JPH07169204A - Information recording and reproducing device - Google Patents

Abstract

PURPOSE:To efficiently use a recording capacity of a disk even in the case of no information to be recorded in a vendor unique area by deleting data of a fixed value from output data from an error correction circuit at the time of recording user data and inserting the data of the fixed value into reproducing data at the time of reproducing. CONSTITUTION:The vendor unique area (VU) of 4 bytes is added to the user data DT0-DT511 of 512 bytes inputted from the outside of the optical disk device 1 by an error correction circuit 3. A vendor has no information to be recorded together with the user data, and the fixed value 00H is prepared as the data of the VU. These data together with error detection codes CRC0-CRC3 of 4 bytes are interleaved into five correction groups. Error correction codes EC0,0-EC4, 15 of 16 bytes are added to five code groups by the circuit 3 to be outputted to a data transfer circuit 4, and data other than the data of the fixed value of the VU are outputted to a recording and reproducing circuit 5 to be recorded. Then, the data is read out of a disk 2 and transferred to the circuit 4 by the circuit 5. Data of 00H is inserted into the user data after DT511 by the circuit 4 to be outputted to the circuit 3, and after error correction, the data is outputted to the outside of the device 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rewritable type, a read-only type, a one-time write type information recording / reproducing apparatus.

[0002]

2. Description of the Related Art Conventionally, in an information recording / reproducing apparatus called a so-called optical disk apparatus, a plurality of tracks are concentrically or spirally formed on the surface of a disk medium, and the tracks are further divided into a plurality of sectors. Recording and reproducing user data.

In an optical disk device which may handle numerical data as user data, it is usually required that the error rate be ^10-12 or less. Thus, the optical disk has a high and 10 ^-6 to 10 ^-4 bit error rate as compared with a magnetic disk or magnetic tape, it must be used error correction scheme to an error of 10 ^-6 to 10 ^-4 to 10 ^{@ 12} or less There is.

For this reason, the optical disc apparatus adopts an error correction system which uses an error correction code such as a Reed-Solomon code or a BCH code, and makes an error correction of a large number of words included in this block with a large number of words as one block. There is.

An example of the error correction method in the conventional optical disc device shown in FIG. 2 will be described with reference to FIG.
This is the ISO 90mm magneto-optical disk standard 512
It is in byte format. First, the optical disk device 20
The case where user data is recorded on the disk medium 201 at 0 will be described below.

The error correction circuit 202 adds a 4-byte vendor unique area VU to 512-byte user data DT0 to DT511 input from the outside of the optical disk device 200. The vendor unique area is
This is an area where the manufacturer (vendor) records the information that the manufacturer wants to record together with the user data.

Further, the error correction circuit 2 is used during data reproduction.
The user data corrected in 02 and the vendor unique area are 4-byte error detection codes CRC0, CRC1, CRC2, and CRC3 that are error detection codes for checking whether or not the correct area is truly correct. Five correction sequences (code sequence 0
~ 4), and are arranged vertically as rows of 5 bytes each as shown in FIG.

The error correction circuit 202 adds 16-byte error correction codes EC0, 0 to EC4, 15 generated from the user data of the five code sequences, the data of the vendor unique area, and the error detection code to each code sequence. Then, each column is sequentially output to the recording / reproducing circuit 203 from the first column of the code sequence 0.

The recording / reproducing circuit 203 records the data output from the error correcting circuit 202 in a designated sector on the surface of the disk medium 201 via the head 204. In this way, the user data is divided into several groups in units of bytes or bits, error correction codes are generated in units of groups, and then the order is rearranged and recorded, which is called interleaving.

In interleaving, a large burst error of several tens of bytes or more existing on the surface of the disk medium can be converted into a small random error of about 1 or 2 bits. It becomes possible to correct the burst error.

Since the vendor unique area is necessary also for equalizing the number of bytes of the five code sequences, a fixed value such as 00H or FFH is set when the vendor does not want to record the user data together with the user data. Will be recorded.

Next, the case where the user data is reproduced from the sector of the disk medium 201 in the optical disk device 200 will be described. The recording / reproducing circuit 203 reads data from a designated sector on the surface of the disk medium 201 via the head 204 and transfers it to the error correction circuit 202.

In the error correction circuit 202, the data transferred from the upper recording / reproducing circuit 203 is rearranged once again in the order of the five code sequences shown in FIG. 3 (this is called deinterleaving), and each of the five code sequences is arranged. Use to correct the error. After that, the error detection code is used to check whether the corrected user data and vendor unique area have been corrected correctly.
The reproduction data is output to the outside of the optical disc device 200.

[0014]

However, in the conventional technique as described above, even if the vendor does not have the information to be recorded together with the user data, the vendor unique area must be provided for the sake of the error correction method.
Therefore, when recording data on the disk medium, unnecessary information (constant value) in the vendor unique area is also recorded, and the number of bytes in one sector increases accordingly, and user data is recorded on the surface of the disk medium. There was a problem that the storage capacity for use became small.

It is an object of the present invention to solve the above problems and to obtain an information recording / reproducing apparatus which can efficiently use the storage capacity of a disk medium even when there is no information to be recorded in the vendor unique area. To do.

[0016]

In order to achieve the above object, in the information recording / reproducing apparatus according to the first aspect of the present invention, the user data of the sector is formed by dividing a track on the surface of the disk medium into a plurality of sectors. In the information recording / reproducing apparatus for recording / reproducing, at the time of recording the user data, the user data and the constant value data are divided into a plurality of groups, and an error correction code is generated for each group, and then output. When reproducing the user data, the data reproduced from the sector is error-corrected by the error correction code in the group unit, and an error correction circuit that outputs the user data when the user data is recorded. Data is recorded in the sector through the head and read from the sector through the head when reproducing the user data. A recording / reproducing circuit that outputs the reproduced data that has been output to the error correction circuit; and a recording / reproducing circuit that is provided between the error correction circuit and the recording / reproducing circuit and that is included in the data output from the error correction circuit when the user data is recorded. And a data transfer circuit for deleting the constant value data and inserting the constant value data into the reproduction data output from the recording / reproducing circuit when reproducing the user data.

[0017]

According to the present invention, when user data is recorded in sector units, the error correction circuit divides the user data and constant value data into a plurality of groups, generates error correction codes for each group, and then outputs them. , Among the data output here, a certain value data is deleted by the data transfer circuit, and then recorded by the recording / reproducing circuit to the sector through the head, and at the time of user data reproduction, the sector is recorded through the head. Information recording in which constant value data is inserted into the data reproduced by the reproducing circuit by the data transfer circuit, and the reproduced data in which the constant value data is inserted is error-corrected by the error correction code in the error correction circuit in the group unit. It is a playback device.

According to the present invention, with the above configuration, the constant value recorded in the vendor unique area when the vendor does not have the information to be recorded together with the user data is deleted when the user data is recorded. The problem that the storage capacity of the disk medium is reduced is solved.

Further, during reproduction of user data, the reproduction data is transferred to the error correction circuit after the fixed value deleted during recording is inserted. Error correction is performed by the error correction method using.

[0020]

EXAMPLES The present invention will be described below with reference to examples. FIG. 1 is a schematic configuration diagram of an interleave correction type optical disc apparatus according to the present embodiment. The error correction method here is the same as that shown in FIG. The error correction method used in the present invention is not limited to this, and is effective for all error correction methods that use both error correction code and interleave.

First, the case where user data is recorded on the disk medium 2 in the optical disk device 1 will be described. The error correction circuit 3 is provided with 512 bytes of user data DT0 to DT input from the outside of the optical disk device 1.
A 4-byte vendor unique area VU is added to 511. In the present embodiment, it is premised that the vendor does not have information to be recorded together with the user data, and a fixed value is prepared as data in the vendor unique area. In this embodiment, this constant value is 00H.

These data, together with the 4-byte error detection codes CRC0, CRC1, CRC2 and CRC3,
As shown in FIG. 3, it is divided into five correction sequences (code sequences 0 to 4) and interleaved. The error correction circuit 3 further adds error correction codes EC0, 0 to EC4, 15 of 16 bytes to each of these five code sequences and outputs each column to the data transfer circuit 4 in order from the first column of the code sequence 0. To do.

In the data transfer circuit 4, the error correction circuit 3
Out of the data input from, data other than the 4-byte constant value data in the vendor unique area is output to the recording / reproducing circuit 5 in the order of input.

The recording / reproducing circuit 5 records the data other than the vendor unique area transferred from the data transfer circuit to the designated sector on the surface of the disk medium 2 via the head 6.

Next, the case where the user data is reproduced from the sector of the disk medium 2 in the optical disk device 1 will be described. The recording / reproducing circuit 5 reads data from a designated sector on the surface of the disk 2 via the head 6,
Transfer to the data transfer circuit 4.

In the data transfer circuit 4, 4-byte data having a value of 00H is inserted after DT511 of the reproduction data input from the recording / reproduction circuit 5, and output to the error correction circuit 3 in the order input at the time of recording. By the operation in the data transfer circuit 4, the data in the vendor unique area deleted at the time of recording is restored.

In the error correction circuit 3, the data transfer circuit 4
The reproduced data thus transferred is again deinterleaved in the order shown in FIG. 3, and error correction is performed for each of the five code sequences. After that, the error detection code is used to check whether or not the corrected user data has been correctly corrected. If the corrected user data has been correctly corrected, the reproduction data is output to the outside of the optical disc device 1.

In the above embodiment, only the case where the vendor does not have the information to be recorded together with the user data has been described. However, when the vendor has the information to be recorded together with the user data, the error correction circuit in the data transfer circuit 4 is used. The data input from 3 may be directly transferred to the recording / reproducing circuit 5 without any operation. At this time, it is conceivable to provide the data transfer circuit 4 with a control means for detecting whether or not the data in the vendor unique area has a constant value, and thereby determining whether to perform the delete / insert operation on the constant value data.

[0029]

As described above, according to the present invention,
If there is no information that the vendor wants to record along with the user data, it is not necessary to record an unnecessary vendor unique area on the disk medium surface due to the error correction method, so the number of bytes in one sector can be reduced, and the user data can be recorded. There is an effect that the storage capacity of the disk medium that can be used for is increased as compared with the conventional one and becomes efficient.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an optical disk device according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a conventional optical disc device.

FIG. 3 is an explanatory diagram of an interleave error correction method.

[Explanation of symbols]

 1,200: Optical disk device 2,201: Disk medium 3,202: Error correction circuit 4: Data transfer circuit 5,203: Recording / reproducing circuit 6,204: Head

Claims (1)

[Claims] 1. An information recording / reproducing apparatus for recording / reproducing user data in sector units formed by dividing a track on a surface of a disk medium into a plurality of sectors, wherein the user data and constant value data are recorded when the user data is recorded. Is divided into a plurality of groups and is output after generating an error correction code in each group, and at the time of reproducing the user data, the data reproduced from the sector is error-corrected by the error correction code in the group unit. An error correction circuit that performs a correction, and when recording the user data, records the data output from the error correction circuit in the sector through a head, and when reproducing the user data, records the data through the head. A read / write circuit that outputs the read data read from the sector to the error correction circuit; It is provided between the recording / reproducing circuit,
When the user data is recorded, the constant value data is deleted from the data output from the error correction circuit, and when the user data is reproduced, the constant value data is added to the reproduction data output from the recording and reproduction circuit. An information recording / reproducing apparatus comprising: a data transfer circuit to be inserted.