JPH02312069A - Optical disk recording system - Google Patents

Abstract

PURPOSE:To obtain an optical recording system capable of correcting an error even when an optical disk has a failure by recording data to be relevantly recorded to plural optical disks in their individual different addresses. CONSTITUTION:The optical disks 4 are loaded into disk driving devices 11, 12..., and the contents of a file name recording area 4a, a number recording area 4b and a recording mode specifying area 4c are read by a control device 2. Whether using purposes are fitted or not is decided by a host computer 3 with the contents of the areas 4a. On the other hand, which of the devices 11, 12... is loaded with which of the numbers of the disks 4 is specified by the device 2 with the contents of the areas 4b. Which disk is loaded into which of the devices 11, 12... is specified by a reproduced data from an optical disk recorded with a check symbol generating regulation of an error correction code and a check symbol. Thus, when the addresses are dispersedly recorded, an error to be mixed into a data is restricted to one disk, so that the error correction can be carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical recording system that uses an optical disk (including a magneto-optical disk) as a recording medium.

[Conventional technology]

Some magnetic disks achieve high transmission rates by rotating multiple disk drives synchronously.

For example, Nikkei Electronics December 28, 1987
There is a system shown on page 48.

On the other hand, optical discs have been put into practical use as large-capacity information recording media. In order to utilize this characteristic more effectively, an array-type optical recording system has been proposed in which a plurality of disk drives are combined to operate as if they were one large-capacity disk drive.

[Problem to be solved by the invention]

In such optical recording systems, there is a possibility that some optical discs may be lost, damaged, or partially destroyed.
Measures against this are essential.

As having taken this measure, the applicant of the present application
No. 54153 is proposed. This optical recording system
By recording data in a distributed manner on multiple optical disks and recording error correction code check symbols on some of the optical disks, some of the optical disks may be lost, damaged, or partially destroyed, or the optical disk drive may malfunction. The configuration is such that it can be operated without any problems.

When a large number of optical discs are used, they are often created simultaneously.

If there is a problem with the original (master) or standby of an optical disc, the same problem will appear on the optical disc (that is, the replica), so when using a large number of optical discs as described above, it is possible to avoid problems caused by problems with the master or standby. If it exists on any optical disc, it is likely to exist on other optical discs as well.

An object of the present invention is to provide a recording method that can maintain high appendability even under such circumstances.

[Means to solve the problem]

In the recording method of the present invention, the addresses of a plurality of optical discs on which data is recorded in a distributed manner are made to be different from each other.

[Effect]

Defects caused by defects in the master disc or stamper appear at the same address on the optical disc. Therefore, when distributed recording is performed at different addresses, the errors that may be mixed into the distributed recorded data are limited to one disk, and it is therefore possible to correct the errors using an appropriate method.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on drawings showing embodiments thereof.

FIG. 1 is a block diagram of a system for implementing the optical recording method according to the present invention.

In the figure, reference numerals 11, 12, . . . , 20 are optical disk drive devices, which record data given from the control device 2 on an optical disk, or reproduce data recorded on an optical disk. 3 is a host computer, which provides data to be recorded to the control device 2 or instructs the data reproduction.

FIG. 2 shows the main part of the recording format of the optical disc 4, including a file name recording area 4a where information identifying a data file constituted by recorded data is recorded, a number recording area 4b where the number of the optical disc is recorded, and a recording area 4b where the number of the optical disc is recorded. It is provided with a form specific area 4C.

The number of the optical disk may be a system in which only one number is the same in the entire system, or a system in which there are multiple numbers in the same system.

In the recording format specific area 4C, it is possible to determine whether the entire recording area of the disc is used or a part of the recording area is used. The optical disc can be used as a high-capacity recording medium, or conversely, the optical disc can be used as a low-capacity recording medium by using some specific areas while recording and reproducing at high speed.

In optical disc recording, when data is recorded on the entire surface,
Although the capacity per disk becomes larger, it is necessary to seek all the tracks, and the seek time becomes longer. On the other hand, when only some tracks are used, the distance to seek becomes shorter, so the storage capacity per sheet becomes smaller, but the seek time becomes shorter. Codes for identifying these recording modes are recorded in the recording format specifying area 4C.

In this system, an optical disc on which a specific number, for example 9°10, is recorded in the number recording area 4b records only check data generated from data recorded on other optical discs, that is, check symbols of error correction codes. do.

The operation of the system as described above is as follows. The optical disc has a file name recording area 4a, a number recording area 4b,
The operation differs depending on whether the recording format specific area 4C is recording or not. If these areas 48 to 4C are not recorded, 10 copies are recorded during formatting of the optical disc. The ID section is information that identifies a set of a plurality of optical discs, and is recorded in, for example, the file name recording area 4a. Assuming that the ID section has already been recorded, first, before starting the system, the optical disk 4 is loaded into the optical disk drive device 11, 12, . . . . In this case, any optical disc may be loaded into any optical disc drive device 11, 12, . . . . Upon system startup, the control device 2 reads the contents of the file name recording area 4a, number recording area 4b, and recording format specific area 4C. The host computer 3 determines whether or not an optical disk matching the purpose of use has been selected and loaded based on the contents of the file name recording area 4a.

On the other hand, the control device 2 specifies which optical disk drive device 11, 12, . . . has which numbered optical disk 4 loaded based on the contents of the number recording area 4b.

As will be described later, each optical disk drive device 11, 12, .
It is possible to specify which optical disc is loaded in the disc. If there are 10 optical disk drive devices as in this embodiment, 8 are drive devices for recording and reproducing information,
Two drive devices record and reproduce test symbols.

However, the drive device for recording and reproducing information and test symbols is not fixed, and the loaded optical disc serves as both a drive device for information and a drive device for test symbols. As an error correction method, for example, as shown in FIG. 3, there is a method using a Reed-Solomon code. That is, the 8 bits of data recorded on the optical disks numbered 1 to 8 are expressed as one unit, and this is expressed as ai (i=1 to B), and the element on GF (2'') is expressed as α, and the parity is as follows: P
, ,P, is calculated.

od2 Record these P, , P, respectively on the optical disk numbered 9.10. In other words, the check symbols p, , p of this error correction code
z is composed of multiple optical discs,
Its Hamming distance is 3. In other words, two optical disks are provided for recording the test symbols p+ and pg, respectively.

This error correction also makes it possible to identify the correspondence between the recording/reproducing drive device and the optical meter isk. That is, at the stage when the optical discs are loaded, it is assumed that each optical disc is loaded into a preset optical disc drive. Next, a bundle of α is created based on the assumed optical disc-optical disc drive relationship, and error correction (described later) is performed. However, if the actual loading state of the optical disc is different from the assumed one, error correction cannot be performed and a syndrome occurs. If a syndrome occurs, error correction is performed again assuming a different loading state. In this way, the assumption of the loaded state is sequentially changed and the same process is repeated until the correct state is encountered. In this way, the correct optical disc loading state can be found. When recording new data, since there is already a recorded part, play that part, use the same procedure as described above to find the correspondence between the optical disc and the optical disc drive, and record the data on the correct optical disc. be able to. By doing so, it is also possible to specify the number of the optical disc without providing the number recording area 4b.

FIG. 4 is a block diagram showing an example of the control device 2. As shown in FIG. The control unit W2 has a buffer RAM (
RAMI, RAM2...RAM10), the data to be recorded by each optical disk drive device 1112... is once stored here, and then transferred to each optical disk drive device, and during playback, each optical disk drive device 1L12...・
The data played back is temporarily stored here. Encoding and decoding of the error correction code are performed in another RAM (RAMII), central processing unit CPU2, read-only memory ROM2, and Galois logic unit (GLU). Data to be encoded and decoded is once stored in RAMII and then calculated using Galois logic unit (GLU).

The calculations are controlled by the central processing unit 1cPU2.

Firmware for control and instructions for α are stored in a read-only memory ROM2. host computer 3
Data is exchanged with the interface 5 through the interface 5.

Data from host computer 3 is stored in another RAM (R
AM12) and then transferred to RAMII.

Conversely, when transferring playback data to the host computer 3, it is stored once and then transferred to the host computer 3.

These controls are performed by another central processing unit CPUI, and the firmware for this is implemented by another read-only memory ROMI.
Store it in.

In such a system of the present invention, when recording data given from the host computer 3, the control device 2 adds check data to the data input from the host computer 3 to the central processing unit CPU2. RAMII.

(Galois Logic Unit) GLU is used to add to the data and send it to the optical disk drives 11, 12, . . . , as well as control signals necessary for controlling the optical disk drives 11, 12, . At this time, the optical disk drive device to which the data should be sent is specified by the recording data in the number recording area 4b or by the above-mentioned error correction repetition method.

The optical disk drive device 1ZIL12... records the data sent in this manner on the optical disk.

On the other hand, upon reproduction, in accordance with instructions from the host computer 3, the control device 2 sends a signal instructing the optical disk drive 1L12... in which the corresponding optical disk 4 is loaded to reproduce, and a signal indicating the position where the data to be reproduced is recorded. Emit a physical address signal or a logical address signal. This allows the required data to be reproduced.

Next, the data recording method of the present invention will be explained in comparison with a conventional method. In a conventional optical disc, data is recorded in a predetermined sector and then reproduced. At this time, if the difference between the data to be recorded and the reproduced data is greater than a predetermined standard, the data is re-recorded in a spare sector prepared in advance for each track, that is, a replacement sector. The recording to this spare sector is also played back and inspected, but if there are many errors in this recording, a spare track prepared in advance,
In other words, recording is performed again and again on the alternate trunk.

The replacement track is also used when recording to the replacement sector occurs again in the l track.

On the other hand, in the system of the present invention, the above-mentioned replacement sector,
It is also possible to always record check data on one or more specific optical discs without providing anything similar to a replacement track. FIG. 5 is a conceptual diagram showing an example of the recording method, in which the recording unit is 8 bytes, ten optical disk drives are used, and the optical disks of two of the drives are used for recording check data. . Figure 5 (
As shown in al, it is assumed that 8 bits (1 byte) of MSB-LSB data exist from the first byte to the eighth byte. Then, as shown in FIG. 5(b), each byte contains two parity symbols (first parity symbol Pl,
A second parity symbol pz) is created.

This creation is based on formula (1) and +21 above. This first ~
Optical disk 4 on which all MSBs of the 8th byte are recorded with numbers ■
is sent to the optical disc drive in which the disc is loaded.

Also, all the data of the second bit of the first to eighth bytes are simultaneously sent to the optical disk drive device in which the optical disk 4 on which the number ``2'' is recorded is loaded. Thereafter, the data of the first to eighth bytes are similarly sent to the optical disk drive device loaded with the optical disk of each number.

The 8-bit data of the first parity symbol PI and the second parity symbol P2 are respectively ■.

The optical disc with the number [phase] is sent to the optical disc drive device loaded with it. The data sent to each optical disk drive device will be recorded on the optical disks loaded respectively.

FIG. 6 is a flowchart of the processing procedure when recording data. When an optical disc is loaded (121) and the optical disc drive devices 11, 12, etc. are started, the ID section is first read by each drive device 11, 12, etc. (121).
22).

This is transferred to RAM1-RAM10 (#23).

Central processing unit CP[11 checks this ID section (#24)
, if they are not the same, this is reported to the host computer 3 (1125).

If they are the same, each optical disk drive device 11, 12...
・Reads or determines the number of the optical disc loaded in (t126).

FIG. 7 is a diagram showing data storage areas of RAMI to RAM10. Apart from the area for storing data, there is also an area for storing identification data read from the file name recording area 4a + number recording area 4b and recording format specifying area 4c (marked in the figure).
a, 4b, and 4c) are provided.

When the optical disc is loaded, the optical disc drive reproduces the identification data and transfers it to RAMI to RAM10.

Is the central processing unit CPt1l l? The identification data stored in the identification data area in AM1 to RAM10 is read to determine which optical disc is loaded into which optical disc drive.

Data to be recorded on the optical discs loaded in the ten optical disc drive devices 11, 12, . . . is stored in RAMII and then in RAMI to RAM10. R
AMI~I? AM10 is assigned to each of the 10 optical disk drives. On the other hand, the accumulation in RAMII is also 1
Addressing is performed separately for each 0 optical disc. Therefore, when the optical disk loaded in each optical disk drive device can be determined, the address of RAMII, which stores the data to be transferred to each of RAMI to RAM10, is set (1127). After making this setting, the data to be recorded is then transferred from the host computer 3 to the RAM 12 (1128). Furthermore, this data is transferred to the RAM II (1129), and the data stored in the RAM II is encoded with an error correction code using the Galois logic unit (GLU) and the central processing unit CPU2 (1130). Then, according to the address set earlier, transfer the data of RAMII to each of RAMI~RAMl0 (+131)
. The data is sent from each RAMI to RAMl0 to the optical disk drives 11, 12, . . . and recorded in the data area of the optical disk 4 loaded in each.

FIG. 8 is a schematic diagram showing the recording areas of optical disks ■ to [phase]. Data interleaved using the method shown in FIG. 5 and its test symbols are recorded at different addresses (physical addresses) on each optical disk. Ru. This can be done by physically shifting the drive position of the optical disc in the optical disc drives 11, 12, . . . , 20. For example, the rotational phase may be shifted by one sector for each optical disk drive.

Another method is to leave the rotational phase in the optical disc drive as it is, but to delay the recording time by the time required to rotate one sector.

Although the present invention can be carried out by making the tracks and sectors of each optical disk completely different, or by selecting and recording them unrelatedly, in the case of the method described above, the writing trunk is made common and the writing sectors are related. It has the advantage of being easy to control.

Furthermore, in the case of the first method, since simultaneous recording is possible, the time required for recording can be shortened accordingly. Furthermore, during reproduction, all optical discs can be reproduced simultaneously, and data can be easily organized.

Note that in the case of the second method, the timing control of recording and reproduction may be performed by the control device 2.

FIG. 9 shows an example of another recording method, in which the first parity symbol Pl+second parity symbol P2 is created from all bytes as shown in FIG. The second byte is the optical disk with the number ■, the first parity symbol is the optical disk with the number ■, and the second parity symbol is the optical disk with the number [phase]. Of course, the information is recorded at different addresses on each optical disc.

Furthermore, during playback, the original data is restored using the reverse procedure to the above-mentioned recording procedure. That is, the data reproduced from each optical disk drive device is associated with the number of the optical disk loaded in each device, and the data is organized byte by byte using the logic opposite to interleaving as shown in FIG. 5 or FIG. 9. Get the data. When restoring this data, that is, decoding, error correction is performed using a Reed-Solomon code on GF(2').

That is, as shown in FIG.
If 9 + r 10, the syndrome So is determined by the following formula.

Calculate S.

So = Σr.

S+ ='E ri αi (α+o= 1) If there is no error, ri = a □, so 5o = s, = 0, but if there is an error on the i-th optical disk, 5
0=0, but S O=e i . Therefore S+/
This α is obtained by finding So=α.

Since is a value unique to each optical disc, it is possible to identify the optical disc and correct errors. Note that if αi is a value other than the value assigned to each optical disk, it is assumed that simultaneous errors have occurred on two or more optical disks, and error correction is not performed and only the occurrence of simultaneous errors is detected.

Even in this case, if one optical disc can be identified using the error pointer, erasure, etc., it is possible to identify the other optical disc, and therefore to correct errors in both optical discs.

FIG. 11 is a flowchart showing the processing procedure for reproduction and error correction. When the optical disk 4 is loaded (#I) and the optical disk drive devices 11, 12, . . . are driven, the ID section is first read by each drive device 11, 12, . . . (#2). This is transferred to RAMI to RAM10 (#3).

The central processing unit CPt1l checks this TD section (+14)
, if they are not the same, this is reported to the host computer 3 (#5). If they are the same, each optical disk drive 1
The number of the optical disc 4 loaded at 1° 12, . . . is read or determined (#6). The playback data from the 10 optical disk drives 11, 12, etc. is stored at a predetermined RA.
It is accumulated in MI~RAMl0, but this RAMl-RA
The accumulated data of Ml0 is transferred to and stored in each area of RAMII allocated according to the number of the optical disk. In step #7, address settings for this purpose are performed. Each optical disc drive bag on top like this? &11.12...
The reproduced data is temporarily stored in RAMI to RAM10, and transferred from there to the set address of RAMII (#8). Then, the above-mentioned calculations are carried out by the central processing unit cpυ.
2 and the Galois logic unit GLU, and if there is an error, it is corrected (#9). The corrected or correct data is then transferred to the RAM 12 (1110) and further transferred to the host computer 3 via the interface 5 (#11).

In the above embodiment, the data in one sector (760 bytes) was distributed and recorded in byte units on eight optical disk drives, but it is also possible to record each sector on a separate optical disk drive. .

FIG. 12 is an explanatory diagram thereof. Arrange the data from the first sector to the eighth sector shown in (a) as shown in (b),
Create a first parity symbol and a second parity symbol. For example, if the error correction code to be used is GF (2"), the first byte of each sector is combined to create the first byte data of the parity symbol sector. Similarly, parity symbols are created for the next byte and subsequent bytes. .1st
Data from sector to 8th sector and data from 1st sector to 8th sector. Second parity symbols are recorded in different sectors of the optical discs 1 to 10.

In the case of the recording method of the present invention as described above, the error correction ability is improved, and recording is performed simultaneously instead of the conventional process of recording, reproducing inspection, rerecording (reproducing inspection), and rerecording. Increases the speed of data transfer. Further, each optical disk does not require a replacement sector or a replacement trunk. Even if an optical disk for recording check data is required, the capacity of the system as a whole can be further increased.

In addition, since there is always a disk on which check data is recorded, even if the recorded data on the optical disk loaded in any optical disk drive is destroyed, or if any optical disk is lost, the data cannot be restored. It is possible. this.

Restoration of data is possible both on the optical disc on which check data is recorded and on other discs.

In the present invention, data to be distributed and recorded is recorded at different addresses on each optical disk, so even if there is a problem caused by the master or stamper at the same address or sector on multiple optical disks, erroneous data will only be recorded on one disk. Error correction or data restoration is possible because the error correction or data restoration is only performed on the optical disc.

In the above embodiment, a test symbol of an error correction code with a Hamming distance n=3 was created and recorded on two optical discs, but a test symbol with a larger Hamming distance is recorded on three or more discs. It goes without saying that if the information is recorded on an optical disc, the error correction ability will be further improved.

〔Effect of the invention〕

According to the present invention as described above, it is possible to realize an optical recording system capable of error correction even when an optical disc has a defect caused by the master disc or the standby disc.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a system for implementing the recording method of the present invention, Fig. 2 is an explanatory diagram of the format of an optical disk, Fig. 3 is an explanatory diagram of check data, and Fig. 4 is a block diagram showing a control device. 5.9 is a conceptual diagram showing an example of the recording method in the system of the present invention, FIG. 6 is a flowchart showing the procedure during recording, and FIG. 7 is a diagram showing RAMI to RAM10.
8 is a conceptual diagram of the recording method of the present invention,
Figure 10 is an explanatory diagram of error detection and correction of reproduced data.
FIG. 1 is a flowchart showing the procedure during reproduction, and FIG. 12 is an explanatory diagram showing another recording method. lL12...Optical disc drive device 2...
IJ? ill device 3... host computer 4...
- Optical disc In the figures, the same reference numerals indicate the same or equivalent parts. Agent Masuo Oiwa 1 Figure 2 Figure 2 Variation (a) Funeral 5 (b) Figure 6 Figure 7 (a) Figure 12

Claims (1)

[Claims] (1) A method for recording data across a plurality of optical disks loaded in each of a plurality of optical disk drives, characterized in that data to be recorded in association is recorded at different addresses on each of the plurality of optical disks. recording method.