JPH03165374A - Optical disk device - Google Patents

Abstract

PURPOSE:To recover the data of an optical disk, to which recording is made defective, by providing a means to generate an error detecting and correcting code to a whole sector belonging to a sector group and to execute error detection and correction by this code. CONSTITUTION:A track error detection and correction part 5 generates the error detecting and correcting code for each sector group, which is composed of the prescribed number of sectors, and executes recording. Thus, even when the sector is damaged over the correcting ability of a sector error detection and correction part 3 by an erroneous operation, etc., after recording the data to the optical disk, the error can be corrected by the error detecting and correcting code in the other sector of the sector group and in the sector group. Further, when a recording area for correction is provided for each sector group and the error detecting and correcting code of the sector group is recorded to the recording area for correction, the correction can be speedily executed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an optical disk device, and more particularly to a device for detecting and correcting errors in data to be recorded and reproduced.

Conventional technology If the recording surface of an optical disc has too many defects or errors that are too large to be corrected, errors cannot be corrected even if a redundant FCC (False Error Detection and Correction Code) is added and all data is recorded. Unable to play properly. For this reason, during recording, immediately after data is written, the data is read out to determine whether it has been correctly reproduced (verify). If the data cannot be reproduced correctly, it is necessary to record the data in another area. Such a device will be explained with reference to FIGS. 6 to 9. FIG. 6 shows a block diagram of the data processing system of the optical disc device. The data processing system consists of a modulation/demodulation unit that modulates data written to the optical disc 1, which is a recording medium, and demodulates read data, and a control unit that controls recording and playback. from a modulation/demodulation control unit 2, an error detection and correction unit 3 that generates an error detection and correction code for each sector, which is the minimum unit of recording, and performs error detection and correction using this code, and an input/output Puffer memory 4 that stores input and output data. configured.

Next, the operation will be explained. First, when recording on the optical disc 1, data of multiple sectors received from external input/output is temporarily stored in the input/output buffer memory 4, and the error detection and correction section 3 detects and corrects errors for each sector, which is the minimum unit of recording. A code is generated, added to the sector, and recorded on the optical disc 1 via the modulation/demodulation control unit 2. Furthermore, when reading data from the optical disk 1, the data flow is reversed and the read data is demodulated by the modulation/demodulation control section 2, and the error detection and correction section 3 demodulates the read data.
Errors are detected and corrected by the input/output buffer memory 4, and data is input/output to/from the outside via the input/output buffer memory 4.

Furthermore, in order to increase the reliability of the data, the recorded data is read out immediately afterward and a verification check is performed. If there is an error in the data read out during this verification, the data of the sector with the error is stored in a spare sector called a replacement sector. Record.

FIG. 7 shows an example of this recording format. In FIG. 7, sectors are broadly divided into user sector areas and spare sector areas, and one track is provided with 10 user sectors and 1 spare sector. In this example, recording is performed in 50 sectors from sector 00 to sector 49,
After verifying 7)-P lid 02 and sector 4
Since a data error has occurred in sector 8, sector 02 is written to a replacement sector adjacent to sector 06 in the same track, and sector 48 is written to a replacement sector adjacent to sector 49 in the same track. FIG. 8 shows this flowchart. Write processing 801 is started, and step 8
Data is written to the user area in step 02. In this case, after writing to 50 sectors from sector OO to 49, the user area is verified in the progressive 803.

As a result of verifying, if there is no sector with an error in writing, the process ends normally (809). If there is a sector with an error, it is written in a replacement sector of the track to which the sector belongs (805), and the result is further verified (806). If there is no error as a result of the verification 807, the process ends normally 8
09, and if an error occurs, the data is written to a new replacement track 808 prepared at a different location.

Next, when reading data written in a replacement sector, taking sector 02 as an example, when reading sector 02, the ECC code (error detection and correction code) added to each sector will detect a data error. Sector 02, which was discovered and recorded as a replacement sector due to a read failure (read NG), is read.

FIG. 9 shows a flowchart in the case of reading, in which read processing 901 is started, user area read 902t
- and determines whether the lead is defective 903, and if it is correct, the process ends normally 908. Further, if there is an error in the read sector, it is determined 904 whether the replacement sector has an age, and if there is no replacement sector, an error 909 occurs. If there is a replacement sector, this replacement sector is read 905. It is determined 906 whether or not there is an error in this spare sector, and if there is no error, the process ends normally 908, and if there is an error, the spare track is read 907.Problems to be Solved by the InventionHowever, with this configuration, There is a problem in that when data in the user sector area that is not recorded in the replacement area becomes unreadable, this data cannot be recovered. In the case of a portable recording medium such as an optical disk, this is carried by the user (operator) K, and during handling,
If there is a scratch or the like on a sector that has already been correctly recorded but has not been alternatively recorded in the replacement sector, a reading failure will occur. This kind of thing occurs not only due to carelessness on the part of the operator, but also due to malfunction of the device.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an optical disc device that can read correct data even from an optical disc in which the recording becomes defective due to scratches or the like after normal recording. shall be.

Means for Solving the Problems In order to achieve the above object, it is sufficient to generate an error detection and correction code for each sector group consisting of a predetermined number of sectors and perform error detection and correction using this code. An optical disk device includes a buffer memory that stores data to be transmitted and received from the outside, and a sector error detection and correction means that generates and records an error detection and correction code for each sector, which is the minimum recording unit of the data, and performs error detection and correction using this code. a sector group error detection and correction means for generating and recording an erroneous detection and correction code for each sector group constituted by a predetermined number of sectors, and performing erroneous detection and correction using this code; and a modulation/demodulation control section for controlling input/output modulation/demodulation and recording/playback control of the sector group error detection/correction means. It is still preferable to provide a correction recording area for each sector group and record an error detection and correction code for each sector group in the correction recording area after recording data for each sector group. Further, a correction recording area is provided for each sector group, and the data of each sector in the sector group is read immediately after writing to check whether it has been written correctly.
The data of a sector with an error exceeding a predetermined standard is recorded in the correction recording area of the sector group to which this sector belongs, and the error detection and correction data for each sector group of this sector group is recorded in the correction recording area of other sector groups. It is a good idea to record the code.

An erroneous 9 detection correction code is generated for each sector by the working sector error detection and correction means, and is added to the data of each sector and recorded on the optical disk, and when reading, errors are detected using this code,
However, if a sector is damaged beyond its ability to be corrected, it cannot be corrected.

When a sector group error detection and correction means generates and records an error detection correction code for each sector group consisting of a predetermined number of sectors and reads it out, if a sector in the sector group is damaged beyond its correction ability. However, it can be corrected by other sectors within the sector group and the false 9 detection correction code of the sector group.

Further, if a correction recording area is provided for each sector group and the error detection and correction code for that sector group is recorded therein, correction can be performed quickly.

A correction recording area is provided for each sector group, and after sector data is written, it is verified. Sectors with errors exceeding the correction capacity are recorded in the correction recording area corresponding to that sector group. Since the error detection and correction code for each sector group is recorded in the recording area, the correction recording area of the sector group where no error sector occurs is effectively used, and the sectors of the sector group corresponding to the correction recording area are damaged after recording. Even if this occurs, it can be restored using the error detection and correction codes of other sectors of the sector group and the sector group.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 to 5.

FIG. 1 is a block diagram of the data processing system of the optical disc device of this embodiment. This data processing system includes a modulation/demodulation control unit 2 that modulates data written to the optical disc 1 and demodulates read data, and a control unit that controls recording and reproduction on the optical disc 1, and a minimum unit of recording. A sector error detection and correction section 3 generates an error detection and correction code for each sector and performs error detection and correction using this code; It is comprised of a track error detection and correction section 5 that performs detection and correction, and an input/output buffer memory 4 that stores input/output data.

Note that the hardware configuration of the track error detection and correction unit 5 has many parts that overlap with the hardware configuration of the sector error detection and correction unit 3, so the hardware of the sector error detection and correction unit 3 may be divided and used. The hardware of this sector error detection and correction section 3 uses a known configuration.

Next, the operation will be explained using FIGS. 2 to 5.

FIG. 2 is a recording format, FIGS. 3 and 4 are a schematic flow diagram of write processing, and FIG. 5 is a schematic flow diagram of read processing.

First, the write process will be explained with reference to FIG.

As shown in FIG. 2, each track is divided into a user sector area and a spare sector area, and a spare track (not shown) is provided in addition to the user sector area. Data is recorded in the user sector area. First, as a write process 301, 50 sectors worth of data as user data is written in the user sector area from sector OO to sector 49 (302). In this embodiment, one track shown in FIG.
Since it is composed of 0 user sectors, 5 tracks worth of data will be written. Next, a verify check 303 is performed on these 50 sectors, and as a result, errors exceeding the correction ability of the error detection and correction code are detected in each sector 304, sector 02 and sector 48, and the data in these sectors is 30 written to alternate sectors of the track
5. Of course, the data written in this spare sector is also verified 306, and if no error is detected, it is 307 and normal termination 313, but if an error is detected, it is 307, which is not shown in FIG. Correct data is written to a replacement track prepared in a completely different area on the same disk (308). This is called replacement track processing, but since this processing is not relevant to this embodiment, further explanation will be omitted. .

For tracks for which no error is detected in the verify 304, it is determined whether one track has been written (309)
If the data has not been written (for example, if 51 sectors of data were initially recorded, only 1 sector's worth of data is recorded on track 05).Normal completion 31
3L, if all of its constituent sectors have been written, such as tracks OO to 04, then a check 310 is performed to see if the replacement sector of that track is being used. The replacement sectors of track 00 and track 04 include sector 02. Since the correct data in the sector 48 has been recorded, the replacement sectors of these tracks are considered used and the process ends normally (313). But track 01
゜02.03 is unused. For these tracks, the error detection and correction unit 5 calculates error detection and correction codes FCC (10, 11...19) using sectors 10 to 19 as data in the case of track 01, for example.
11. This is written as A in the spare sector of track 01. Similarly, FCC (20, 21...29) is written as B in the spare sector of track 02, and ECC (30, 31...29) is written as B in the spare sector of track 03. ...39)
Write as C.

In addition, the work of calculating and recording ECC(S) 311゜3
12 takes time. For this reason, writing operations 301 to 30 to each sector, which are data recording operations on the optical disk 1, are performed.
The operations 309 to 3120 are separated from the operations No. 8 and performed at separate times, resulting in good efficiency for the entire optical disk device.

This case will be explained using FIG. 4.

When the ECC(S'') write process 401 is started, the target tracks, that is, the tracks 01, 0, 2, 03, in which error correction data has not been written in the replacement sector.
One track is read 402 for each track. In this case, the user sectors of these tracks are written 40
3, but in the case described in 309 in Figure 3, I
In some cases, the data for a track has not been written, and in this case, the process moves on to checking the next track.

If the track has already been written, check if the replacement sector of the track is used, and if the track is already used, write the next sector.
Move to Tsuku no Chie 1, unused trunk 01,0
In the case of 2.03, the error detection and correction unit 5: FCC (
10, 11-19), FCC (20, 21...29)
).

Calculate ECC (30, 31...39) and get A for each.

B and C are written to the alternate sectors belonging to the track, and when the FCC(S) for one track is written, the process moves to writing to the next track 407, and when all the tracks have been checked and written, it is called normal end 408. do. If this is done separately from the writing of FCC(S)k data, the optical disk device can operate independently of the external input/output side, generally the host computer, etc., so the host computer is not performing other operations. It becomes possible to write the FCC(S) when the device is not being accessed.

Next, the readout process will be explained with reference to FIG.

Read processing 501 first performs reading 502 of the user sector area, and if the reading is normal, it ends normally 509
do. When an error is detected in reading, a replacement sector of the track to which the sector belongs is read 504, and if reading of this replacement sector results in an error, 505 may generally be alternatively written to the replacement track. Therefore, replacement track processing 510 is entered. However, since this embodiment is not related to track processing, detailed explanation will be omitted. 505 if reading of the replacement sector is completed normally
However, if the data recorded in the replacement sector is a target sector that is a replacement for a sector that cannot be read in the user sector area (506), the process ends normally (509) without any problem. However, if what is recorded in the alternative sector is ECC(S), 507 means that this ECC(S) and this ECC(S'
) is calculated based on the data of other user sectors of the track to which the target sector belongs 508, and the target sector can be corrected by 1. υ Normal end 509 is performed. However, if neither the target correct sector nor FCC(S) is written in the spare sector, the process 507 results in a spare track process 510. If the ECC(S) is written in this manner, it is possible to restore the data in the user area sector even if the data with its error corrected is not recorded in the replacement sector.

In addition, in this embodiment, sector data is verified immediately after writing, and a sector with an error is written to a replacement sector.
FCC(S) is recorded on tracks without errors, but FJC is recorded on all replacement sectors without verification.
C(,S) may be recorded in a replacement sector.If a verified and erroneous sector is recorded in a replacement sector, the normal sector at the time of recording belonging to that track will be
If other sectors are scratched due to subsequent operations, it will not be possible to restore the scratched sector, but if you record FCC(S)t-recording, which sector within that track will be scratched. It can be restored even if .

In this embodiment, the explanation was made as a 1-track IO sector, but
This number of sectors is an example and may be any appropriate number.

Effects of the Invention As is clear from the above explanation, the present invention is a sector group in which a predetermined number of sectors are made into a sector group, an error detection and correction code is generated for all sectors belonging to this sector group, and error detection and correction is performed using this code. By providing the error detection and correction means, even if a sector is damaged due to subsequent causes such as damage due to an erroneous operation after data has been recorded, the sector can be restored.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, FIG. 2 is a diagram showing an example of a recording format, FIGS.
Figure 5 is a flow diagram of the recording process, Figure 5 is a flow diagram of the read process, Figure 6 is a block diagram showing the configuration of a conventional example, and Figure 7 is a flow diagram of the reading process.
The figure shows an example of the recording former of the apparatus shown in FIG. 6, FIG. 8 is a flowchart of the write process of the apparatus shown in FIG. 6, and FIG. It is a flow diagram. l... Optical disk, 2... Modulation/demodulation control unit, 3...
Sector error detection and correction section, 4... input/output buffer memory, 5... track error detection and correction section.

Claims (3)

[Claims] (1) A buffer memory that stores data to be transmitted and received from the outside, and a sector error detection and correction means that generates and records an error detection and correction code for each sector, which is the minimum recording unit of the data, and performs error detection and correction using this code. , sector group error detection and correction means for generating and recording an error detection and correction code for each sector group constituted by a predetermined number of the sectors, and performing error detection and correction using this code; the sector error detection and correction means and the sector group; An optical disc device comprising: a modulation/demodulation control unit that modulates/demodulates input/output of an error detection/correction means and controls recording/reproduction. (2) A correction recording area is provided for each sector group, and after recording data for each sector group, an error detection and correction code for each sector group is recorded in the correction recording area. Optical disc device described in Section 1. (3) A correction recording area is provided for each sector group, and immediately after the data in each sector in the sector group is written, it is read out and checked to see if it has been written correctly, and the data of sectors with errors exceeding a predetermined standard are stored in this sector. The error detection and correction code for each sector group of this sector group is recorded in the correction recording area of the sector group to which it belongs, and the error detection and correction code for each sector group of this sector group is recorded in the correction recording area of the other sector group. The optical disc device according to item 1.