JPH04268262A - Optical disk control device - Google Patents

Abstract

PURPOSE:To greatly reduce the time required of an alternate track processing. CONSTITUTION:A microprocessor 15 houses a flag displaying that the alternate track was searched, a flag displaying that an already written sector is included in the alternate track, and the number of the already written sector (used sector number) in RAM 14. When there is a data error 15 in the sector read out from the optical disk 6 and when the alternate track processing is performed and when the alternate track search flag read out from RAM 14 ON, and when ON/OFF of the substitute track already written flag from RAM 14 is searched and when it is OFF, the microprocessor 15 immediately reports the read-pout error to the host device 1. When it is ON, the used sector number is read out from RAM 14, and when it is 0, a read-out error is reported to the host device 1 and only when it is not 0, the sector on the alternate track is searched.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an optical disc device.

0002

2. Description of the Related Art Conventionally, in this type of optical disk control device that controls an optical disk device, when there is an error in data read from a certain sector of an optical disk storage medium, a sector on an alternative track with the same contents as that sector is read. It is designed to read data from. Conventionally, when performing such alternative track processing, all sectors on the alternative track were read.

0003

Therefore, in conventional optical disc control devices, when a data error occurs and alternative track processing is performed, the processing time for a read command is significantly increased.

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical disc control device that eliminates these drawbacks and significantly reduces the time required for alternative track processing.

[0005]

[Means for Solving the Problems] The present invention is a control device for an optical disk device that checks whether or not a written sector is included in a memory and an alternative track, and sets an alternative track written flag representing the result to the above. a first flag creating means for storing in a memory; and when the first flag creating means stores the flag in the memory, a second flag creating means for storing an alternative track search flag in the memory;
a sector number detection means for checking the number of written sectors included in the alternative track and storing it in the memory as the number of used sectors; The present invention is characterized by comprising an access means for accessing the alternative track and reading data from sectors of the alternative track based on a flag, the alternative track written flag, and the number of used sectors.

[0006]

[Example] Next, an example of the present invention will be described. Figure 1
An example of an optical disc control device according to the present invention is shown in FIG. First, the configuration of this optical disc control device 100 will be explained. Write data transfer circuit 2, write data buffer 3
, the encoding circuit 4, and the modulation circuit 5 are circuits for performing predetermined processing on write data from the host device 1 and outputting the data to the optical disk device 6. The transfer circuit 2 receives data to be written to the optical disk device 6 from the host device 1 and transfers it to the buffer 3. The buffer 3 temporarily holds this data and then outputs it to the next encoding circuit 4. The encoding circuit 4 generates an error detection/correction (ECC) byte based on the received data, and the modulation circuit 5 modulates it into a signal for writing to the optical disk device 6 and outputs it to the optical disk device 6.

A demodulation circuit 8 , an error detection and correction (ECC) circuit 10 , a read data buffer 11 , and a read data transfer circuit 12 perform predetermined processing on read data from the optical disk device 6 and output it to the host device 1 . It is a circuit. The demodulation circuit 8 demodulates the modulated read data from the optical disc device 6. ECC circuit 10
decodes the demodulated data, corrects any errors detected, and outputs the results to the buffer 11. The buffer 11 temporarily holds the data and then outputs it, and the transfer circuit 12 receives the data from the buffer 11 and transfers it to the host device 1.

Microprocessor 15 and RAM 14
plays a central role in the optical disc control device 100 of the present invention, and the RAM 14 stores an alternative track search flag, an alternative track written flag,
The microprocessor 15 generates these flags and the number of used sectors, and performs alternative track processing based on these flags and the number of used sectors. The device interface circuit 13 and host interface circuit 16 are used by the microprocessor 15 to exchange control signals with the optical disk device 6 and host device 1, respectively. Further, the ID detection circuit 9 detects the track number and sector number designated by the microprocessor 15 from the read data after demodulation,
The results are given to the ECC circuit 10 and the buffer control circuit 7. Buffer control circuit 7 controls buffers 3 and 11 based on instructions from microprocessor 15.

The optical disk storage medium of this optical disk device 6 is divided into a predetermined number of zones, and an alternative track is provided for each zone.

The format of sectors on the optical disk storage medium of the optical disk device 6 is as shown in FIG. A sector consists of an ID section 42, a gap 35, and a data section 43, and the ID section 42 includes a PLL synchronization byte 30, an ID synchronization byte 31, a track number 32, a sector number 33, and an error detection (CRC) byte 34.
It is made up of. The data section 43 includes a PLL synchronization byte 36, a data synchronization byte 37, a track number 38,
Sector number 39, data 40, and ECC byte 4
1. Here, in the original sector, the track number 38 and sector number 39 of the data section 43 are I
The track number 32 and sector number 33 of the D section 42 match, and in the alternative sector and sectors on the alternative track, the track number 38 and sector number 39 of the data section 43 are the track number of the ID section 42 of the original sector. 32 and sector number 33.

Next, the operation of alternative track processing when reading data will be explained using the flowcharts shown in FIGS. 3 to 6.

The processing of each step in the flowchart is as follows. Flowchart in Figure 3 301 Read original sector 302 Is there an error sector? 303 Read the alternative sector 304 Check whether there is a sector corresponding to the error sector in the alternative sector 305 Is there a sector? 306 Replace the data in the error sector with the data in the matched alternative sector 307 Transfer the specified number of sectors of data to the host device 308 Alternative track search flag on? 309
Alternative track written flag on? 310 Number of sectors used in that zone = 0? Flowchart in Figure 4 311 Read sector of alternate track 312 Written? 313 Compare the track number of the read sector and the track number of the error sector 314 Match? 315 -1 the number of used sectors in the zone 316
Compare the sector number of the read sector and the sector number of the error sector 317 Match? 318 Number of sectors used in that zone = 0? 319
Flowchart of FIG. 5 for replacing data in an error sector with data in a matching sector 320 Reading sector on alternate track 321 Already written? 322 Turn on the written flag 323 Add 1 to the number of used sectors of the zone according to the track number of the sector of the alternative track 324 Compare the track number and sector number of the sector of the alternative track with the track number and sector number of the error sector 325 Match? 326 Flowchart of FIG. 6 for replacing data in error sector with data in matching sector 327 Last sector of alternate track? 328 Turn on the alternative track search flag 329 Is there a sector? In FIG. 1, when the microprocessor 15 receives a read command from the host device 1 via the interface circuit 16, it instructs the optical disk device 6 via the interface circuit 13 to read a predetermined number of original sectors. As a result, the optical disk device 6 reads data from the original sector (step 301) and outputs it to the demodulation circuit 8. The demodulation circuit 8 demodulates the received data and outputs it.
The CC circuit 10 decodes data for each sector to detect an error, and if the error is correctable, performs the correction. EC
Data from the C circuit 10 is output to the buffer 11 and is temporarily held in the buffer 11.

When data has been read from a predetermined number of original sectors, the microprocessor 15 reads error information for each sector from the ECC circuit, and checks whether there is any sector containing uncorrectable error data (step 302).
.

As a result, if there is no such error sector, the microprocessor 15 outputs the control circuit 7,
Data from a predetermined number of sectors held in the buffer 11 is output. The transfer circuit 12 receives the data and transfers it to the host device 1 (step 307), and the reading of data from the optical disk device 6 is completed.

On the other hand, if there is an error sector, the microprocessor 15 issues an instruction through the interface 13 to read data from the alternative sector of the optical disc device 6 (step 303). Then, in order to check whether the read alternative sector matches the error sector, the track number and sector number of the data part of the alternative sector are compared with the track number and sector number of the data part of the error sector (step 304 , 305). the result,
If the compared numbers match, the control circuit 7 is controlled to replace the data in the error sector with the data in the alternative sector in the buffer 11 (step 306), and the process proceeds to step 307.

In step 305, if the compared numbers do not match, the microprocessor 15 will perform alternative track processing. That is, the microprocessor 15 first searches for an alternative track from the RAM 14.
The flag is read and its on/off status is checked (step 308). As a result, when it is off, it means that the alternative track has not been searched yet, and the optical disc device 6 is instructed to read the sector on the alternative track (step 320). Then, it is checked whether the read sector has been written (step 321), and if it has not been written, it is checked whether the sector is the last sector of the alternative track (step 327), and if it is not the last sector, the next sector is checked. sector (step 320). When the read sector has been written, the alternative track written flag is turned on and stored in the RAM 14 (step 322). Then, based on the track number of the data part of this written sector, the number of used sectors in the alternative track of the zone containing that track is stored in the RAM.
14, add 1 to it, and store it in the RAM 14 again (step 323).

Thereafter, the track number and sector number of the data portion of the written sector are compared with the track number and sector number of the error sector (step 324).
, if they match (step 325), the control circuit 7 is controlled to replace the data of the error sector with the data of the written sector in the buffer 11 (step 3
26). Note that if there is a mismatch, step 326 is skipped and the process proceeds to step 327. Having read all sectors on the alternate track in this manner, microprocessor 15 turns on the alternate track search flag and selects R.
The data is stored in AM14 (step 328).

When the microprocessor 15 completes the search for the alternative track, it checks whether there is a sector on the alternative track that corresponds to the error sector (step 329).
, if YES, the control circuit 7 is controlled and the buffer 1 is
Data from a predetermined number of sectors held at 1 is output. The transfer circuit 12 receives the data and transfers it to the host device 1 (step 307), and the reading of data from the optical disk device 6 is completed. On the other hand, in the case of NO, the occurrence of a reading error is reported to the host device 1.

In step 308, an alternative track search is performed.
If the flag is on, the microprocessor 15 reads the alternative track written flag from the RAM 14 and checks whether it is on or off (step 309).
). If it is off, there will be no written sectors on the alternate track, so the microprocessor 15
reports to the host device 1 that a reading error has occurred. On the other hand, if it is on, there is a possibility that a sector corresponding to the error sector is included in the alternative track. reads the number of used sectors of the substitute track from the RAM 14;
Check whether it is 0 (step 310). When the number of used sectors is 0, it means that there are no written sectors on the alternative track, so the microprocessor 15
reports the occurrence of a read error to the host device 1.

On the other hand, when the number of used sectors is one or more, the microprocessor 15 performs alternative track processing. That is, the microprocessor 15 first instructs the optical disk device 6 to read a sector on the alternative track (step 311). Then, it is checked whether the read sector has been written or not (step 312), and if it has not been written, the process returns to step 311 and the next sector is read, and if it has been written, the track number of the data section of that sector is The track number of the error sector is compared (step 313).

As a result, if there is a mismatch (step 3
14) Return to step 311 again and repeat the above steps, and if they match (step 314), the number of used sectors of the alternative track provided for the zone containing the track with the track number of the error sector data section is determined. R
After reading from AM14 and subtracting 1, it is read again from RAM14.
Store in.

Next, the microprocessor 15 compares the sector number of the data portion of the written sector with the sector number of the data portion of the error sector (step 316), and if they match (step 317), the control circuit 7 and replaces the data in the error sector with the data in the written sector in the buffer 11 (step 31).
9) If they do not match, the number of used sectors of the alternative track in that zone is read from the RAM 14, and it is checked whether it is 0 or not (step 318). As a result, when the result is 0, it means that there is no sector to be replaced with an alternative track, so the microprocessor 15 reports the occurrence of a read error to the host device 1. On the other hand, when the result is 1 or more, the process returns to step 311 and the next Read the sector, step 312
Repeat the following operations.

[0023]

As explained above, in the optical disc control device of the present invention, alternative tracks and sectors on the alternative tracks are managed by the alternative track search flag, the alternative track written flag, and the number of used sectors. When performing alternative track processing, it is possible to quickly determine whether or not there is a target sector on the alternative track and to search for it, and as a result, the time required for alternative track processing can be significantly shortened.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of an optical disc control device according to the present invention.

FIG. 2 is a format diagram showing a sector configuration of an optical disc storage medium in an optical disc device controlled by the optical disc control device of FIG. 1;

FIG. 3 is a flowchart showing the operation of the optical disc control device in FIG. 1;

FIG. 4 is a flowchart showing the operation of the optical disc control device in FIG. 1;

FIG. 5 is a flowchart showing the operation of the optical disc control device in FIG. 1;

FIG. 6 is a flowchart showing the operation of the optical disc control device in FIG. 1;

[Explanation of symbols]

2 Write data transfer circuit 3 Write data buffer 4 Encoding circuit 5 Modulation circuit 7 Buffer control circuit 8 Demodulation circuit 9 ID detection circuit 10 Error detection/correction circuit 11 Read data buffer 12 Read data transfer circuit 13 Device interface circuit 14 RA
M15 microprocessor

Claims (1)

[Claims] 1. In a control device for an optical disk device, a first flag for checking a memory and whether or not an alternative track includes a written sector, and storing an alternative track written flag representing the result in the memory. creating means; a second flag creating means for storing an alternative track search flag in the memory when the first flag creating means stores the flag in the memory; sector number detection means for checking the number of written sectors and storing it in the memory as the number of used sectors; the alternative track search flag, the alternative track written flag stored in the memory, and the number of used sectors; 1. An optical disc control device comprising access means for accessing said alternative track and reading data from sectors of said alternative track based on said alternative track.