JP3489622B2 - Data recording method and data recording / reproducing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for recording and reproducing data on a disc-shaped recording medium or the like.

[0002]

2. Description of the Related Art In a data storage device such as a hard disk device, a floppy (registered trademark) disk device, or a magneto-optical disk device, the minimum unit of data access is a data block called a sector. Although these data storage devices are used as external storage devices of computers, conventionally, they are the access units 1
The data block size per sector (hereinafter referred to as sector size) was 512 bytes in the mainstream.

However, in recent years, due to the increase in the capacity of data files and the improvement in the reliability of data, an increase in the sector size has been called for, and in reality, it is 2K like a CD-ROM.
Media that handles data in units of bytes or approximately 2.5 Kbytes has also appeared. Therefore, 512 bytes,
There is a strong demand for compatibility between these large-capacity sector sizes, and various proposals have been made.

[0004]

[Problems to be Solved by the Invention]
Regarding the data from the recording medium recorded by the proposed data recording method, when compatibility is made between the small sector size A and the large sector size nA (n is an integer of 2 or more), some Switching is required, and a data encoding / decoding block according to the sector size is required, which complicates the configuration.

An object of the present invention is to provide a data recording method which does not cause the above-mentioned drawbacks when the data of the sector size A and the data of the sector size nA are made compatible with each other.

[0006]

In order to solve the above problems, a data recording method according to the present invention is a data recording method for recording recording data on a recording medium via a buffer memory, wherein the buffer memory comprises: Data size A
The data block (A is the data amount) is written in a data format including user data having a predetermined data amount and an error correction code for the user data, and has a data size of nA (n is an integer of 2 or more). The data block has a data format of n data blocks of the data size A, and when the data format of the data block of the data size nA is divided into n, the data of the data size A is divided. It is characterized in that the data is written in a block data format.

According to the present invention having the above-mentioned structure, the data format of the data block having the data size nA is completely described by the data format of the data block having the data size A. Therefore, when recording / reproducing data to / from the data recording medium according to the present invention, the size A
It is possible to encode and decode not only this data block but also the data block of size nA.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a data recording medium according to the present invention will be described below with reference to the drawings. The data recording medium of the embodiments described below is a disk medium. First, the overall configuration of an example of a disc recording / reproducing system for recording / reproducing a data recording medium according to the present invention will be described with reference to FIG.

In FIG. 2, reference numeral 1 denotes an optical disk, which is a rewritable optical disk in this example, for example, a magneto-optical disk. This optical disc 1 is rotationally driven by a spindle motor 2. The spindle motor 2 receives the servo signal from the servo circuit 5 and rotationally drives the optical disc 1 at a constant angular velocity (CAV), for example.

An optical head 3 is provided on one side of the optical disc 1.
Is provided. In addition, the optical head 3 of the optical disc 1
A magnetic head 6 is provided at a position facing the surface opposite to the surface facing the magnetic head. The optical head 3 and the magnetic head 6 are configured to move synchronously along the radial direction of the optical disc 1.

The optical head 3 comprises a laser light source and an optical detector, the laser light source is driven by a drive signal from the laser drive circuit 4, and the optical detector receives the reflected light from the disk 1 and obtains reproduction information therefrom. The laser drive circuit 4 also controls the output power of the laser light source of the optical head 3, and causes the laser light source to generate a laser beam having a power higher than that at the time of reproduction at the time of recording. Further, a servo control signal from the servo circuit 5 is supplied to the optical head 3, and thereby focus control and tracking control are performed.

An RF (Radio Frequency) signal reproduced from the optical disk 1 by the optical head 3 is supplied to the servo circuit 5 via a head amplifier 11. The servo circuit 5 forms a focus error, a tracking error, etc. from this RF signal, and forms a servo control signal to be supplied to the optical head 3 and the spindle motor 2 from this.

The reproduced signal from the head amplifier 11 is supplied to the modulation / demodulation circuit 12. The modulation / demodulation circuit 12 modulates recorded data and demodulates reproduced data. A signal detection circuit such as an NRZ binary value detection circuit or a partial response ternary value detection circuit is included in the preceding stage of demodulation.

Reference numeral 13 is a RAM for temporarily storing data for processing recorded data and reproduced data. Reference numeral 14 is a RAM controller that controls writing of recording data to the RAM 13 and reading of reproduction data. In this example, the SCSI interface is used for exchanging the recorded data and the reproduced data with another part, for example, a personal computer. 15
Is a SCSI controller for the SCSI interface, and in the case of this example, is configured to be capable of performing error correction encoding and decoding processing, data interpolation processing and the like.

Recording is performed as follows. That is,
The recorded data from the SCSI interface is SCS
It is temporarily stored in the RAM 13 via the I controller 15 and the RAM controller 14. Then, the data is appropriately read according to an instruction from the system controller 10, supplied to the modulation / demodulation circuit 12, modulated, and supplied to the magnetic head drive circuit 16. Magnetic head drive circuit 16
Performs driving by driving the magnetic head 6 so as to apply a modulation magnetic field according to the recording data to the optical disc 1.

In reproduction, the reproduced RF signal obtained from the photodetector of the optical head 3 is supplied to the modulation / demodulation circuit 12 through the head amplifier 11 and demodulated, and the demodulated data is stored in the RAM 13. Then, after processing such as error correction and interpolation is performed, the data is transferred to a reproduction data processing unit such as a personal computer via a SCSI interface.

[First Embodiment] In this embodiment, the user sector size is compatible with a small sector of 512 bytes / 1 sector and a medium sector of 1 Kbyte / 1 sector, or 512 bytes. The small sector of / 1 sector and the large sector of 2560 bytes / 1 sector are recorded on the disc 1 and reproduced.

In the case of this example, a small sector, a medium sector,
The data format of a large sector is shown in FIG.

FIG. 1A shows the data format of a small sector in this example. That is, 512 bytes (see FIG.
, B is an abbreviation for byte), and
As shown in FIG. 1A , a total of 520 bytes of 4-byte control data (shown with diagonal lines in the figure) and 4-byte CRC code are horizontal × vertical = 104 (bytes) × 5 (rows). Are arranged in a matrix. And
An error correction code is generated for this 520-byte data, and 80-byte (16 bytes × 5 rows) parity is added.

In the case of this example, as the error correction code, for example, (120, 104, 1) is applied to the data of 104 bytes in each row of the matrix array data.
7) A Reed-Solomon code is generated and 16-byte parity is generated. Therefore, the parity for 5 rows is 80 bytes, and the data for one small sector is 600 bytes in total.

The read / write (R / W) direction of data in this data format is the vertical direction. That is, at the time of recording, the data of the small sector transferred through the SCSI interface is R in the state of FIG. 1A.
Written to AM13. And when recording, R
Data is sequentially read from the AM 13 in the vertical (column) direction, for example, one byte at a time, and recorded on the disk 1. In this case, since there are 5 rows in the column direction and the error correction code is generated in the row direction, data is recorded by interleaving with an interleave length of 5 (bytes).

At the time of reproducing this small sector, data in byte units from the disk 1 is sequentially written in the RAM 13 in the vertical direction in FIG. 1A, and the data of the data format shown in FIG. 1A is reproduced. The error in this one small sector is corrected by using the parity if it is within the error correction capability of the error correction code.
Then, the data is transferred from the RAM 13 to the computer via the SCSI interface.

Next, FIG. 1B shows a data format of a medium sector having a sector size of 1 Kbyte in the case of this example. The data format of the medium sector has a structure equivalent to two data of the data format of the small sector stacked in the column direction. That is, the horizontal (row) direction has the same size as the small sector, and each row has 104
For byte data, for example, (120, 104,
17) A Reed-Solomon code is generated and 16-byte parity is added. And the vertical direction is 5 rows x 2 = 1
It is assumed to be line 0.

At the time of recording, the data of this middle sector is
RA via the SCSI interface in the state of FIG. 1B
Written to M13. When recording data on the disk, the data is sequentially read from the RAM 13 byte by byte in the vertical (column) direction and recorded on the disk 1. In this case, since there are 10 rows in the column direction and the error correction code is generated in the row direction, data is recorded by interleaving with an interleave length of 10 (bytes).

At the time of reproducing the medium sector, byte-unit data from the disk 1 is sequentially written in the RAM 13 in the vertical direction in FIG. 1B to reproduce the data in the data format shown in FIG. 1B. Then, the error in the middle sector is corrected by using the parity within the range of its error correction capability, and transferred from the RAM 13 to the computer via the SCSI interface.

At the time of recording / reproduction of the medium sector, the data format of the medium sector is exactly the same as the data format of the small sector in units of 5 columns, so the encoding / decoding circuit block of the small sector is used. The middle sector is encoded and decoded. Note that an interleave length switching circuit is necessary for the case of recording in a small sector.

Next, FIG. 1C shows the data format of a large sector with a sector size of 2.5 Kbytes in this example. The data format of this large sector has a structure equivalent to that in which five pieces of data of the data format of the small sector are stacked in the column direction. That is, the horizontal (row) direction has the same size as the small sector, and each row has 104
For byte data, for example, (120, 104,
17) A Reed-Solomon code is generated and 16-byte parity is added. And the vertical direction is 5 rows × 5 = 2
There are 5 lines.

At the time of recording, the data of this large sector is
RA via the SCSI interface in the state of FIG. 1C
Written to M13. And in recording, RA
Data is sequentially read from M13 in the vertical (row) direction byte by byte and recorded on the disk 1. In this case, since there are 25 rows in the column direction and the error correction code is generated in the row direction, interleaving with an interleave length of 25 (bytes) is performed and data is recorded.

At the time of reproducing this large sector, byte-unit data from the disk 1 is sequentially written in the RAM 13 in the vertical direction in FIG. 1C, and the data in the data format shown in FIG. 1C is reproduced. Then, the error in this one large sector is corrected within the range of its error correction capability using the parity, and transferred from the RAM 13 to the computer via the SCSI interface.

Also in the case of recording / reproducing of this large sector, since the data format of the large sector is exactly the same as the data format of the small sector in units of 5 columns, the encoding / decoding circuit block of the small sector is used. hand,
Encoding and decoding of this large sector are performed. Also in this case, an interleave length switching circuit is necessary for the case of recording in a small sector.

[Second Embodiment] In this example, the structure of the data format is exactly the same as that of the example of FIG.
The method of recording on the disc 1 is different.

In this example, recording / reproducing of the sample servo system is used. That is, in the sample servo type optical disc (including magneto-optical disc), as shown in FIG.
The servo area As in which the puddle mark including the pair of pits 21 and 22 is recorded is preformatted at a predetermined interval and is temporally and spatially separated from the data area Ad. This servo area As and data area A
A unit area including d is called a segment, and in the case of the sample servo system, data recording / reproduction can be performed in this segment unit.

In this example, the user sector size is, for example, 512 bytes / 1 small sector and 2 small sectors.
When recording / reproducing on / from the disc 1 while making it compatible with a large sector of 560 bytes / 1 sector, for example, as shown in the recording pattern on the disc 1 in FIG. Recording and reproduction are performed so that five data recording areas Db for one large sector are formed. Then, in this case, when writing data of one small sector to the disk 1, the data of one small sector is divided into units of one segment, and the divided data of one segment is divided into discrete segments. In the case of this example, one segment is recorded every five segments.

This example will be described in more detail.

FIG. 5 shows the track format in this example. In the case of this example, as shown in FIG. 5D, one segment includes a servo area of 4 bytes, a reference area of 1 byte for reproducing clock synchronization, and a user data area of 20 bytes.

As shown in FIG. 5A, one track consists of 30 small sectors (small sector numbers "0" to "29").
Sequentially include data for 30 small sectors). The data recording area Db of the large sector is formed by dividing one track into six. Therefore, the large sector recording area Db is composed of five data recording areas Ds for one small sector, as shown in FIG. 5B.

The data recorded in the data recording area Ds for one small sector is not the data itself in the small sector unit of the data format shown in FIG.
As shown in (5), the data in units of segments of five small sectors included in the large sector recording area Db are mixed.

That is, for example, small sector numbers "0" to
Looking at the data of 5 small sectors of “4”, FIG.
As shown in FIG. 5B and FIG. 5C, the data in the unit of segment of the small sector of number “0” is indicated by hatching in the figure, and the recording area Db is the size of five recording areas Ds.
Is recorded in every 1 segment of every 5 segments. In addition, the segment unit data of the small sector number “1” is stored in the segment next to the segment unit data of the small sector number “0”.
It is recorded in every 5 segments. Similarly, the data in segment units of the small sectors with the numbers “2”, “3”, and “4” are sequentially recorded in the adjacent segment every 5 segments.

In the case of this example, the data in small sector units is
In the data format of FIG. 1A, the data read / write (R / W) direction is the vertical (column) direction,
R for every 1 segment (4 bytes x 5 rows = 20 bytes)
It is read from the AM 13 and is recorded on the disc 1 in every 1 segment of every 5 segments, as shown in FIG. 5C.

In addition, the reproduced data is read from the disk 1 for one segment of every five segments and written in the RAM 13 in the vertical direction of FIG. 1A to complete the data format of FIG. 1A. Data is fetched from the disk 1 to the RAM 13 in units of the large sector recording area Db and written in the RAM 13 as in the data format of FIG. 1C, and only the necessary sector data is read out from the RAM 13.
It can also be taken out from the AM 13.

In the data format of FIG. 1C, the data of the large sector is 4 bytes in every 5 rows, that is, 1 segment in total of 20 bytes, sequentially in the vertical direction in the RAM.
The data is read from the disc 13 and continuously recorded on the disc 1. The recording pattern at this time is as shown in FIG. 5C, which is compatible with the recording pattern in units of small sectors described above.

In this case, in FIG. 1A, the data read / write (R / W) direction is the vertical (column) direction, but it is read from the RAM 13 for each one segment (4 bytes × 5 rows = 20 bytes). Then, as shown in FIG. 5C,
It is recorded on the disc 1 in every 1 segment of every 5 segments.

During reproduction, segments are continuously reproduced from the disc in units of recording areas Db of large sectors. This reproduced segment data is stored in RAM
13 is sequentially written in the vertical direction, the data format shown in FIG. 1C is formed, and the original large sector is formed.

According to the discrete recording / reproducing method in segment units as described above, since the data is written every 5 segments, the burst error correction length is shorter than that in the case of continuous writing as in the conventional case. 5 times,
Data reliability can be ensured even for small sector data.

As described above, also in this example, recording and reproduction can be performed in units of small sectors and in units of large sectors, and access to data in units of small sectors and access to data in units of large sectors. It is possible and compatible. The encoding / decoding circuit block only corresponds to the data format of the small sector, and the large sector can be encoded and decoded.

It should be noted that a small sector and twice the data capacity 1
For compatibility with the middle sector of KB, data for a small sector may be recorded in one segment of every two segments.

When the data recording method of the second embodiment is generalized, when the sector size A is compatible with the sector size nA (n is an integer of 2 or more), the data recording is i (i Is an integer greater than or equal to 1) segment unit,
The recording is performed in the i segment for each (i × n) segment.

The above example is not limited to the sample servo type optical disk, but can be applied to any recording medium having a concept similar to that of a segment.

The present invention is not limited to the case of recording data on a disk-shaped recording medium, but is also applicable to the case of recording data on another recording medium such as a card-shaped recording medium in data block units equivalent to sectors. It is possible.

[0050]

As described above, according to the present invention, for example, between the sector size A and the sector size nA (n
, The data format of the sector size nA is configured to be the data format of the sector of the sector size A when the data format of the sector size nA is divided into n. Only the sector corresponding to the data format of the sector of the sector size A can encode and decode the sectors of both sector sizes. Therefore, according to the present invention, it is possible to realize the recording / reproducing apparatus with a simple configuration.

[Brief description of drawings]

FIG. 1 is a diagram showing a data format for explaining an embodiment of a data recording medium according to the present invention.

FIG. 2 is a block diagram of an example of a disk recording / reproducing apparatus for recording / reproducing an embodiment of a data recording medium according to the present invention.

FIG. 3 is a diagram for explaining a sample servo system.

FIG. 4 is a diagram showing an example of a recording pattern on a disc.

FIG. 5 is a diagram showing a track format in an embodiment of a data recording medium according to the present invention.

[Explanation of symbols]

1 ... Magneto-optical disk, 3 ... Optical head, 6 ... Magnetic head, 13 ... RAM, Db ... Large sector recording area, Ds
… Small sector data recording area, As… Servo area, Ad… Data area

Claims (2)

(57) [Claims] 1. A data recording method for recording recording data on a recording medium via a buffer memory, wherein a data block of a data size A (A is a data amount) is stored in the buffer memory.
A data block of a data size nA (n is an integer of 2 or more) is written in a data format consisting of a predetermined amount of user data and an error correction code for the user data. The data format of the data block has a data format of n, and the data format of the data block of the data size nA is written in a state in which the data format of the data block of the data size A is obtained by dividing the data format by n. Data recording method characterized by. 2. A data recording / reproducing method in which recorded data is recorded in a recording medium via a buffer memory, and data read from the recording medium is once written in the buffer memory for reproduction. In the buffer memory or the buffer memory at the time of reproduction, a data block having a data size A (A is a data amount) is
A data block of a data size nA (n is an integer of 2 or more) is written in a data format consisting of a predetermined amount of user data and an error correction code for the user data. The data format of the data block has a data format of n, and the data format of the data block of the data size nA is written in a state in which the data format of the data block of the data size A is obtained by dividing the data format by n. A data recording / reproducing method characterized by the above.