, the non-volatile memory 156 can be attached to the inside or outside of the housing 152 without modifying the housing. The non-volatile memory can, for example, be embedded in a self-adhesive label 154. In a preferred embodiment, the non-volatile memory can be a flash memory unit, a ROM unit, etc., which is embedded on or connected to the inside or outside of the tape cartridge 150. The non-volatile memory can be accessed by the tape drive and the tape operating software (the drive software) and / or other units.

[0032] Fig. Figure 2 illustrates an exemplary side view of a lapped, bidirectional magnetic tape head 200 with two modules, which can be implemented in the context of the present invention. As shown, the head comprises a pair of base bodies 202, each equipped with a module 204 and mounted at a small angle □ to each other. The base bodies can be U-shaped carriers bonded together. Each module 204 comprises a substrate 204A and a cover 204B with a thin-film section, generally referred to as a 'gap', in which the read and / or write devices 206 are formed. In use, the tape 208 is moved over the modules 204 along the media (tape) support surface 209 in the manner shown, in order to read data from and write data to the tape 208 using the read and write devices.The wrap angle □ of the tape at edges extending towards and away from the flat media support surfaces 209 is usually between about 0.1 degrees and about 3 degrees.

[0033] The substrates 204A are typically made of a wear-resistant material such as ceramic. The covers 204B are made of the same or a similar ceramic as the substrates 204A.

[0034] The read and write devices can be arranged in a piggyback or mixed configuration. An illustrative piggyback configuration has a (magnetically conductive) write transducer above (or below) a (magnetically shielded) read transducer (e.g., a magnetoresistive read device, etc.), with the poles of the write device and the shields of the read device generally separated. An illustrative mixed configuration has a shield of the read device in the same physical layer as a pole of the write device (hence "mixed"). The read and write devices can also be arranged in a nested configuration. Alternatively, each arrangement of channels can consist of only read devices or only write devices. Each of these arrangements can include one or more servo track read devices for reading servo data from the medium.

[0035] Fig. Figure 2A illustrates the belt contact area 209 of one of the modules 204, viewed from a line 2A of Fig. 2. A representative band 208 is shown in dashed lines. The module 204 preferably has a sufficient length to be able to support the band as the head moves stepwise between data areas.

[0036] In this example, tape 208 contains 4 to 32 data areas, e.g., with 16 data areas and 17 servo tracks 210 as in Fig. Figure 2A shows a half-inch wide tape 208. The data areas are defined between servo tracks 210. Each data area can contain a number of data tracks, for example, 1024 data tracks (not shown). During read / write operations, the read and / or write devices 206 are positioned on specific track positions within one of the data tapes. External read devices, sometimes referred to as servo read devices, read the servo tracks 210. The servo signals are, in turn, used to keep the read and / or write devices 206 aligned to a specific set of tracks during the read / write operations.

[0037] Fig. 2B shows a plurality of reading and / or writing devices 206, which are located in a column 218 of module 204 in circle 2B of Fig. 2A are formed. As shown, the arrangement of read and write devices 206 includes, for example, 16 write devices 214, 16 read devices 216, and two servo read devices 212, although the number of elements can vary. Illustrative embodiments include 8, 16, 32, 40, and 64 active read and / or write devices 206 per arrangement, and alternatively, nested configurations have odd numbers of read and write devices, such as 17, 25, 33, etc. One illustrative embodiment includes 32 read devices per arrangement and / or 32 write devices per arrangement, with the actual number of converter elements potentially being larger, e.g., 33, 34, etc.Therefore, the magnetic tape can move more slowly, which can reduce speed-induced tracking and mechanical problems and / or require fewer "wraps" to fill or read the tape. While the read and write devices can be arranged in a piggyback configuration as shown in... Fig. As shown in Figure 2B, the read devices 216 and the write devices 214 can also be arranged in a nested configuration. Alternatively, each arrangement of read devices and / or write devices 206 can consist solely of read devices or solely of write devices, and the arrangements can include one or more servo read devices 212. As seen when considering the Fig. 2 and 2A to 2B can be determined, each module 204 can contain a complementary set of reading devices and / or writing devices 206 for such things as bidirectional reading and writing, the ability to read while writing, backward compatibility, etc.

[0038] Fig. Figure 2C shows a partial view of a magnetic tape support area of ​​complementary modules of a magnetic tape head 200 according to one embodiment. In this embodiment, each module has a plurality of read / write (R / W) pairs in a piggyback configuration formed on a common substrate and an optional electrically insulating layer 236. The write devices, illustrated by the write transducer 214, and the read devices, illustrated by the read transducer 216, are aligned parallel to a predetermined direction of travel of a magnetic tape medium across it to form an R / W pair illustrated by the R / W pair 222. It should be noted that the intended direction of tape travel is occasionally referred to here as the tape travel direction, and these terms may be used interchangeably.The direction of tape travel can be deduced from the system's design, for example, by checking the guides; observing the actual tape travel direction relative to the reference point; etc. Furthermore, in a system capable of bidirectional reading and / or writing, the tape travel direction is usually parallel in both directions, and therefore both directions can be considered equivalent.

[0039] There can be multiple R / W pairs 222, for example 8, 16, 32 pairs, etc. The R / W pairs 222 are generally shown linearly aligned in one direction, perpendicular to a belt travel direction. However, the pairs can also be aligned diagonally, etc. Servo reading devices 212, whose function is known, are positioned on the outside of the arrangement of R / W pairs.

[0040] The magnetic tape medium generally moves either in a forward or a reverse direction, as indicated by arrow 220. The magnetic tape medium and the head assembly 200 are operated in a signal-transmitting relationship in a manner known in the art. The piggyback MR head assembly 200 contains two thin-film modules 224 and 226 with generally identical construction.

[0041] Modules 224 and 226 are joined together, with a space between their covers 204B (not shown) to form a single physical unit, so that a read-while-write capability can be provided by activating the write device of the preceding module and the read device of the following module, which is aligned parallel to the write device of the preceding module relative to its tape direction.When a module 224, 226 of a piggyback head 200 is formed, layers are generally formed in the gap 218, which is created over an electrically conductive substrate 204A (partially shown), consisting, for example, of AlTiC, for the R / W pairs 222 in the following order: an insulating layer 236, a first shield 232, which is usually formed of an iron alloy such as NiFe(-), CZT or Al-Fe-Si (Sendust), a sensor 234 for detecting a data track on a magnetic medium, a second shield 238, which is usually formed of a nickel-iron alloy (e.g., -80 / 20 at% NiFe, also known as Permalloy), pole tips 228, 230 of the first and second writing devices, and a coil (not shown). The sensor can be of a known type, including those based on MR, GMR, AMR, tunnel magnetoresistance (TMR), etc.

[0042] The poles 228 and 230 of the first and second writing devices can be made of materials with a strong magnetic moment, such as -45 / 55 NiFe. It should be noted that these materials are merely examples and other materials can be used. Additional layers, such as insulation between the shields and / or pole tips and an insulating layer surrounding the sensor, may be present. Examples of insulating materials include aluminum oxide and other oxides, insulating polymers, etc.

[0043] The configuration of the tape head 126 according to one embodiment comprises several modules, preferably three or more. In a write-read-write (WRW) head, outer modules for writing flank one or more inner modules for reading. Fig. 3, which represents a WRW configuration, the outer modules 252, 256 each contain one or more arrangements of writing devices 260. The inner modules 254 of Fig. 3 contain one or more arrangements of reading devices 268 in a similar configuration. Variations of a multi-module head include an RWR head ( Fig. 4) an RRW head, a WWR head, etc. In further variations, one or more of the modules may have pairs of read / write converters. Furthermore, more than three modules may be present. In other approaches, two outer modules may flank two or more inner modules, e.g., in a WRWR, an RWWR arrangement, etc. For simplicity, a WRW head is mainly used here to illustrate embodiments of the present invention. A person skilled in the art, to whom the teachings presented here are addressed, will recognize how permutations of the present invention can be applied to configurations other than a WRW configuration.

[0044] Fig. Figure 5 illustrates a magnetic head 126 according to an embodiment of the present invention, comprising a first, a second, and a third module 302, 304, 306, each containing a belt support surface 308, 310, and 312, respectively, which may be flat, profiled, etc. It should be noted that the term "belt support surface" may give the impression that the surface facing the belt 315 is in physical contact with the belt support surface, but this is not necessarily the case. Instead, only a portion of the belt may be in constant or intermittent contact with the belt support surface, with other portions of the belt floating (or "flying") above the belt support surface on a layer of air, occasionally referred to as an "air bearing." The first module 302 is referred to as the "preceding" module because, in a three-module design, it is the first module the belt encounters when moving in the specified direction.The third module 306 is referred to as the "subsequent" module. The subsequent module follows the middle module and is the last module to come into contact with the belt in a three-module configuration. The preceding and subsequent modules 302 and 306 are collectively referred to as the outer modules. It should also be noted that the outer modules 302 and 306 alternate as preceding modules depending on the direction of movement of the belt 315.

[0045] In one embodiment, the belt bearing surfaces 308, 310, 312 of the first, second and third modules 302, 304, 306 lie on nearly parallel planes (meaning that they contain parallel and nearly parallel planes, for example as in Fig. 6 between parallel and tangential), wherein the belt support surface 310 of the second module 302 is located above the belt support surfaces 308, 312 of the first and third modules 302, 306. As described below, this has the effect that the desired wrap angle □2 of the belt relative to the belt support surface 310 of the second module 304 is generated.

[0046] If the belt contact surfaces 308, 310, 312 lie along parallel or nearly parallel yet offset planes, the belt should intuitively detach from the belt contact surface 308 of the preceding module 302. However, it has been experimentally determined that the negative pressure generated by the projecting edge 318 of the preceding module 302 is sufficient for the belt to remain adhered to the belt contact surface 308 of the preceding module 302. The subsequent edge 320 of the preceding module 302 (the end at which the belt leaves the preceding module 302) is approximately the reference point that defines the wrap angle □2 over the belt contact surface 310 of the second module 304. The belt remains in close proximity to the belt support surface until near the following edge 320 of the preceding module 302. Consequently, read and / or write elements 322 can be arranged near the following edges of the outer modules 302, 306.These embodiments are particularly suitable for write-read-write applications.

[0047] Since the outer modules 302, 306 are attached with a specific offset relative to the second module 304, an advantage of this and other embodiments described here is that the inner wrap angle □□2 is fixed when the modules 320, 304, 306 are connected to each other or otherwise attached to a head. The inner wrap angle □□2 is approximately tan -1 (δ / W), where δ is the height difference between the planes of the belt bearing surfaces 308, 310 and W is the width between opposite ends of the belt bearing surfaces 308, 310. An illustrative inner wrap angle □□2 is in the range of about 0.3° to about 1.1°, although it can be any angle required by the design.

[0048] It is advantageous if the inner wrap angle □□2 on the side of the module 304 receiving the tape (preceding edge) is larger than the inner wrap angle □□3 on the subsequent edge as the tape 315 moves over the subsequent module 306. This difference is generally favorable, since a smaller angle □□3 tends to counteract a previously steeper effective wrap angle.

[0049] It should be noted that the belt contact surfaces 308, 312 of the outer modules 302, 306 are positioned such that they achieve a negative wrap angle at the following edge 320 of the preceding module 302. This is generally advantageous for reducing friction due to contact with the following edge 320, provided that the location of the crowbar region, which forms in the belt where it detaches from the head, is appropriately taken into account. This negative wrap angle also reduces damage from fluttering and chafing to the elements in the preceding module 302. Furthermore, the belt 315 flies over the belt contact surface 312 of the following module 306, so that virtually no abrasion occurs on the elements when the belt moves in this direction.In particular, the tape 315 carries air with it and therefore does not move significantly on the tape support surface 312 of the third module (a certain degree of contact may occur). This is permissible because the preceding module 302 is writing while the following module 306 is inactive.

[0050] Write and read functions are performed by different modules at any given time. In one embodiment, the second module 304 contains a plurality of data and optional servo-read devices 331, but no write devices. The first and third modules 302, 306 contain a plurality of write devices and no read devices, except that the outer modules 302, 306 may contain optional servo-read devices. The servo-read devices can be used to position the head during read and / or write operations. The servo-read device(s) in each module is (are) typically arranged toward the end of the arrangement of read or write devices.

[0051] Since only reading units or adjacent writing units and servo-reading units are present in the gap between the substrate and the cover, the gap length can be significantly reduced. Typical heads feature piggyback-style reading and writing units, with the writing unit positioned above the reading unit. The width of a typical gap is 20 to 25 micrometers. However, irregularities in the belt can cause it to sag, and erosion can occur at the gap. Therefore, the smaller the gap, the better. The smaller gap achievable here results in fewer abrasion-related problems.

[0052] In some embodiments, the second module 304 has a cover, while the first and third modules 302, 306 do not. If no cover is present, a hard coating is preferably applied to the module. A preferred coating consists of diamond-like carbon (DLC).

[0053] At the in Fig. In the embodiment shown in Figure 5, the first, second, and third modules 302, 304, 306 each have a cover 332, 334, 336, which extends the tape contact area of ​​the associated module, effectively positioning the read / write elements away from the edge of the tape contact area. The cover 332 on the second module 304 can be a ceramic cover of a type commonly found on tape heads. However, the covers 334, 336 of the first and third modules 302, 306 can be shorter than the cover 332 of the second module 304, measured parallel to a tape travel direction over the respective module. This allows the modules to be positioned closer to each other. One way to produce shorter covers 334, 336 is to overlap the nominal ceramic covers of the second module 304 by an additional amount.Another possibility is to clad or deposit thin-film coverings over the elements during thin-film processing. For example, a thin-film covering made of a hard material such as Sendust or a nickel-iron alloy (e.g., 45 / 55) can be formed on the module.

[0054] With reduced-thickness ceramic covers or thin-film covers 344, 336, or when no covers are present on the outer modules 302, 306, the distance between the write and read gaps can be reduced to a value of less than approximately 1 mm, e.g., about 0.75 mm, or 50% less than the distance commonly used on the LTO tape head. The open space between the modules 302, 304, 306 can nevertheless be set to approximately 0.5 to 0.6 mm, which is ideal for stabilizing the tape movement over the second module 304 in some embodiments.

[0055] Depending on the belt tension and stiffness, it may be desirable to angle the belt contact surface of the outer modules relative to the belt contact surfaces of the second module. Fig. Figure 6 illustrates an embodiment in which the modules 302, 304, 306 have a touching or nearly touching (angled) configuration. In particular, the belt bearing surfaces of the outer modules 302, 306 are nearly parallel to the belt at the desired wrap angle □2 of the second module 304. In other words, the planes of the belt bearing surfaces 308, 312 of the outer modules 302, 306 are aligned relative to the second module 304 at the desired wrap angle □2 of the belt 315. Furthermore, in this embodiment, the belt lifts off the subsequent module 306, thereby reducing wear on the elements of the subsequent module 306. These embodiments are particularly useful for write-read-write applications. Additional aspects of these embodiments are similar to those described above.

[0056] The strap wrap angles can usually be set to a value approximately midway between the values ​​specified in the Fig. 5 and Fig. 6 embodiments shown are used.

[0057] Fig. Figure 7 illustrates an embodiment in which the modules 302, 304, 306 are arranged in a wrap-around configuration. The tape contact surfaces 308, 312 of the outer modules 302, 306 are angled slightly more sharply than the tape 315 when it is set to the desired wrap angle □2 relative to the second module 302. In this embodiment, the tape does not lift from the subsequent module, allowing it to be used for both writing and reading. Consequently, the preceding and middle modules can perform both write and write operations, while the subsequent module can read data that has just been written. Thus, these embodiments are preferred for write-read-write, read-write-read, and write-write-read applications. In the latter embodiments, covers should be wider than the tape covers to ensure read capability.Wider covers may require a wider gap-to-gap spacing. Therefore, a preferred embodiment employs a write-read-write configuration with shortened covers, thus allowing for a smaller gap-to-gap spacing.

[0058] Additional aspects of the in the Fig. 6 and Fig. The 7 embodiments shown are similar to the aspects mentioned above.

[0059] A 32-channel version of a Head 126 with multiple modules can use Cable 350, which has traces with the same or a smaller pitch than current 16-channel piggyback LTO modules, or alternatively, the connections on the module can be in the form of an organ keyboard for a 50% reduction in cable span. Above / below pairs of unshielded write cables can be used for the write devices, which may include integrated servo read devices.

[0060] The outer wrap angle □1 can be adjusted in the drive mechanism, for example by guides of any type known in engineering, such as adjustable rollers, sliders, etc., or alternatively by cantilevers that are integral with the head. Rollers, for example, have an offset axis that can be used to adjust the wrap angles. The offset axis creates an orbital arc of rotation that allows for precise alignment of the wrap angle □1.

[0061] To assemble the embodiments described above, a conventional assembly with a U-shaped support can be used. Accordingly, the mass of the resulting head can be maintained or even reduced relative to heads of earlier generations. In other approaches, the modules can be constructed as a single unit. A person skilled in the art familiar with the present teachings will recognize that other known methods for manufacturing such heads can be adapted for use in constructing these heads. Furthermore, unless otherwise stated, processes and materials of types known in the art can be adapted for use in various embodiments that are consistent with the knowledge presented here, as will be clear to a person skilled in the art upon reading the present disclosure.

[0062] As mentioned previously, the amount of data stored on the magnetic tape can be increased by overlapping sections of data tracks (e.g., by shingle-like overlapping data tracks), thereby increasing the number of data tracks across the tape. Shingle-like overlap can be used to adjust the width of written tracks, allowing narrower tracks to be written using write devices with a wider legacy system, thus enabling backward compatibility. Consequently, improvements in data storage capacity are achieved. However, these improvements in data storage capacity may come at the cost of readback performance in conventional products.In particular, conventional products can experience a reduction in readback performance resulting from a degree of uncertainty regarding the characteristics of the write devices and, consequently, the characteristics of the tracks written by these devices. For example, the actual dimensions and / or position of one or more write devices in a head may differ from the nominal dimensions and / or position of one or more write devices. This discrepancy between the actual and nominal characteristics of the write devices can lead to edge shifting of overlapping tracks when writing to data storage media.The drive attempts to read back the shingled overlapping tracks in the nominal target read position, but depending on the extent to which shingled overlapping tracks have been shifted from the nominal target position, the shingled overlapping tracks may cause larger readback errors and / or they may not be readable at all.

[0063] The Fig. Figures 8A to 8C illustrate the difference that can exist between nominal target and actual characteristics (e.g., dimensions, positioning, etc.) of the shingle-shaped overlapping tracks. Fig. Figure 8A shows the nominal target characteristics of shingle-overlapping tracks to be written onto a tape, based on the nominal target characteristics of writing devices used to write the shingle-overlapping tracks. Conceptually, this should occur as expected in use. As shown, the reading device is designed to be set up in a position expected to be aligned with the written track 804 on the tape as the tape moves in the tape-travel direction relative to the reading device 802. The dashed line 803 shows the expected edge of the shingle-overlapping track 804, e.g., according to a format.

[0064] However, due to variations in thin-film wafer processing, the actual dimensions of the wafer can differ from the target specifications, even if the wafer dimensions are within tolerances. This results in the positions of the edges of the shingle-like overlapping tracks deviating from the planned arrangement, potentially leading to misalignment on tracks and even skipping onto adjacent tracks.

[0065] For example, if the actual width of the writing device is smaller than the nominal target width of the writing device, the actual width W A the physical trace as in the Fig. 8A and Fig. 8B shown narrower than the target width W D , which results in the characteristics of the in Fig. 8B, the tracks written on the tape 804 differ from the nominal target characteristics of the tracks, as in Fig. 8A shown. Although the center lines 805 of the written traces (before the shingle-shaped overlap) remain the same, and the width W S the shingle-shaped overlapping track is in the Fig. 8A and Fig. 8B the same, the upper edge of the shingle-shaped overlapping track 804 in Fig. However, 8B is offset from its expected position along line 803, perpendicular to the track direction 806, due to the narrower actual width of the writing device (offset). The drive encodes the positions of the read device 802 in the middle of the nominal position of the shingle-shaped overlapping track, as shown in Fig. Figure 8A shows that a significant portion of the reading device 802 is located outside the shingle-shaped overlapping track 804, although it was installed in a position that would be expected to be aligned with the nominal target characteristics of the written track 804.

[0066] As explained in more detail below, in various embodiments the write position is laterally corrected to minimize misregistration, allowing the readable sections of the overlapping tracks to be written in their nominal target position. When a drive then performs a read-back operation, the read mechanism is correctly positioned over the overlapping tracks. Fig. Figure 8C shows a shingle-shaped overlapping track 804, written at the corrected lateral writing position, which was applied to minimize misregistration by the reading devices.

[0067] It is therefore desirable to mitigate the discrepancies between nominal target characteristics and actual characteristics of shingle-like overlapping traces. It should be noted that the offset in the Fig. While 8A to 8C is measured using an outer edge of the data tracks, an offset can be measured according to other approaches using a midpoint of the data tracks or another desired reference point.

[0068] The Fig. 8D to 8F, which have a common numbering system like the Fig. Items 8A to 8C, which show similar components, similarly illustrate the case where the actual width of the writing device is larger than the target width. Fig. Figure 8D illustrates the target width W D a written trace (before a shingle-shaped overlap). Fig. Figure 8E illustrates the effect that occurs when the actual width of the write device is greater than the nominal width of the write device, resulting in the edge of the shingled overlapping track 804 being displaced from its nominal position along a line 803. In various embodiments, the write position is corrected to minimize the displacement, thus enabling shingled overlapping tracks to be written at the intended position determined by the planned arrangement. When the drive then performs a read-back operation, the read device is correctly positioned over the shingled overlapping tracks. Fig. 8F shows a shingle-shaped overlapping track 804, written at the corrected write position that was applied to keep misregistration as small as possible.

[0069] Repositioning the read mechanism was considered to reduce read-back error rates, but it was deemed impractical for removable media where data may be served to multiple drives, each exhibiting a different placement error of overlapping tracks and thus requiring a different read-head repositioning. Similarly, attempts to anticipate and compensate for undesired overlapping track placement errors resulted in a lower achievable areal density. Finally, reducing the width of the read mechanism was considered undesirable because it would result in a lower signal-to-noise ratio of the broadband read-back amplitude.

[0070] Therefore, the various embodiments described here enable precise and optimal implementations of overlapping shingles on magnetic data carriers. By considering the nominal target and actual characteristics of the writing devices, precise, predictable, and optimal characteristics of the overlapping shingles written to the data carrier can be achieved. Consequently, in some embodiments, a given data carrier can be read accurately by a plurality of drives without requiring significant adjustments to the read head positions, as described in more detail below.

[0071] In Fig. Figure 9 shows a flowchart of a process 900 according to one embodiment. The process 900 can be implemented in various embodiments, including each of those described in the Fig. The environments shown in 1 to 7 can be executed. In procedure 900, of course, a larger or smaller number of operations than those shown can be performed. Fig. The 9 operations described in detail are included, which is clear to a person skilled in the art when reading the present descriptions.

[0072] Each step of Method 900 can be performed by any suitable component of the operating environment. In various embodiments, Method 900 can, for example, be partially or completely performed by a control unit (see, e.g., 128 of Fig. 1A), a processor, etc., or another unit in which one or more processors are present. The processor, e.g., processing circuit(s), chip(s), and / or modules implemented in hardware and / or software and preferably comprising at least one hardware component, can be used in any unit to perform one or more steps of Method 900. Illustrative processors include a central processing unit (CPU), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), etc., combinations thereof, or other suitable data processing units known in the art, but not limited to them.

[0073] As in Fig. As shown in Figure 9, Method 900 includes Operation 902, which captures information about how an arrangement of writing devices actually writes and / or writes as expected to a magnetic medium when recording with shingled overlapping tracks. Differences between how writing devices are supposed to write to a magnetic medium and how writing devices actually write and / or write as expected result in degraded write-back performance. Therefore, by capturing information about how an arrangement of writing devices actually writes and / or writes as expected to a magnetic medium, as shown in Operation 902, such information can be used to improve write-back performance, e.g.by setting up a lateral writing position that is laterally offset from an otherwise nominal actual writing position in order to compensate for any discrepancies between actual and nominal target characteristics of writing devices as soon as these become apparent.

[0074] In some embodiments, the information obtained in Operation 902 may indicate that the nominal target and actual characteristics of the writing devices are consistent, i.e., any difference between the nominal target and actual characteristics of the writing devices is within a tolerance. Thus, in some embodiments, an arrangement of writing devices may write data traces exhibiting characteristics that sufficiently match their nominal target characteristics. By further reference to Method 900, an optional decision 904 includes determining whether a difference between an actual performance of a writing device and a nominal target performance of a writing device is acceptable, for example, whether it is within an acceptable range, is less than a predefined value that distinguishes acceptable performance from unacceptable performance, etc.In response to the finding that the difference is acceptable, procedure 900 can terminate or proceed to operation 902, allowing information to be gathered on how another arrangement of write devices writes, e.g., the write devices of an opposing module. Consequently, data can be written and read effectively without establishing a lateral write position. It follows that in some approaches, the application of an offset lateral write position is suspended by user intervention, ignored upon detection of a predefined condition, and so on.

[0075] However, if it is determined that a difference between the actual performance of a writing device and its nominal target performance is unacceptable, Procedure 900 proceeds to Operation 906, in which the acquired information is used to calculate data describing an offset lateral write position for use during writing, such that shingled overlapping trace edges are aligned according to a format. The data describing the lateral write position may, for example, represent a lateral offset to be applied to a nominal write position during write operations, thus facilitating the transition of write operations from the Fig. This results in 8B becoming 8C and 8E becoming 8F. The lateral write position is based, at least in part, on a lateral offset between the nominal target and actual characteristics of writing devices and / or data tracks written by writing devices. In other words, setting a calculated lateral write position during writing eliminates discrepancies (e.g., lateral misregistrations) between the nominal target and actual characteristics of the writing devices. Consequently, in Operation 908, data can be written to magnetic media (e.g., tape) using the data that describes the lateral write position, for example, by applying an offset to the nominal write position.This solution may make it possible for different drives to read the data accurately without having to attempt to compensate for offsets of overlapping track edges away from the nominal read position by repositioning the read position, since the data is written to the correct position from the outset.

[0076] Furthermore, according to some approaches, the lateral write position can be adjusted to compensate for additional track characteristics, for example, to avoid and / or compensate for curved edges of the magnetic transitions that form along the edges of the data tracks. According to one example, the lateral write position can be repositioned laterally by an additional amount of 2 to 10% of the width of the shingled overlapping track towards the curved edges of the magnetic transitions of the track being read, or vice versa. Therefore, in some embodiments, the readable portion of written tracks can be reduced by the amount of the curved section. In this case, the "edge" of the shingled overlapping track can denote the edge of the properly written section.

[0077] According to some embodiments, the data describing a lateral write position can be calculated once for each drive, e.g., at the manufacturing site. For example, a drive housing (e.g., without a head) can accommodate and connect to a provided head, after which one or more of the processes described here can be performed to determine a lateral write position offset to be implemented in future write operations. In other embodiments, the data describing a lateral write position can be calculated in response to certain criteria, such as a high error rate when receiving a command to perform the calculation (e.g., on demand), during drive repair, after a predetermined period of drive use, etc.

[0078] According to some embodiments, the information acquired during operation 902 can be based on the physical structure of the actual writing devices. In one approach, the information acquired during operation 902 can be acquired by determining the physical characteristics of the magnetic poles of the writing devices in the arrangement. Depending on the desired embodiment, the physical characteristics of the magnetic poles can include stripe height, thickness, width of the track deviation, pitch distance (e.g., center-to-center distance) between writing devices of an arrangement, etc. Furthermore, physical characteristics can be determined using an atomic force microscope (AFM) or another unit for fine analysis, which is obvious to a person skilled in the art, e.g., to identify the position of edges of each pole.

[0079] As mentioned above, characteristics of writing devices can vary as a result of manufacturing inaccuracies, material properties, operator error, etc. For example, an undesired and / or unpredictable positioning of shingled, overlapping tracks can result from a deviation in the width of the write tracks from a nominal target value. This means that two writing devices can have noticeably different physical characteristics, even though their physical characteristics are intended to be essentially the same. Consequently, a data track written by one of the writing devices can differ significantly from a data track written by the second writing device (as shown above in the Fig. 8B and Fig. 8E can be seen). These differences are desirablely taken into account by performing the operations of procedure 900.

[0080] Discrepancies between the nominal target and actual characteristics of the writing devices can result in a lateral shift between the nominal target and actual position of data tracks when writing to data carriers, such as in the case of... Fig. Figures 8A to 8F illustrate this. A data track written to a tape by an array of writing devices may, for example, have a lateral offset between a reference point at a nominal target position of the data track on the tape and a reference point at the actual position of the data track on the tape. By determining the lateral offset corresponding to a predefined array of writing devices, data describing a lateral write position for use during writing can be calculated, ensuring that the edges of shingled, overlapping tracks are aligned according to a format. Therefore, setting the calculated lateral write position when writing data to a magnetic storage medium can result in improved magnetic track placement and reduced read-back error rates.

[0081] Furthermore, as mentioned above, information about how an array of writing devices actually writes and / or should write data to a storage medium can be acquired from various sources and / or using different processes. According to further embodiments, information about how an array of writing devices actually writes and / or should write data to a magnetic storage medium when recording with shingled overlapping tracks can be acquired by evaluating the writing performance of an array of writing devices in each drive. It should be noted that the various embodiments described here can be implemented in embodiments comprising multiple writing devices that may be capable of writing multiple tracks simultaneously.Therefore, there may be a gap between each of the multiple writing devices in a given embodiment, thereby enabling simultaneous writing with shingle-like overlapping tracks on multiple tracks, as is clear to a person skilled in the art upon reading the present description.

[0082] One approach involves capturing information about how an array of writing devices actually writes, and / or should write, to a magnetic storage medium using overlapping, shingled tracks. This information can be obtained by imaging the magnetic domains of the data tracks after they have been written to the magnetic storage medium by the array of writing devices. Thus, the actual data being written by the array of writing devices can be examined to determine how the array writes, and / or should write, to the magnetic storage medium. Depending on the desired approach, imaging the magnetic domains of written data tracks can be performed using a magnetic force microscope (MFM), magnetic flux development, and other techniques.By graphically representing the magnetic domains of written data tracks, characteristics of the corresponding arrangement of writing devices can be derived and, ideally, used to calculate data describing a lateral write position offset to be used during writing (see, for example, Operation 906 above). This offset can be partially derived, for example, by determining the widths of sections of the written tracks that have straight (non-curved) transitions. Furthermore, setting the calculated lateral write position when writing data to a magnetic storage medium results in improved magnetic track placement and reduced readback error rates.

[0083] According to one exemplary embodiment, an arrangement of writing devices can be used to write data to a magnetic tape, wherein the head with the writing devices is positioned in a drive at a nominal write position. The nominal write position can be selected using any conventional approach. Depending on the chosen approach, the nominal write position may be, for example, a predefined write position according to a format, a standard write position of the drive, a calculated position, etc. Accordingly, the nominal write position can correspond to nominal target characteristics of the writing devices (e.g., dimensions, positions, etc.).

[0084] After data has been written to tracks by write devices aligned in the nominal write position, a lateral offset separating the nominal target and actual positions of the data tracks can be determined by pivoting a head perpendicular to the track direction while attempting to read data from the tracks. According to one exemplary approach, read devices can be positioned at an outermost position relative to corresponding data tracks, allowing the read devices to begin or attempt to read data from the data tracks. After an event, such as a certain amount of time elapsed, a tape segment being completed, a certain amount of data being read, etc., the position of the read devices can be repositioned.The position of the read devices relative to the data tracks can be changed gradually or incrementally by moving the read devices stepwise across the track direction by a specific, predefined distance, for example, by about 10 nm to about 100 nm per step for about ten or more data records, away from the outermost position. Thus, by continuously repositioning the read devices, they are incrementally repositioned across the track width of the data tracks in various lateral read positions relative to the tracks containing the written data.

[0085] The data read at various lateral read positions can be analyzed to determine the appropriate write offset for use in subsequent write operations. For example, by evaluating the backread information captured by the reading devices as they are pivoted across the data tracks, a preferred lateral read position for the reading devices can be determined. According to an approach that is in no way intended to limit the invention, one of the lateral read positions can be selected as a preferred lateral read position, at least in part, based on an error rate that occurs during reading. For example, the lateral read position corresponding to the lowest error rate that occurs while reading data tracks can be selected as the preferred lateral read position.The error rate can be a C2 error rate, or, depending on the desired embodiment, it can be any measure of the error rate, such as a C1 error rate, a raw bit error rate, a mean bit error rate, an average bit error rate, a mean squared error, etc., as is clear to a person skilled in the art upon reading this description. Furthermore, the selected lateral read position can be used to compute data describing a lateral read position to be set up during writing, such that the edges of shingled overlapping tracks are aligned according to a format. The offset of the selected lateral read position from a nominal position can specify the offset of the edges of shingled overlapping tracks, as in the following examples. Fig. 8B and Fig. 8E, and can thus be used to determine how to reposition the lateral write position. It follows that information relating to the lateral offset for a given arrangement of write devices can be obtained from data written from a nominal write position onto a magnetic recording medium by reading the data at various laterally spaced read positions relative to tracks bearing the written data.

[0086] According to some approaches, data can be read from the data tracks using the same drive as the drive that has the arrangement of write devices that wrote the data tracks. Thus, the selected lateral read position can correspond to the lateral write position specifically offset for the drive.

[0087] However, other approaches allow data to be read from the data tracks using a different drive than the one containing the write array that wrote the data tracks. Specifically, data tracks corresponding to different implementations can be read using an ordinary drive that is distinct from each of the drives containing the write array that wrote the data tracks. The ordinary drive can include a calibrated read head with specified tolerances for the read array. The data describing a lateral write position can be calculated from readback signals from the ordinary drive.It should be noted that the calculated data describing the lateral write position is applied to the drive that wrote the data tracks to correct for subsequently written, shingled, overlapping tracks. The standard drive may optionally include a head with significantly narrower read mechanisms, which can improve accuracy in determining the optimal offset.

[0088] According to another exemplary embodiment, an arrangement of writing devices can be used to write data onto a magnetic tape, wherein a position of the head containing the writing devices is repositioned in a drive relative to the tape. The arrangement of writing devices can be repositioned between different lateral write positions relative to the magnetic data carrier during the writing process, resulting in the edges of the written tracks being laterally positioned at each step towards a subsequent lateral write position. According to one exemplary approach, writing devices can be positioned at an outermost position relative to corresponding data tracks, allowing the writing devices to begin writing the data tracks. After an event, e.g.,After a certain amount of time has elapsed, a certain section of tape has been traversed, a certain amount of data has been written, etc., the position of the write devices can be repositioned laterally. The position of the write devices relative to the data tracks can be changed gradually or incrementally by moving the write devices incrementally across the track direction by a certain distance, for example, approximately 10 nm to approximately 100 nm for every ten or more data records, from the outermost position. Thus, as the position of the write devices continues to shift laterally, the write devices pivot incrementally across the width of the data tracks in a transverse direction as data is written to them.

[0089] The data written to the tracks is read by read devices aligned at a predefined, e.g., nominal, read position. The nominal read position can be a predefined read position according to a format, a standard read position of the drive, a calculated position, etc. Consequently, the nominal read position can correspond to nominal target characteristics of the write devices (e.g., dimensions, positions, etc.).

[0090] As the reading devices move across the laterally offset, shingle-shaped, overlapping data tracks and data is read from them, readback information can be captured and evaluated. Furthermore, when evaluating the readback information, data can be calculated that describes a lateral write position for use in future write operations based on the readback information obtained during the read operation. For example, a preferred offset lateral write position can be determined. According to one approach, which is not intended to limit the invention in any way, one of the lateral write positions can be selected as a preferred lateral write position, at least in part, based on an error rate that occurs when reading data while the write device is in that particular lateral position.For example, the lateral write position corresponding to the lowest error rate occurring when writing the data tracks can be selected as the preferred offset lateral write position. In another approach, an algorithm can process information read back from the track written at various lateral positions and output data describing the write position to use, possibly based on a mean bit error rate, a C2 error rate, a mean squared error rate, etc.

[0091] Unlike writing at a specific location and pivoting the reading devices across it to determine a preferred lateral reading position, the writing devices can be moved stepwise across the tape perpendicular to the track direction while data is being written to the tape, so that reading devices can read the data at a set of nominal reading positions to determine a preferred lateral writing position.

[0092] As described above, the data can be read by the same drive as the drive containing the array of write devices that wrote the data tracks, thus specifically correlating the offset lateral write position with the given drive. However, in other approaches, data can be read from the data tracks using a different drive than the one containing the array of write devices that wrote the data tracks. The ordinary drive may contain a calibrated read head with small target tolerances for the read device. The calculated data describing a lateral write position can therefore be based on calibration data of both the read and write devices.It should be noted that the calculated data describing the lateral write position is applied to the drive that wrote the data tracks to correct shingled overlapping tracks that will be written in the future.

[0093] Once an offset lateral write position has been determined using one of the processes described and / or proposed herein, the offset lateral write position is preferably applied to future writing operations of shingled overlapping tracks. As described above, the offset lateral write position can be used to reposition a write position of the arrangement of writing devices relative to a nominal write position so that it better reflects the actual characteristics of the writing and / or reading devices of a given drive. Applying the offset lateral write position to future writing of shingled overlapping tracks can result in improved magnetic track placement, reduced read-back error rates, and improved interchangeability of tapes written in this manner.

[0094] In Fig. Figure 10A shows a graph 1000 of the byte / C2 readback error rate as a function of the lateral read offset (lateral read position) that occurs when reading a tape using conventional processes. The results shown in graph 100 are obtained from writing data tracks to and reading data tracks from a tape, relying on nominal target characteristics of the write and read equipment. However, as previously described, there can be differences between the nominal target and actual characteristics of write equipment, resulting in discrepancies between intended and actual data tracks, as shown, for example, in the Fig. As can be seen in sections 8A to 8F. Accordingly, a read device may be aligned at a position where it is expected to be aligned with a data track according to the nominal characteristics of an arrangement of write devices, where the actual characteristics of the written track may differ, resulting in read devices being misaligned with respect to the track and possibly even encompassing adjacent tracks.

[0095] In Fig. 10A represents "0" on the x-axis of graph 1000, the optimal read position when reading tracks from an existing tape according to the planned arrangement. However, the peak values ​​of the curves illustrated in graph 1000 represent the highest achievable byte / C2 error rate, which is achieved by the read devices forcibly encompassing the tracks in lateral steps from one side to the other. Therefore, the peak values ​​of the curves represent the optimal actual read position determined for the read devices when reading from the tape. It follows that the assumption that the nominal target characteristics of shingled overlapping tracks reflect the actual characteristics of shingled overlapping tracks produces inaccurate results for both forward and reverse tape travel directions.

[0096] In sharp contrast, the graphic representation 1050 illustrates Fig. Figure 10B shows the results obtained after setting up an offset lateral writing position, achieved using an approach described herein. Similar results can be expected using any of the approaches mentioned here. As illustrated in Figure 1050, “0” on the x-axis (the optimal read position according to the nominal design) represents a significant alignment with the peak values ​​of the curves (the optimal actual read position) for both the forward and reverse tape directions. Consequently, by setting up an optimal lateral writing position to account for differences between the nominal target and actual characteristics of the writing devices, improved reverse read performance can be desirablely achieved.

[0097] As mentioned above, however, it is not strictly necessary to establish an offset lateral write position when writing to magnetic media. In some embodiments, the nominal target and actual characteristics of the write devices may match, with any difference between the nominal target and actual characteristics of the write devices being within a specified tolerance, etc. Thus, in some embodiments, an arrangement of write devices can write data tracks exhibiting characteristics that match their nominal target characteristics. Consequently, data can be written and effectively read without establishing an offset lateral write position. It follows that in some approaches, the application of an offset lateral write position is suspended by user intervention, ignored upon detection of a predefined condition, etc. (see, e.g.,the above-mentioned decision 904).

[0098] In Fig. Figure 11 shows a flowchart of a process 1100 according to an illustrative embodiment. According to the present invention, the process 1100 can be implemented in any of the embodiments shown in the Fig. The environments shown in Figures 1 to 7, among others, are carried out in various embodiments. As will be clear to a person skilled in the art upon reading the present descriptions, the method may of course contain more or fewer operations than those shown in Figure 1100. Fig. 11 are specifically described.

[0099] Each step of Method 1100 can be performed by any suitable component of the operating environment. In various embodiments, Method 1100 can, for example, be partially or completely performed by a control unit (see, e.g., 128 of Fig. 1A), a processor, etc., or another unit containing one or more processors. The processor, e.g., processing circuit(s), chip(s), and / or module(s), implemented in hardware and / or software and preferably comprising at least one hardware component, can be used in any unit to perform one or more steps of Method 1100. Illustrative processors include a CPU, an ASIC, an FPGA, etc., a combination thereof, or any other suitable data processing unit known in the art, without being limited thereto.

[0100] As in Fig. Figure 11 shows that method 1100 includes an operation 1102 in which a lateral offset from a nominal writing position for a first writing direction is obtained. According to some embodiments, the lateral offset can be obtained by using one or more operations described above with reference to method 900. Fig. 9 were described.

[0101] In procedure 1100, operation 1104 involves applying the lateral offset to reposition a write position of an array of writing devices from nominal write positions when writing in a first direction. As described above, the lateral offset can be used to determine an offset lateral write position that repositions the write position of the array of writing devices away from a nominal write position, so that the actual characteristics of the writing and / or reading devices are better reflected. Applying the offset lateral write position / offset when subsequently writing shingled, overlapping tracks can achieve improved magnetic track placement and reduced readback error rates.

[0102] Embodiments implementing bidirectional writing may include obtaining a second lateral offset, which is applied when writing in a second direction opposite to the first. Accordingly, method 1100 further includes an optional operation 1106 in which a second lateral offset is obtained for writing in a second direction opposite to the first. Furthermore, the optional operation 1108 includes applying the second lateral offset when writing in the second direction, wherein the second lateral offset is different from the lateral offset obtained in operation 1102.

[0103] Bidirectional writing of overlapping tracks can be performed using serpentine or non-serpentine writing. Furthermore, depending on the converter configuration in a given module, more than one method for writing overlapping data tracks may be possible. Modules that, for example, have a read-write-read (RWR) converter configuration in a magnetic head can perform non-serpentine writing. This is primarily because, with an RWR converter configuration, the same arrangement of write devices can write to adjacent data tracks despite a reversal of the tape direction and / or converter orientation during writing, which is generally achieved with serpentine writing. This can lead to write errors, read-back errors, data loss, and other issues.This reduces the number of errors and lowers the requirements regarding the acceptance of misregistrations, as only one set of track tolerances is relevant. Furthermore, using the same arrangement of write devices to write adjacent data tracks ensures consistency in writing by guaranteeing, for example, precise lateral offset values, lateral write positions, the reading of symmetrical servo patterns, and an overall higher areal density.

[0104] Although the same arrangement of write devices can be used to write adjacent data tracks in both the first and second directions, different offset lateral write positions can be applied to the arrangement of write devices for each of the directions.As mentioned above in Method 1100, a first lateral offset can be obtained and / or applied to reposition the writing position of an arrangement of writing devices from a nominal writing position to an offset lateral writing position when writing in a first direction, wherein a second lateral offset can be obtained and / or applied to reposition the writing position of an arrangement of writing devices from a nominal writing position to another offset lateral writing position when writing in a second direction, which is opposite to the first direction, which would be desirable when a single writing head is used in serpentine writing where the opposite writing edges are used for the opposite directions.

[0105] It should also be noted that in some embodiments, a lateral offset can be predetermined (for example, at the time the tape is written by a specific unit) and stored in memory. Thus, according to some approaches, the lateral offset can be obtained from a media element such as a cassette buffer, from data stored on the actual magnetic medium, etc., as will be described in more detail later. In other approaches, however, the lateral offset can also and / or alternatively be obtained from a memory of a device performing the method, e.g., a tape drive buffer. In still other approaches, the offset can be obtained from a database, a host, a library control unit, etc.

[0106] In one embodiment, an indication that the lateral offset was used during writing can be appended to a data record on the data carrier. Equivalently, metadata describing that certain tracks were written using the write offset can be stored in a memory such as the cassette memory.

[0107] In the Fig. Figures 12A to 12C show representative illustrations of writing shingle-like overlapping tracks according to various embodiments. A shingle-like overlapping track 1204 can be formed on a tape 1202 by writing a track 1206 over a section of a previously written track, thereby defining a shingle-like overlapping track 1204 as the remaining section of the previously written track. In various embodiments, shingle-like overlapping tracks 1204 can be formed by using serpentine or non-serpentine writing, as will shortly become clear.

[0108] As in the representative presentation of Fig. Figure 12A, which is not intended to limit the invention in any way, shows that the orientation of the arrows in each of the tracks represents the tape direction when the corresponding track has been written to the tape 1202, preferably using a single arrangement of writing devices for writing in both directions. Thus, a first offset lateral writing position can be used when writing data to tracks in a first direction, and a second offset lateral writing position can be used when writing data to tracks in a second direction opposite to the first direction. This is not necessarily the case when, as shown, writing is performed with a predefined write head on overlapping tracks.

[0109] It should be noted that a less than ideal configuration with a write-read-write (WRW) transducer in a magnetic head can be used for non-snake-like writing in some embodiments. In these embodiments, it is preferred that when writing data to adjacent data tracks, especially when writing shingled, overlapping data tracks, the same write arrangement is used for the adjacent data tracks. Furthermore, similar to the description above, other write arrangements may not be completely identical due to manufacturing variations and therefore exhibit different alignment characteristics, resulting in data being written differently than intended. For example, the write transducers of a write arrangement may not have the same pitch, spacing, etc.such as the write converters of a different write array, even though uniformity was intended. Therefore, using multiple write arrays to write data to adjacent data tracks can result in slight track placement errors, since the data being written to the tracks may be oriented differently on each pass. In another example, using different write arrays can result in overwriting data on an adjacent track, leading to data loss if this tolerance is not accepted.

[0110] According to a further illustrative embodiment, a module can have a configuration with a WRW converter, which is a preferred configuration for performing serpentine writing. When writing data with a WRW configuration, preferably, depending on the intended tape direction, the preceding write device and the preceding read device are active, while the subsequent write device is inactive. Consequently, the preceding write device can be used to write adjacent data tracks for a first tape direction, while the subsequent write device can be used to write adjacent data tracks for a second tape direction opposite to the first.Again, a first lateral offset can be obtained and / or applied to reposition the writing position of an arrangement of writing devices from a nominal writing position to an offset lateral writing position when writing in a first direction, while a second lateral offset can be obtained and / or applied to reposition the writing positions of an arrangement of writing devices from a nominal writing position to an offset lateral writing position when writing in a second direction that is opposite to the first direction.

[0111] In the representative presentation of Fig. 12B, which is in no way intended to limit the invention, states that the orientation of the arrows in each of the tracks is intended to represent the tape direction when the corresponding track is written onto the tape 1202. In contrast to the representation of Fig. In section 12A, data tracks corresponding to a first tape direction are written to the upper section of a data partition, while data tracks corresponding to a second tape direction are written to the lower section of the data partition. This preferably reduces write errors, read-back errors, data loss, etc., and ensures consistency during writing by, for example, enabling the reading of symmetrical servo patterns.

[0112] Furthermore, it shows Fig. 12C presents another pattern for serpentine writing. A buffer 1210, sometimes referred to as a direction buffer, ensures a distance between the nearest tracks written in opposite directions. In one approach, the amount of lateral repositioning can be slightly reduced from the ideal amount to ensure that no writing errors occur later, for example, by maintaining a sufficient direction buffer.

[0113] The first tracks written adjacent to the direction buffer, and tracks overwritten by the last write operation when the tape is completely full, should desirablely have the same tracking tolerance range as all other shingled overlapping tracks.

[0114] In one approach, the algorithms used to select the optimal write positions take into account the direction buffer and ensure that the newly positioned write positions do not adversely affect the direction buffer, for example by overwriting the direction buffer and possibly a data track on the opposite side of the direction buffer.

[0115] In an embodiment where tracks are written in opposite directions in a serpentine pattern from the outside in, the format can specify that the last track written in one data area overlaps the last track written in the opposite direction in a shingled fashion to maximize the usable area. The algorithm used to select the optimal write positions can take this into account and ensure that no error is introduced at any newly positioned write location, such as by overwriting a portion of the last track written in the opposite direction.

[0116] It follows that various embodiments described here can be implemented with a product containing a magnetic recording medium and data describing an offset lateral write position for use during writing, such that the edges of shingle-like overlapping tracks are aligned according to a format. As described above, the data describing the lateral write position can specify a lateral offset from the nominal write position. In other words, the data describing the lateral write position can represent an amount by which an array of writing devices should be offset from a nominal write position when data is written to the tape so that the actual and nominal target positioning of the data tracks coincide.

[0117] According to an illustrative approach, the data describing the lateral write position can contain information from a drive (see e.g. 100 of Fig. 1A) can be used, which includes an algorithm that calculates the lateral writing position(s). The data may contain values ​​that are input into an algorithm to determine where and / or how a head with an arrangement of writing devices should preferably be positioned so that the edges of shingled, overlapping tracks are aligned according to a format.

[0118] Furthermore, according to some approaches, the data can be stored in a memory connected to the magnetic recording medium. However, according to other approaches, the data can be encoded directly onto the magnetic recording medium itself. For example, the data can be written to a predetermined area of ​​the tape.

[0119] Furthermore, some products onto which data has been written can indicate whether a lateral write position offset was used when writing the data. For example, a tape with shingled, overlapping data tracks written by an arrangement of writing devices with a lateral write position offset may contain an indication that the shingled, overlapping tracks written onto it are aligned as a result of reversing the offset lateral write position. This indication can be stored in a cassette memory, written to a designated area of ​​the tape (e.g., a head section), stored in a tracking table (e.g., a reference table) located not on the medium or in the cassette, but, for example, in a library control unit, etc.Furthermore, information can be provided regarding whether specific wraps of a given tape were written using one or more offset lateral write positions. Thus, a specification can contain information that a drive can use, for example, to determine how to read back-track data from the magnetic recording medium and / or how to perform further writing of overlapping tracks. For instance, a drive can implement lateral offset amounts of the read mechanism (e.g., track tracking) when reading data from a tape written without using an offset lateral write position, and yet also reading data from another tape written using an offset lateral write position, with the drive being able to read data from this tape using a nominal read position.Consequently, drives, accessors, control units, etc., can distinguish between tapes stored in a library and / or its buildings that have aligned, shingle-shaped overlapping tracks and those tapes stored in the library and / or its buildings that have misaligned, shingle-shaped overlapping tracks.

[0120] It follows that a tape described using one of the processes described and / or proposed here is highly interchangeable and can be used with any drive with regard to improved track alignment. This is because the track edges corrected according to the approaches given here more closely approximate the nominal target track edge positions expected as standard, i.e., by default, for the various drives.

[0121] Furthermore, embodiments in which an offset lateral write position is established can be distinguished by comparing the characteristics of the actual write devices on the head with the characteristics of the data tracks written using the write devices. If it is found that the characteristics of the actual write devices on the head differ from the characteristics of the data tracks written using the write devices (i.e., that they do not match), it can be determined that a lateral write position was used to write the data to the data tracks. Exemplary embodiment

[0122] Fig. Figure 13 contains a flowchart illustrating a method 1300 according to an embodiment in use. According to the present invention, the method 1300 can be carried out in any of the environments shown and / or described herein. It is clear to a person skilled in the art, upon reading the present descriptions, that the method 1300 may of course include more or fewer operations than those described in Figure 13. Fig. 13 will be described in detail.

[0123] Each step of Method 1300 can be performed by a suitable component of the operating environment. For example, Method 1300 can be partially or completely performed by a control unit in various embodiments (see, e.g., Figure 128 of Fig. 1A), a processor, etc., or another unit containing one or more processors. The processor, e.g., processing circuit(s), chip(s), and / or module(s), implemented in hardware and / or software and preferably comprising at least one hardware component, can be used in any unit to perform one or more steps of Method 1100. Illustrative processors include a CPU, an ASIC, an FPGA, etc., a combination thereof, or any other suitable data processing unit known in the art, without being limited thereto.

[0124] In Fig. Section 13 describes method 1300 for writing a shingle-shaped overlapping track, for example, using a magnetic head that has write transducers connected to it. To write a shingle-shaped overlapping track, all write offset values ​​belonging to the head must preferably be erased. By erasing all write offset values ​​belonging to the head, the shingle-shaped overlapping track can be written, allowing all misalignments of the writing devices to be determined, as will be explained shortly.

[0125] Furthermore, a shingle-shaped overlapping track is preferably formed by writing three overlapping tracks. Fig. Figure 14 shows tape 1440 with a first written track WT1, a second written track WT2, and a third written track WT3. As shown, tracks WT1 and WT2 overlap in a shingled fashion (e.g., partially overwritten), so that WT2 is sandwiched between WT1 and WT3, defining the outer dimensions (track edges) of the overlapping track. It is preferred that the second written track WT2 is written using known data, while the first and third tracks WT1 and WT3 are written differently than WT2. This allows a drive to detect when it is near or at the track edges of WT2 when reading data written to WT2.

[0126] According to a preferred approach, WT2 can contain formatted data from any source, such as user data, which is clear to a person skilled in the art upon reading this description. The formatted data can, for example, include data that has been deserialized to multiple channels, encoded with error-correcting information, interleaved in time, and / or compressed. In contrast, the first and / or third track, WT1 and WT3, can contain erased data, audio data, etc., or any other data pattern of a different type than the data written to WT2. It should be noted, however, that in some approaches, which are by no means intended to limit the invention, WT2 may contain the same and / or similar data written to it as that written to WT1 and / or WT3, but linearly offset to allow differentiation of the track edges of WT2.

[0127] In Fig. Section 13 contains operation 1304, "Measuring the Read Offset," for example, when reading a shingle-overlapping track such as WT2. The read offset can be measured by optionally positioning a reading device over a shingle-overlapping data track and attempting to read data from the track. In particular, a reading device can be positioned at an extreme lateral position relative to a shingle-overlapping track, and reading can be initiated or an attempt made to read data from the shingle-overlapping track. The extreme lateral position is preferably located above or beyond one of the track edges of the shingle-overlapping track to be read. After an event, such as a certain amount of time elapsed, a tape segment being traversed, a quantity of data being read, etc., the reading device can be repositioned.The position of the read device relative to the data tracks can be gradually changed by moving the read device incrementally away from its outermost position by a specific amount, for example, approximately 10 nm to approximately 100 nm for every ten or more data records, perpendicular to the track direction. Because the read device's position is continuously repositioned, it therefore pivots across the width of the data tracks to cover various lateral write positions relative to the shingled, overlapping track that contains the written data.

[0128] In Fig. Figure 15A shows a reading device 1502 at an outermost position relative to the shingle-shaped overlapping track 1504. Over time, the reading device 1502 can pivot continuously or stepwise across the track 1504 transversely to the track direction 1605 until, for example, an opposite outermost position relative to the shingle-shaped overlapping track 1504 is reached (shown shaded). Since the position of the reading device 1502 relative to the track 1504 changes, it follows that the read performance when reading data from the track 1504 also changes as the track 1504 moves in the intended tape travel direction 1508.

[0129] Fig. Figure 15B contains a graphic 1550 illustrating an exemplary readback performance that can be calculated when the read device 1502 is pivoted over the shingled overlapping track 1504. As shown, the readback performance is worst when it exhibits the greatest number of read errors, which occur when the read device 1502 is positioned approximately at an extreme position relative to the shingled overlapping track 1504. However, as the read device 1502 moves toward the center of the shingled overlapping track 1504, the number of read errors occurring at the read device 1502 decreases until a minimum value is reached, before increasing again. The orientation of the read device 1502 relative to the data track 1504 corresponding to the minimum value projected onto the graphic, as indicated, represents an optimal position for the read device.Furthermore, the difference between the optimal position of the reading device and the position corresponding to an offset of zero (i.e., the zero point on the graphical representation 1550) indicates the optimal reading offset.

[0130] After in Fig. Once the read offset has been measured (13), it can be used to determine a write offset that can be applied to a magnetic head that has associated transducers of the writing device. See Operation 1306.

[0131] In one approach, data from a single read device can be used to determine the write position offset. In another approach, data from multiple read devices can be used to determine the write position offset, for example, by using an average, mean, extreme, etc., of the relevant values. Using data from multiple read devices can result in an optimal selection of the compensated write position by averaging the physical variations of the read devices in the array. In one exemplary embodiment, the readback data can be included in the calculation of the compensated write position offset within a predefined median interval.

[0132] Optional operation 1308 involves writing another shingled, overlapping track using the magnetic head, which has the write offset applied to its write position. As described above, a shingled, overlapping track can be formed by writing three overlapping tracks; see, for example, [reference to relevant example]. Fig. 14.

[0133] Furthermore, operation 1310 includes checking whether the read offset is now approximately zero, e.g., in a manner similar to the measurement in operation 1304. Checking the read offset can be performed, for example, by positioning a read device at approximately one of the outermost positions relative to the shingle-overlapping track with the applied write offset and moving it across the shingle-overlapping track perpendicular to the track direction, see e.g., the above. Fig. 15A and Fig.15B. Thus, checking operation 1310 may include determining that the updated optimal read offset is zero or close to zero.

[0134] The present invention may be a system, a method, and / or a computer program product. The computer program product may include a computer-readable storage medium (or media) containing computer-readable program instructions to instruct a processor to execute aspects of the present invention.

[0135] The computer-readable storage medium can be a physical unit capable of holding and storing instructions for use by an instruction execution unit. For example, the computer-readable storage medium can be, but is not limited to, an electronic storage unit, a magnetic storage unit, an optical storage unit, an electromagnetic storage unit, a semiconductor storage unit, or any suitable combination thereof.A non-exhaustive list of more specific examples of computer-readable storage media includes the following: a portable computer floppy disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital versatile disc (DVD), memory stick, floppy disk, a mechanically coded unit such as punched cards or raised structures in a groove in which instructions are recorded, or any suitable combination of the foregoing.A computer-readable storage medium used here should not be designed to contain volatile signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through a waveguide or other transmission media (e.g., light pulses guided through an optical fiber cable), or electrical signals transmitted through a line.

[0136] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to appropriate data processing units (DPUs) or, via a network such as the internet, a local area network (LAN), a wide area network (WAN), and / or a wireless network, to an external computer or storage device. The network may include copper transmission cables, fiber optic cables, wireless transmissions, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each DPU receives computer-readable program instructions from the network and forwards them for storage on a computer-readable storage medium within the DPU.

[0137] The computer-readable program instructions for executing operations of the present invention can be assembly instructions, instructions with instruction set architecture (ISA), machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including an object-oriented programming language such as Smalltalk, C++, or the like, and conventional procedural programming languages ​​such as the programming language "C" or similar programming languages. The computer-readable program instructions can be executed only on a user's computer, partially on a user's computer as a standalone software package, partially on a user's computer and partially on a remote computer, or only on the remote computer or server.In the latter scenario, the remote computer can be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be established to an external computer (e.g., via the internet using an internet service provider). In some embodiments, electronic circuit arrangements, including, for example, a programmable logic circuit arrangement, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), can execute the computer-readable program instructions by using state information from the computer-readable program instructions to personalize the electronic circuit arrangement to perform aspects of the present invention.

[0138] Aspects of the present invention are described here with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the invention. It is clear that each block of the flowcharts and / or block diagrams, and combinations of blocks in the flowcharts and / or block diagrams, can be implemented by computer-readable program commands.

[0139] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or any other programmable data processing device to form a machine such that instructions executed through the processor of the computer or other programmable data processing device generate means for implementing the functions / effects specified in the block or blocks of the flowchart and / or block diagram.These computer-readable program instructions may also be stored in a computer-readable storage medium that can instruct a computer, other programmable data processing device and / or other units to function in a particular manner, such that the computer-readable storage medium with instructions stored therein constitutes a manufacturing item containing instructions that implement aspects of the function / effect specified in the block or blocks of the flowchart and / or block diagram.

[0140] The computer-readable program instructions can also be loaded into a computer, other programmable data processing device, or other unit to effect a series of operational steps to be performed on the computer, other programmable data processing device, or other unit to produce a computer-implemented process, such that the instructions executed on the computer, other programmable device, or other unit implement the functions / effects specified in the block or blocks of the flowchart and / or block diagram.

[0141] The flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this context, each block in the flowchart or block diagrams can represent a module, segment, or section of instructions that includes one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions specified in the block may not occur in the order shown in the figures. For example, two blocks shown sequentially may actually be executed substantially simultaneously, or the blocks may occasionally be executed in reverse order, depending on the functionality involved.It is also noted that each block in the block diagrams and / or flowchart diagrams and combinations of blocks in the block diagrams and / or flowchart diagrams can be implemented by systems based on special hardware that performs the specified functions or effects, or combinations of special hardware and computer instructions.

[0142] Furthermore, according to various embodiments, a system may include a processor and a logic circuit that is integrated into the processor and / or executable by the processor, wherein the logic circuit is configured to perform one or more of the process steps cited herein. "Integrated" means that the processor has an embedded logic circuit as hardware logic, such as an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), etc. "Process-executable" means that the logic circuit is hardware logic; software logic such as firmware, part of an operating system, part of an application program, etc.or a specific combination of hardware and software logic that can be accessed by the processor and is configured to cause the processor to execute a specific functionality when executed by the processor. Software logic can be stored in local and / or remote memory of any memory type known in the art. Any processor known in the prior art can be used, such as a software processor module and / or a hardware processor, such as an ASIC, an FPGA, a central processing unit (CPU), an integrated circuit (IC), etc.

[0143] It is clear that the various features of the preceding systems and / or procedures can be combined in any way, thereby generating a plurality of combinations from the descriptions presented above.

[0144] It is furthermore clear that embodiments of the present invention can be provided in the form of a service that can be used on behalf of a customer.

[0145] The concepts disclosed herein have been presented by way of example to illustrate their numerous features in a plurality of illustrative scenarios, embodiments, and / or implementations. It should be clear that the generally disclosed concepts are to be considered modular and can be implemented in any combination, permutation, or synthesis thereof. Furthermore, any modification, alteration, or correspondence of the features, functions, and concepts disclosed herein that a person skilled in the art would recognize upon reading the present descriptions should also be considered to be within the scope of this disclosure.

[0146] Although various embodiments have been described above, it should be clear that these are merely examples and not limiting. Thus, the breadth and scope of an embodiment of the present invention should not be limited by any of the exemplary embodiments described above, but should only be defined in accordance with the following claims and their substitutions.

[0147] It is also noted that further embodiments of the claimed items may exist:

[0148] In one embodiment of a device, it has a logic circuit configured to apply the lateral writing position to reposition a writing position of the arrangement of writing devices from a nominal writing position.

[0149] In one embodiment of a method, the lateral offset is obtained from a memory of a device that performs the method.

[0150] In one embodiment of a method, the process involves obtaining a second lateral offset for writing in a second direction opposite to the first direction; and applying the second lateral offset when writing in the second direction, wherein the second lateral offset is different from the first lateral offset.

[0151] In one embodiment of a method, an appendage includes a statement indicating that the lateral offset was used during writing.

[0152] In a product, the data is stored in a memory that is connected to the magnetic recording medium.

[0153] In a product, the data is encoded on the magnetic recording medium.

[0154] In a product, the data contains information that can be used by a drive to determine how data is read back from the magnetic recording medium.

[0155] In a product, the data indicating whether a lateral writing position offset was used during writing includes an indication of which tracks were written using the lateral writing position offset.

[0156] Furthermore, a computer program product is presented, wherein the computer program product comprises a computer-readable storage medium containing program instructions, wherein the program instructions are executable by a control unit to cause the control unit to execute a procedure comprising: The control unit acquires information about how, when recording on shingle-like overlapping tracks, an arrangement of writing devices writes and / or is supposed to write onto a magnetic medium; and The control unit calculates data using the acquired information to describe a lateral writing position for use during writing, so that edges of the shingle-shaped overlapping track are aligned according to a format.

Claims

[1] Method which features: Gathering information about how an arrangement of writing devices writes and is intended to write when recording shingled, overlapping tracks onto a magnetic data carrier; and Using the collected information, calculate data that describes a lateral writing position for use when writing, so that edges of shingle-like overlapping tracks are aligned according to a format, wherein the information is captured by writing data onto a magnetic recording medium using writing devices of the arrangement, reading data at different lateral read positions relative to tracks containing the written data, and analyzing the data read at the different lateral read positions, and where the data is read by a different drive than a drive with the arrangement of write devices. [2] Method according to claim 1, wherein the information about how an arrangement of writing devices writes in nominal writing positions is captured, wherein the data includes a lateral offset from the nominal writing position. [3] Method according to claim 1, wherein the data is read by a drive, the drive also containing the arrangement of writing devices. [4] Method according to claim 1, wherein the other drive is a calibrated drive. [5] Method according to claim 1, wherein the information is acquired by writing data to a magnetic recording medium using the writing devices of the arrangement, repositioning the arrangement between different lateral writing positions relative to the magnetic medium during writing, reading data at a predefined position and calculating data describing a lateral writing position to be used in subsequent writing, based on readback information acquired during reading. [6] Method according to claim 5, wherein the data is read by a drive, the drive also containing the arrangement of writing devices. [7] Method according to claim 5, wherein the data is read by a drive other than a drive with an arrangement of writing devices. [8] Method according to claim 1, wherein the information is captured by pictorial representation of magnetic domains of data tracks written by the arrangement of writing devices, and / or the information is acquired by determining the physical characteristics of the magnetic poles of the writing devices in the arrangement. [9] The method of claim 1, comprising the application of data that describe the lateral writing position when subsequently writing shingle-shaped overlapping traces. [10] Device comprising: a drive mechanism for guiding a magnetic medium over the arrangement of writing devices; a control unit that is electrically connected to the arrangement of writing devices; and Logic circuit that is integrated into and / or can be executed by the control unit to perform the method according to claim 1.

Images