JP2001014799A - Method of controlling rotary type storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve reliability of re-write processing by off-track detection in a disk device, and to realize reduction in re-try processing time. SOLUTION: In a disk device of a data surface servo system wherein data sectors 17 and servo sectors 16 are made to exist together for an arrangement in the track of a disk medium 2, on-track is checked by using a servo sector 16 (16-2) after the data sector 17 after having finished writing on the data sector at the time of processing a write command to an arbitrary data sector 17 (17-1). Moreover, after having written in the data sector, the device reports to an higher order device that the write command has been completed, and then, checks the on-track by using a servo sector 16 (16-2) after a data sector 17 (17-1). At this time, if an off-track turns out, the device performs re-write processing independently of the higher order device, and also performs alternation processing as necessary.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for controlling a rotary storage device, and more particularly to a technique effective when applied to a method of processing a data write command in a magnetic disk drive.

[0002]

2. Description of the Related Art A magnetic disk drive, which is a kind of rotary storage device, writes and reads data by positioning a WR / RD head for writing and reading on a recording band called a track.

[0003] In recent years, as the size and capacity of magnetic disk devices have been reduced and track densities have improved, servo information has been recorded on the data recording surface of the disk, and WR / WR has been used for reading and writing data.
A data surface servo system in which servo information is read by an RD head and positioning is performed by obtaining position information of the head itself has become mainstream.

[0004] As an example of this system, Japanese Patent Laid-Open No. 5-174 is disclosed.
The configuration of a disk format will be described with reference to FIGS. 3 and 4 by taking as an example a method of deleting an ID area provided for identifying a sector described in Japanese Patent Publication No. 498. The disk format includes a servo sector (SSCT) 16 provided for controlling the position of a head for performing data recording / reproducing operations on a recording medium, and a data sector (DSCT) 17 provided for storing user data.
They are roughly divided into

As shown in the SSCT example, the servo sector 16 has an automatic gain control gap (AGCG) 19, a servo mark (SVMK) 20, and an index mark (IDX).
MK) 21a / sector mark (SCTMK) 21b, track number area (TRK) 22, positioning information (PO
S) 23 and an inter-sector gap (ISG) 24.

The AGCG 19 is an area provided for adjusting the read gain of servo information, and the SVMK 20 is an area provided for detecting the head position of the servo sector 16. IDXMK21a and SCTMK21b are areas provided for identifying the head of a track or sector, and TRK22 is an area for storing a full track number. The POS 23 stores detailed head positioning information between tracks, and controls each of a detailed positioning operation (settling) and a following operation (following) for always positioning the head on a target track. used. The ISG 24 is an area provided for absorbing fluctuations in the rotation of the disk.

On the other hand, the data sector 17 employs a format in which the recording density is constant over the inner and outer circumferences of the disk, and includes the servo sector in the format (DS).
CTB) and the case where it is not included (DSCTA) have different configurations.

[0008] DSCTA has ISG24, PLO25,
It is composed of BS26, DATA27, ECC28 and PAD29.

The ISG 24 is an area provided for absorbing fluctuations in the rotation of the disk as described above. PLO
An area 25 is provided for synchronizing clocks with the read data, and a BS 26 is an area provided for detecting a timing of converting serial data to parallel data. The DATA 27 is an area for storing user data, and the ECC 28 is an area provided for correcting an error in the read-out DATA 27 when the error is found.

The DSCTB is basically in a format in which the SSCT 16 is inserted in the DSCTA, but the PLO 25 and the BS 26 are arranged again after the SSCT 16. This is because at the time of reading, when passing through the SSCT 16, the read processing is interrupted once, so that it is necessary to perform clock synchronization and byte synchronization again to perform the read processing again.

In this method, since the data sector 17 does not have an ID portion storing the data sector address (DSA), the data sector address (DSA) is set to the servo sector 1.
6 using the servo sector address (SSA).
The SSA can be obtained by setting the address of the servo sector 16 including the above IDXMK 21a to 0 and incrementing the address by one each time the SCTMK 21b of the subsequent servo sector 16 is detected.

When the SSA is obtained, a DSA corresponding to the SSA can be obtained using the address conversion table. This address conversion table can be easily created from the ratio of the number of servo sectors 16 and the number of data sectors 17 arranged in a track in units of a track.

As described above, the data sector address is obtained, and data write / read processing is performed on the data sector set in the area between the servo sectors.

[0014]

The above disk device has the following technical problems.

Since the servo sectors are usually set at a certain interval as shown in FIG. 3, the determination whether the WR / RD head is in the on-track state or the off-track state with respect to the target track is made only at the servo sector interval for each servo sector. I can't. In FIG. 3, for example, when a write command for the data sector 17-1 is executed, it must be in an on-track state at the time of writing the data sector 17-1. Actually, if it is confirmed that the servo sector 16-1 is on-track before the data sector 17-1, the write operation is performed on the assumption that the data sector 17-1 is also on-track. However, if the servo sector 16-1 confirms on-track and then off-tracks due to an external impact or the like, or if the servo sector 16-1 erroneously determines on-track due to an error in reading servo information or a medium defect, the original The write operation is performed in a state where the track is off-track from the position. Since off-track cannot be detected at the end of the writing of the data sector 17-1, the disk device determines that the writing of the data sector 17-1 has been performed normally, and ends the write command normally.
However, since writing is performed in the off-track state, there is a concern that data written in the data sector 17-1 cannot be read normally.

If this abnormal write operation can be detected,
A retry operation of repositioning the WR / RD head at the original position and performing the write operation again becomes possible.

An object of the present invention is to provide a rotary storage device in which data sectors and servo sectors are arranged in a track on a rotary storage medium in a mixed manner, whereby the reliability of data write processing can be improved. The purpose of the present invention is to provide a control technology.

Another object of the present invention is to provide a rotary storage device in which data sectors and servo sectors are mixedly arranged in a track of a rotary storage medium and capable of improving the throughput of data write processing. An object of the present invention is to provide a device control technique.

Another object of the present invention is to improve the throughput of data write processing and improve the reliability of data write processing in a rotary storage device in which data sectors and servo sectors are mixedly arranged in a track of a rotary storage medium. It is an object of the present invention to provide a control technology of a rotary storage device which can achieve both improvement of the storage device.

[0020]

According to the present invention, a data sector in which normal data is recorded and a servo sector in which servo control information is recorded are mixedly arranged in a track set on a rotary storage medium. A first step of executing a data write command for a data sector, and a data write command based on servo control information of a servo sector located behind the data sector on which the data write command was executed. A second step of confirming whether or not the data write command has been executed on-track, and a third step of reporting the completion of the data write command to the host device when it is confirmed that the data write command has been executed in the data sector on track. And to execute.

More specifically, as an example, in the above-described example in FIG. 3, an end report to the host computer performed at the end of the writing of the data sector 17-1 is given by
There is provided means for performing the on-track determination by the means for determining on-track / off-track in the servo sector 16-2 next to the data sector 17-1. If the servo sector 16-2 is determined to be off-track,
The reliability of the writing process is improved by providing a means for performing a necessary retry process such as repositioning the WR / RD head at the original position and performing the writing operation again.

Although this technique can improve the reliability of the write processing, this technique has a technical problem of increasing the redundancy time of the write processing time. As described above, in the description of FIG. 3, after writing to the data sector 17-1, the unit waits until the next servo sector 16-2 and reports the end to the host computer when the on-track is determined in the servo sector 16-2. , Data sector 17-
The time from the end of writing 1 to the on-track determination in the servo sector 16-2 is a redundant time. Off-track rarely occurs, and the writing process is usually terminated without off-track. Therefore, in order to improve the reliability of the writing process, this redundant time always occurs in the writing process and deteriorates the performance.

Therefore, according to the present invention, a rotating sector in which data sectors for recording normal data and servo sectors for recording servo control information are mixedly arranged in a track set on a rotary storage medium. In the method of controlling a storage device, a first step of immediately reporting the completion of a data write command to a host device immediately after the execution of a data write command for a data sector, and a step of reporting a servo sector behind the data sector on which the data write command has been executed. A second step of checking whether the data write command is performed on-track based on the servo control information, and determining that the data write command was not executed on-track in the data sector (it was off-track) The third step is to retry the data write command independently of the host device when Tsu and up, to run.

FIG. 3 will be described in the same manner as described above. When the writing of the data sector 17-1 has been completed normally, at this time, the end of the write command is reported to the host computer. Thereafter, on-track / off-track determination is performed in the servo sector 16-2, and necessary retry processing is performed when off-track is detected. This means reports the end of the write command to the host computer at the end of the writing of the data sector 17-1, and the above-mentioned redundant time does not occur. Further, by performing the retry operation after the command completion report to the host computer, the retry processing time is not included in the redundant time, so that the performance does not deteriorate due to the retry processing.

Further, when the retry processing does not end normally, for example, when an off-track occurs even in the retry processing and the retry processing does not end normally even after performing the retry processing a certain number of times or more, the write sector is changed independently of the host computer. Automatic replacement processing means for performing replacement writing assigned to the sector may be provided.

[0026]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIGS. 1 and 2 are flowcharts showing an example of the operation of an embodiment of the method for controlling a rotary storage device according to the present invention. FIG. 3 is a flowchart showing the control of the rotary storage device according to this embodiment. FIG. 4 is a conceptual diagram illustrating an example of a sector arrangement in a disk medium of a disk device in which the method is implemented. FIG. 4 is an example of a track format in the disk medium of the disk device in which the method of controlling a rotary storage device according to the present embodiment is implemented. FIG. 5 is a conceptual diagram showing an example of the configuration of a disk device in which the method of controlling a rotary storage device according to the present embodiment is implemented.

First, an outline of the configuration of the disk device of the present embodiment will be described with reference to FIG. 5, 2 is a disk medium, 3 is an R / W head, 4 is a data processing device, 5 is a host I / F control unit, 6 is a CPU,
7 is a buffer controller, 8 is a data buffer, 9 is a servo controller, 10 is a drive I / F controller, 11 is an ECC controller, 12 is a motor driver such as a voice coil motor for driving the R / W head 3, Reference numeral 13 denotes a signal processing device, 14 denotes an R / W amplifier, and 15 denotes a host computer.

As illustrated in FIG. 3, in the disk medium 2 of the present embodiment, a plurality of tracks are arranged concentrically, and each of the tracks has a plurality of data sectors 17 and servo sectors 16 in the circumferential direction. It is arranged.

FIG. 4 illustrates an example of the format of individual data sectors and servo sectors in more detail. Hereinafter, the configuration of the format according to the present embodiment will be described. The disk format is a servo sector (SSC) provided to control the position on the disk medium 2 of the R / W head 3 for performing data recording / reproducing operations.
T) 16 and a data sector (DSCT) 17 provided for storing user data.

In the present embodiment, when adopting a format in which the recording density is constant over the inner and outer circumferences of the disk medium 2, the number of data sectors 17 in each track differs. On the other hand, the same number of servo sectors 16 are arranged for each track at positions equally dividing the circumferential direction of the track. Therefore, as described later, in the data sector 17, the data sector (D) including the servo sector therein is included.
SCTB) 17b and a data sector not included (DSCT)
A) There is 17a.

Each servo sector 16 has an automatic gain control gap (AGCG) 19 and a servo mark (SVMK).
20, index mark (IDXMK) 21a / sector mark (SCTMK) 21b, track number area (T
RK) 22, positioning information (POS) 23, and inter-sector gap (ISG) 24.

The AGCG 19 is an area provided for adjusting the read gain of the servo information, and the SVMK 20 is an area provided for detecting the head position of the servo sector 16. IDXMK21a and SCTMK21b are areas provided for identifying the head of a track or sector, and TRK22 is an area for storing a full track number. The POS 23 stores detailed head positioning information between tracks, and controls each of a detailed positioning operation (settling) and a following operation (following) for always positioning the head on a target track. used. The ISG 24 is an area provided for absorbing fluctuations in the rotation of the disk.

The servo sector 16 is generally recorded using a dedicated servo write device. This is because, in order to position the head on the track, it is necessary to perform head position control using, for example, a dedicated positioning device using a laser. In the present invention, the servo write method is not a problem but a generally used method.
Servo writing may be performed.

On the other hand, the data sector 17 employs a format in which the recording density is constant over the inner and outer circumferences of the disk. As described above, the data sector 17b includes the servo sector therein (DSCTB). In the case of the data sector 17a that does not include (DSCTA), the configuration is different.

The DSCTA has an inter-sector gap (IS
G) 24, clock synchronization section (PLO) 25, byte sync section (BS) 26, data section (DATA) 27, error correction code section (ECC) 28, pad data (PAD)
29.

The ISG 24 is an area provided for absorbing fluctuations in the rotation of the disk as described above. PL
O25 is an area provided for synchronizing clocks with read data, and BS26 is an area provided for detecting a timing of converting serial data to parallel data. The DATA 27 is an area for storing user data, and the ECC 28 is an area provided for correcting an error in the read-out DATA 27 when the error is present. The PAD 29 is specific data for filling an empty area up to the next sector boundary.

The DSCTB basically has a format in which the SSCT 16 is inserted into the DSCTA, but the PLO 25 and the BS 26 are arranged again after the SSCT 16. This is because at the time of reading, when passing through the SSCT 16, the read processing is interrupted once, so that it is necessary to perform clock synchronization and byte synchronization again to perform the read processing again.

In this system, since the data sector 17 does not have an ID portion storing the data sector address (DSA), the data sector address (DSA) is set to the servo sector 1
6 using the servo sector address (SSA).
The SSA can be obtained by setting the address of the servo sector 16 including the above-described index mark 21a to 0 and incrementing the address by one each time the sector mark 21b of the subsequent servo sector 16 is detected.

When the SSA is obtained, the DSA corresponding to the SSA can be obtained using the address conversion table. This address conversion table can be easily created from the ratio of the number of servo sectors 16 and the number of data sectors 17 arranged in a track in units of a track.

The operation of each block will be described with reference to FIG. 5, taking a data write operation as an example.

The CPU 6 controls the entire disk device 1. The host I / F control unit 5 includes a host computer 15
To the buffer control unit 7. Also, it receives a command from the host computer 15 and sends it to the CPU 6. The CPU 6 analyzes the command, calculates an address of the data sector 17 for storing data on the disk medium 2, and sets a track address and a head number to the servo control unit 9.

The servo control unit 9 instructs the signal processing device to select a head specified by the head number, and
The servo information is read every 6 and the motor driver 12 is controlled to read / write R / W data on the track specified by the track address.
The head 3 is moved and positioned. IDXPLS indicating the starting point of the track, SCTPLS indicating the boundary of the sector,
It outputs SRVPLS indicating the servo area.

The signal processing device 13 switches to a head corresponding to the head number, and transfers data from the drive I / F control unit 10 to the R / W amplifier 14. The transferred data is recorded on the disk medium 2 via the R / W head 3.

The buffer controller 7 temporarily stores the data from the host I / F controller 5 in the data buffer 8,
The transfer to the drive I / F control unit 10 is controlled. EC
The C control unit 11 generates an ECC for detecting / correcting a reading error in the reading process. The drive I / F control unit 10 is activated by the CPU 6 and manages data transfer and performs sector processing after on-tracking.
Performs a data write (WR) process on the data. After the processing is completed, the CPU 6 is notified of the completion. Furthermore, CPU6
Indicates to the host I / F control unit 5 that the host computer 1
5 is instructed to report a write (WR) command completion.

Next, an example of the operation of the embodiment of the present invention will be described with reference to the flowcharts of FIGS. 1 and 2 and FIGS.
This will be described with reference to FIG.

The feature of this embodiment resides in a method of executing a write command for storing data in the disk device 1 by the host computer 15.

The host computer 15 has the disk device 1
To send a write command and write data.
The host I / F control unit 5 receives these write commands and write data, and sends the commands to the CPU 6 and the write data to the buffer control unit 7. The CPU 6 analyzes the command, calculates the address on the disk medium 2 of the data sector 17 for storing data, and issues a seek command to the servo control unit 9 by specifying a track address and a head number. The servo control unit 9 instructs the signal processing device 13 to select a head specified by the head number, reads out servo information for each servo sector 16, and
2 to move and position the R / W head 3 on the track specified by the track address (step 10).
1).

When the state changes to the on-track state, ONTRACK indicating the on-track state is output (step 102). In addition, after the on-track, if the off-track state due to external impact etc., the ONTRACK is turned off,
ATTENTION indicating an error state is output as needed.
It also outputs IDXPLS indicating the starting point of the track, SCTPLS indicating the boundary of the sector, and SRVPLS indicating the servo area.

The buffer controller 7 temporarily stores the data from the host I / F controller 5 in the data buffer 8,
The transfer to the drive I / F control unit 10 is controlled. The drive I / F control unit 10 is activated by the CPU 6 to identify a data sector on a track, manage data transfer,
A sector process is performed, and a data write process is performed on the data sector 17 (step 103, step 10).
4).

Further, the processing result of the write processing itself executed in steps 103 and 104 is verified (step 105). The verification of the write process itself is as follows.
It is to verify whether or not the write processing itself has been normally executed irrespective of on-track / off-track. Then, the verification result is determined to be normal (OK) and retried (RETR).
Y) It is divided into three cases, a possible error and a non-retryable (FATAL) error. If the error is normal, the following processing is executed. In the case of an error that can be retried (RETRY), the process returns to step 101 to retry. A process error report is made (step 106).

The operation after the write processing for the data sector 17 has a feature of the present embodiment. Hereinafter, the operation of the present embodiment will be described by dividing it into first and second operation examples.

[First Operation Example] As illustrated in the flowchart of FIG. 1, after the write processing for the data sector 17 is completed normally (steps 104 and 105), the servo sector 1 after the data sector 17 on which the write processing has been performed.
6 to determine whether the track is on-track or off-track
A determination is made by TRACK or ATTENTION (step 107).

When it is determined that the track is on-track, it is determined that the write processing has been normally performed, and a normal end is reported to the CPU 6. The CPU 6 instructs the host I / F control unit 5 to report the end of the write command to the host computer 15, and the host I / F control unit 5
5 is notified of the end of the write command (step 10).
8), a series of write command processing ends.

If it is determined in step 107 that the track is off-track, the abnormal end of the off-track error is reported to the CPU 6. The CPU 6 sends a seek command to the servo control unit 9 again, and returns to step 101 to perform a retry operation of performing the write process again as described above.

That is, in the case of the present embodiment, for example, in FIG. 3, when the data sector 17-1 is to be written, in both the servo sector 16-1 on the near side and the servo sector 16-2 on the rear side. , On-track confirmation is performed.

According to the first operation example described above, in this embodiment, the retry processing can be performed by detecting whether or not the write processing of the data sector 17 has been performed in the off-track state. It is possible to improve the reliability of the write command in the ID-less data surface servo method.

[Second Operation Example] In the first operation example described above, the reliability can be improved.
Receives the write command and then returns to the host computer 15
The time required to report the end of the write command is sacrificed. That is, after executing a write command to the target data sector 17, the next servo sector 16
In this case, the rotation waiting time until the on-track determination is performed becomes an overhead. In order to improve this point, the following processing of the second operation example is executed.

Write processing is performed on the data sector 17 in the same manner as described above, and after the write processing ends normally (step 10).
4, step 105), immediately report the normality to the CPU 6, and report the end of the write command to the host computer 15 (step 201). At this time, it is determined whether the servo sector 16 after the data sector 17 on which the write processing has been performed is on-track or off-track by ONTRACK or ATTENTION (step 20).
2). If it is determined to be on-track, no special processing is required. Since the end of the write command is reported to the host computer 15 before the on-track determination,
After the data sector 17 is written, the servo sector 16
However, since a redundant time until the on-track determination is not included in the write command processing time, overhead as in the above-described first operation example does not occur.

If it is determined in step 202 that the track is off-track, an abnormal end of the off-track error is reported to the CPU 6. The CPU 6 sends a seek command to the servo control unit 9 again, and performs a retry operation for performing the write process again as described above (steps 204 to 207). If the retry for the original target data sector 17 has failed, a replacement process for executing a write command for a data sector in another replacement area is performed (step 209).

In the second operation example, the end of the write command is reported to the host computer 15 before the retry operation. Therefore, after the data sector 17 is written, the rotation is performed until the next servo sector 16 determines on-track. Since the waiting time and the retry processing time at the time of retry execution are not included in the write command processing time,
It is possible to improve the reliability of the write command processing by the ID-less data surface servo method without lowering the performance such as the throughput of the write command.

For example, the disk device 1 of the present embodiment
In the case of configuring a disk array in a RAID system, an improvement in write processing throughput
It is possible to reduce the so-called write penalty in the ID, and it can be expected to improve the reliability and throughput of the RAID system.

Among the inventions of the present application, the inventions other than those described in the claims are listed as follows.

<1> A disk device in which, when a write command is executed, a completion command of the write command after the on-track confirmation is performed by means for confirming the on-track after the completion of writing the data to the medium.

<2> When executing a write command in the disk device, if the means for confirming on-track is determined to be off-track after completion of writing data to the medium, retry processing for re-executing the data write operation to the medium is performed. A disk device characterized by performing.

<3> When a write command is executed in the disk device, the end of the write command is reported immediately after the end of writing the data to the medium, and if the on-track confirmation means determines that the track is off-track, the write command ends. A disk device characterized in that, even after the report, the data write operation to the medium is performed again so that the off-track retry process is not included in the execution time of the write command.

<4> When performing a write command in a disk device and performing a retry operation due to an error, by performing a retry operation after reporting the end of the write command, the retry processing is not included in the execution time of the write command. Characteristic disk device.

<5> In the disk device described in <3> and <4>, when the error at the time of the write operation is not recovered, the write area is automatically changed to a different area to write data to the medium. A disk device characterized by improving reliability.

<6><1> or <2> or <3>
Or, a disk such as a disk array, having a plurality of disk devices according to <4> or <5> mounted thereon, and having a housing for fixing them, and a control unit for electrically connecting and controlling the disk devices. Equipment system.

Although the invention made by the inventor has been specifically described based on the embodiments, the present invention is not limited to the above-described embodiments, and can be variously modified without departing from the gist thereof. Needless to say, there is.

For example, the rotary storage device is not limited to a magnetic disk device and the like, and can be widely applied to a general rotary storage device of a data surface servo system.

[0072]

According to the method of controlling a rotary storage device of the present invention, in a rotary storage device in which data sectors and servo sectors are mixedly arranged in a track of a rotary storage medium, the reliability of data write processing can be improved. The effect of being able to improve is obtained.

According to the method for controlling a rotary storage device of the present invention, the throughput of data write processing is improved in a rotary storage device in which data sectors and servo sectors are mixedly arranged in a track of a rotary storage medium. Can be obtained.

According to the method of controlling a rotary storage device of the present invention, in a rotary storage device in which a data sector and a servo sector are arranged in a track on a rotary storage medium, the throughput of data write processing is improved. And an improvement in the reliability of the data write process can be achieved.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating an example of an operation of a control method of a rotary storage device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing an example of the operation of the embodiment of the control method of the rotary storage device of the present invention.

FIG. 3 is a conceptual diagram showing an example of a sector arrangement on a disk medium of a disk device in which a method for controlling a rotary storage device according to an embodiment of the present invention is implemented.

FIG. 4 is a conceptual diagram showing an example of a track format in a disk medium of a disk device in which a method for controlling a rotary storage device according to an embodiment of the present invention is implemented.

FIG. 5 is a conceptual diagram showing an example of a configuration of a disk device in which a method for controlling a rotary storage device according to an embodiment of the present invention is implemented.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Disk device (rotary storage device), 2 ... Disk medium (rotary storage medium), 3 ... R / W head, 4 ... Data processing device, 5 ... Host I / F control part, 6 ... CPU, 7 ...
Buffer controller, 8 data buffer, 9 servo controller, 10 drive I / F controller, 11 ECC controller, 12 motor driver, 13 signal processor, 14
.. R / W amplifier, 15 host computer, 16 servo sector (SSCT), 16-1, 16-2 servo sector, 17 data sector (DSCT), 17a data sector (DSCTA), 17b data sector (D
SCTB), 17-1: data sector, 19: automatic gain control gap (AGCG), 20: servo mark (SV)
MK), 21a ... index mark (IDXMK),
21b: Sector mark (SCTMK), 22: Track number area (TRK), 23: Positioning information (POS),
24: Inter-sector gap (ISG), 25: Clock synchronization unit (PLO), 26: Byte sync unit (BS), 27
... data part (DATA), 28 ... error correction code part (ECC), 29 ... pad data (PAD).

Claims (3)

[Claims] 1. A control method for a rotary storage device in which data sectors in which normal data is recorded and servo sectors in which servo control information is recorded are mixed and arranged in a track set in the rotary storage medium. A first step of executing a data write command for the data sector; and the data write command based on the servo control information of the servo sector located behind the data sector where the data write command was executed. A second step of confirming whether or not the data write command has been executed on-track; and a step of reporting completion of the data write command to a host device when it is confirmed that the data write command has been executed on track in the data sector. 3. A method for controlling a rotary storage device, comprising the steps of: 2. A method of controlling a rotary storage device in which a data sector on which normal data is recorded and a servo sector on which servo control information is recorded are mixed in a track set on the rotary storage medium. A first step of immediately reporting the completion of the data write command to a host device immediately after the execution of the data write command for the data sector; and the servo sector behind the data sector in which the data write command has been executed. A second step of checking whether or not the data write command has been performed on-track based on the servo control information of the above, and when it is determined that the data write command has not been performed on-track in the data sector, Third step of retrying the data write command independently of the host device A method for controlling a rotary storage device, comprising: 3. The method of controlling a rotary storage device according to claim 2, wherein, when said retry fails, a replacement sector different from said data sector in said first step independently of said host device. And performing a replacement process for executing the data write command.