JPH0244582A - Disk data control method - Google Patents

Abstract

PURPOSE:To attain the correction of an error while the data of many errors can be corrected by re-recording the data to another sector when the number of errors is a correctable number and goes to be >=a prescribed number. CONSTITUTION:A central processing unit 12 reads the data of the designated sector from a disk drive device 7 by instruction from a high order device 18 and the error correction of the data is executed by an error correcting circuit 15. When the error is <=6 bytes, the unit 12 transfers the data, for which the error-correction is executed in the circuit 15, to the device 18. Out of the read data of one sector, when the error is >=7-8 bytes, the correcting data are reloaded to the other sector on a disk so that the data reading of the sector can not be impossible. Then, the data of the sector, which is first read, are made invalid. After that, the correcting data are transferred to the device 18.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a disk data control method, and more particularly to a disk data control method for a magneto-optical disk or the like.

Conventional disk devices such as magneto-optical disks read data from the middle of the sector 'C'. In a control device that controls reading and writing of data in such a disk device, an error correction code is added to the data when data is written, and when data is read, errors in the data are detected and corrected using this error correction code. .

This error correction code was one in which, for example, 16 bytes of lead code were added to 100 bytes of data. In this case, 100←16=11
Any 8-byte error within 6 bytes can be corrected.

Therefore, if an error of 9 bytes or more occurs, correction is normally impossible. In other words, it becomes impossible to read f-even.

For this reason, such m-control devices store data, ! : When writing data, the data written immediately after that was read out, the error in that data was counted as Si, and if the error was, for example, 7 bytes or more, control was performed to redirect to another alternative sector (for example, if the error was 7 bytes or more) Gansho 62-200576).

FIG. 3 shows a flowchart when reading data in a conventional control device. When reading data, first one sector of data is read from the disk and error correction is performed (Subject 119.20). Next, since the error g7 is positive up to 8 bytes and seven bytes after 9 bytes cannot be corrected, it is determined whether there are errors of 9 or more bytes (step 21).

If the error is 9 bytes or more, notify the host device to which the disk device is connected that the data cannot be read (Step 22); if the error is 8 bytes or more; Transfer the data to the host device (
Slap 23) was controlled by a control device.

Problems to be Solved by the Invention However, in the conventional control method, when data is written to a disk, the written data is read out immediately after the data is written, and if the condition of the disk medium is bad or something happens to the data, the control method reads out the written data at this time. If the error is, for example, 7 bytes or more, it is simply rewritten to another alternative sector, and only the error is corrected when reading, so after writing, the data can be read without errors, but if the data is read for a long time, the disk Errors occur due to changes over time, and errors tend to increase with the passage of time.
When the number of bytes or more is exceeded, there is a problem that correction using the error correction mark S becomes impossible and it becomes impossible to read the data again.

The present invention has been made in view of the above points, and an object of the present invention is to provide a disk data control method that improves data reliability by rewriting data when reading data.

Means for Solving the Problems The present invention provides a disk data control method for a disk device that records and reproduces digital data to which an error=J positive sign is added sector by sector. a detection means for detecting, and a digital signal corresponding to one digit corrected based on the error correction code when the number of errors detected by the detection means is a correctable number or more based on the error correction code; data +'+f
Control to control the disk device to rewrite data to the sector on the disk f and to make the sector from which the gage digital data has been read unreadable! l'f-stage.

Operation In the present invention, digital data is processed in the procedure shown in FIG. 1, for example. First, when reading digital data from the disk device α, the digital data is read sector by sector (Sub 1).

After one sector's worth of digital data is error corrected (step 2), it is supplied to other equipment (step 5). At this time, the number of errors in one sector is detected by the detection means,
It is determined whether the number of errors is correctable based on the error correction code and is greater than or equal to a certain number (step 3). If the number of errors is correctable or exceeds a certain number, the control means re-records the corrected digital data in another sector on the disk, and the sector from which the digital data was read is made unreadable. Control the device (Step 6) and transfer data to the host device (Step 5)
).

Therefore, when the number of errors exceeds a certain number that can be corrected, data with many errors should be corrected and re-recorded while it is still possible to correct them using an error correction code, in order to re-record in another sector. becomes l'1 chono.

Example FIG. 2 shows a block diagram of one embodiment of the invention.

In the figure, 7 is a disk drive device that drives an optical disk and reads and writes data, 8 is a disk drive device ¥ 7
18 is the disk drive device 7.
Indicates a higher-level device that supplies data to or receives necessary data.

The control muV device 8 has an external communication interface 17 for communicating with the -F device 18, a bag 716 for temporarily storing data, an error correction circuit 15 for correcting errors, and a data exchanger with the disk drive device 8. It consists of an interface 19 for transmitting and receiving data 3, a central processing unit 12 for controlling the above-mentioned circuits, a read/write C randomly accessible memory (RAM) 13, and a read only memory (ROM) 14.

An external communication interface 17, a buffer 16, an error correction circuit 15, and a disk drive interface 9 are connected to a bus 10 for data exchange.

It is also connected to an external communication interface 17, an error correction circuit 15, and a disk drive interface 9 [Yo bus 2], and data transmission is performed by the central processing unit 12, RAM 13, and ROM 14, which are also connected to the bus 2. controlled.

Errors occurring in the f-tater are corrected by an error correction circuit 15 driven by a command from the central processing unit 12, which reads data from the buffer i16 and performs a correction operation. The data corrected by the error correction circuit 15 is returned to the buffer 16 again.

Further, when transferring data to an external host device e118, the external communication interface 17 is driven by a command from the central processing unit 12, data is taken in from the buffer 16, and the data is transferred to the host device 18.

On the other hand, when writing data to a disk, the disk drive device interface 9 takes in data from the back 116 in response to a command from the central processing unit 12 and transfers it to the disk drive device 7. At this time, it is configured to notify the disk drive device 7 in which sector on the disk the data is to be recorded.

Next, the main operations of the apparatus of this embodiment will be explained with reference to FIG. FIG. 1 shows a flowchart for reading data from a disk.

First, upon receiving a data read command from the host device 1B, the central processing unit 12 sends the data to the disk drive device 7 via the disk drive interface 9 based on this command.
Higher ¥'! ; The data in the sector designated by 118 is read out (step 1). Next, error correction circuit 1
5. Errors in the data read from the disk in step 5.
Correct (Step 2). At this time, you can see how many bytes there are errors.

In the central processing unit 12, if there is an error of 9 bytes or more, the error correction circuit 15 cannot correct all the errors, and therefore cannot be read. Unreadable +Q
(Step 4).

In addition, when the error is 6 bytes or more, since the error correction is sufficiently i+J, after 1 error is corrected by the error correction circuit 15, the bus 10 is connected to the external communication interface 1.
7, the data is transferred to the host device 18 (step 5).

If the error on the back of one sector of data read from the disk is 7 or 8 bytes, the next time the same sector is read from the disk, the error will increase due to disk deterioration and become 9 bytes or more, and the same error will occur. To prevent the data in the sector from becoming unreadable,
The corrected data is rewritten to another alternative sector on the disk that is different from the sector that was read out, thereby invalidating the data in the sector that was read out first (step 6).

Thereafter, the corrected data is transferred to the host device 8 (step 5).

Effects of the Invention As described above, according to the present invention, when the number of errors that can be corrected based on the error correction code is greater than a certain number, the error-corrected digital data is re-recorded in another sector. Errors in the digital data are corrected and re-recorded on the disc, increasing the reliability of the data on the disc.Furthermore, since the data is re-recorded after correction, the number of errors is reduced and data can be read out again. It has the advantage of reducing the time required for error correction.

[Brief explanation of the drawing]

Fig. 1 is a flowchart for explaining the operation of an embodiment of the present invention, Fig. 2 is a block diagram of an embodiment of the invention, and Fig. 3 is a flowchart for explaining the operation of a conventional example. . 7... Disk drive device, 8... 1blI control device, 12... Central processing unit, 15... Error correction circuit, 18... Host device. Patent applicant: Victor Japan Co., Ltd. 1 “11”

Claims (1)

[Scope of Claims] A disk data control method for a disk device that records and reproduces digital data added with an error correction code sector by sector, comprising: error detection when reading the digital data from the disk and correcting the digital data; means detects the number of errors in the digital data in the predetermined sector, and when the number of errors in the digital data in the predetermined sector is correctable based on the error correction code and is equal to or greater than the predetermined number, the control means detects the number of errors in the digital data in the predetermined sector; The disk device is configured to re-record the digital data of the predetermined sector corrected based on the error correction code in other sectors on the disk, and to make the sector from which the digital data on the disk was read unusable. A disk data control method characterized by controlling.