JP2970073B2 - Data recording / playback 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 data recording / reproducing method suitable for recording / reproducing an optical disk which can be used in both the ISO format and the CD format.

[0002]

2. Description of the Related Art At present, there are optical disks having a format based on a CD (compact disk), such as a CD-ROM, in addition to a format standardized by the ISO (International Organization for Standardization). . These two formats have different sector configurations. That is, standardization is advanced by ISO, and in the format, the capacity of one sector is set to 512 bytes. On the other hand, in the CD format, a block in which one sector consists of 98 frames (245 blocks if a subcode is included)
0 bytes). For this reason, it is difficult to share data between ISO format data and CD format data.

[0003] Therefore, the development of an optical disk that can be shared by the ISO format and the CD format is being promoted. In such an optical disk, the capacity of one sector is 51
When recording data in ISO format, the 512-byte sector is used. When recording data in CD format, one sector is used for five sectors.
It may be a sector. If five 512-byte sectors are collected, 512 × 5 = 2560 (bytes), and one sector of data in the CD format (245
0 bytes).

[0004] That is, in a disk that can be shared with the CD format and the ISO format, two types of sector sizes can be set. One is a sector when recording / reproducing data in ISO format.
This is a 2-byte sector. The other is a sector for recording / reproducing data in the CD format, which is a 2560-byte sector formed by collecting five 512-byte ISO format sectors.

[0005]

However, in such a disk, if the number of 512-byte sectors provided in one track is not a multiple of 5, five 512-byte sectors are collected and formed. It becomes impossible to arrange an integral number of sectors for the CD format on one track. If the number of sectors in one track in the CD format is not an integer, it becomes difficult to access the sector in the CD format. If the number of 512-byte sectors arranged in one track is always set to a multiple of 5, the number of sectors in one track in the CD format becomes an integral number. However, this improves the data recording density. I can not plan.

Accordingly, an object of the present invention is to provide, for example,
It is an object of the present invention to provide a data recording method which can be easily accessed even when the number of sectors in one track is not an integer when five 12-byte sectors are collected to form a sector in the CD format.

[0007]

The present invention provides a sector S _ISO for a first format (ISO format).
In the use are data <br/> recording / reproducing method a disk sector and S _CD is possible to set for the second format (CD format), the first format (ISO
Format), the number of sectors per physical track is L
(For example, 32), the number of sectors per physical track of the second format (CD format) formed by collecting a plurality of sectors of the first format is M (for example, 6.4), and (M × N) Let N (for example, 5) be the minimum positive integer for which N is an integer, N physical tracks (for example, 5)
Track) as one logical track, recording / reproducing is performed in units of the logical track, and a memory having a data capacity of a positive integer multiple of the logical track is provided, and data in units of the logical track is time-axis compressed using the memory. / Data expansion / decompression method.

[0008]

[Operation] For example, the sector S _CD for the CD format
Is 6.4 sectors per physical track,
By making five physical tracks one logical track and recording / reproducing data for every five physical tracks, access becomes easy.

[0009]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of an optical disk that can be shared by the ISO format and the CD format. In the disk 1 shown in FIG. 1, a sector S _CD in CD format is 6.4 sectors distributed set to each track.
The sector S _CD is composed of, for example, five 512-byte ISO format sectors S _ISO . When data is recorded / reproduced on / from the optical disk 1, the rotation of the optical disk 1 is controlled at a speed higher than a normal rotation speed (a speed for achieving a desired transfer rate). Therefore, the time axis of the data is compressed / expanded using the memory.

As can be seen from FIG. 1, when the number of sectors S _CD in each track is not an integer, each track t ₁ ,
The head A _{1 of} the first sector S _CD 1 of t ₂ , t ₃ ,...
A ₂ , A ₃ ,... Are different for each track. Therefore, it is difficult to access a desired sector. Also,
It is difficult to manage the memory when compressing / expanding the time axis.
However, even if the number of sectors S _{CD in} each track is not an integer, the heads A ₁ and A ₆ of the head sector S _CD 1 are radially aligned every five tracks.

The present invention focuses on this.
That is, as shown in FIG. 2, a memory 2 capable of recording data for five physical tracks is prepared. Then, the optical disk 1 is rotated at a higher speed than the normal transfer rate, and the memory 2 compresses / expands the time axis of the recording data. At this time, data is recorded / recorded in units of five physical tracks.
Will be played.

That is, five physical tracks t _{1 to} t ₅
Are regarded as one logical track T, and a logical track number (T0, T1,...) Is assigned to every five physical tracks.
Then, one logical track has exactly 32 sectors (6.4 × 5 = 32). Sector numbers (Se0 to Se31) are assigned to 32 sectors in one logical track (physically 5 tracks). Sector S
_{The CD} has a logical track number (T
0, T1,...) And the sector numbers (Se0 to Se31) of 32 sectors in this one logical track. In this way, each logical track T0, T
At 1,..., Radial positions A ₁ , A at the beginning of the track
_6, ... it is the same, it is possible to easily access the desired sector S _CD.

In this case, in the case of sequential data, it is not necessary to monitor the memory. For example, as shown in FIG. 2, at the time of reproduction, the optical disc 1 is rotated at a speed four times the normal rotation speed. Then, a memory 2 having a size of 5 physical tracks is prepared. The optical disk 1 is reproduced for five physical tracks (one logical track), and data during the reproduction is stored in the memory 2. If memory 2 has the size of 5 physical tracks,
When the optical disk 1 is reproduced for five physical tracks, the capacity of the memory 2 is just filled. Next, the same five physical tracks are traced, and the data stored in the memory 2 is read at the original transfer speed, that is, four times as long. If you read the data in the memory four times as long,
In the meantime, the same five physical tracks are traced four times. Therefore, the same five physical tracks are traced five times, during which data is stored in the memory 2,
The data is read out four times as long. When the same physical track is traced five times, the reading / writing of the memory 2 is finished and the head of the next five physical tracks (the next logical track) is reached.

As described above, when the optical disk 1 is rotated at four times the normal rotation speed, the same five physical tracks (one logical track) are traced five times,
The data of the first five physical tracks may be written to the memory 2 and then the data of the memory 2 may be read at a quadruple length, so that monitoring of the remaining amount of data in the memory 2 becomes unnecessary.

FIG. 3 shows such a CD format and I
Recording / recording of optical disc 1 that can be shared with SO format
1 shows an example of a disk recording / reproducing apparatus for performing reproduction. This optical disk recording / reproducing apparatus is provided with a SCSI interface 21. By connecting the optical disk recording / reproducing device to the computer via the SCSI interface 21, this optical disk recording / reproducing device can be used.
The playback device can be operated as a peripheral storage device of a computer. The SCSI interface 21 is used to input / output data using the SCSI interface 21.
An I controller 22 is provided.

On this optical disc 1, data in ISO format and data in CD format are recorded / reproduced. A CD and CD-ROM encoder / decoder 24 are provided so that data can be recorded / reproduced on the optical disc 1 in a CD format. Further, an A / D converter 25 for converting an audio signal decoded by the CD-ROM decoder 24 into an analog signal is provided. The reproduced audio signal is taken out as a digital signal from the digital output terminal 26 and the analog output terminal 2
7 is output as an analog signal.

The rotation of the optical disk 1 is controlled by a spindle motor 11. The optical disc 1 is rotated at a speed higher than the speed at which a normal data transfer rate is achieved in order to improve data reliability and the like. For this reason, the data transfer rate for recording / reproducing data on the optical disc 1 is different from the data transfer rate for input / output. A RAM 18 is provided to match the data transfer rate for recording / reproducing data on the optical disc 1 with the data transfer rate for input / output. This RAM1
8 is controlled by the RAM controller 23. The control of the entire recording / reproducing apparatus is performed by the controller 28.

A magnetic head 12 faces the optical disk 1.
And the optical head 13 are provided so as to face each other.
The magnetic head 12 is driven by a magnetic head drive circuit 14. A reproduction signal of the servo area of the optical disk is supplied to the servo circuit 17 via the reproduction amplifier 19. The rotation of the spindle motor 11 is controlled by a servo circuit 17. In addition, tracking control is performed by the servo circuit 17.

At the time of data recording, data from the SCSI interface 21 or from the CD and CD-ROM encoder / decoder 24 is stored in the RAM 18,
The output of the RAM 18 is supplied to the modulation / demodulation circuit 15.
In the modulation / demodulation circuit 15, data is modulated by a predetermined modulation method. The output of the modulation / demodulation circuit 15 is supplied to the magnetic head drive circuit 14. A modulation magnetic field is generated from the magnetic head 12 by the output of the modulation / demodulation circuit 15. This modulation magnetic field is applied to the optical disc 1. At the same time, a laser beam is emitted from the optical head 13 according to the output of the laser drive circuit 16. This laser beam is applied to the optical disc 1. Thus, data is recorded on the optical disc 1 in the form of the magnetization direction of the perpendicular magnetization film.

At the time of reproduction, a laser beam from the optical head 13 is irradiated on the optical disk 1, and reflected light of the laser beam is detected. The rotation angle of the reflected light of the laser beam differs depending on the magnetization direction of the perpendicular magnetization film of the optical disc 1. The recorded data on the optical disc 1 is reproduced according to the rotation angle of the reflected light of the laser beam. The reproduction signal of the optical disk 1 is supplied to the modulation / demodulation circuit 15 via the reproduction amplifier 19. The modulation / demodulation circuit 15 demodulates the data. The output of the modulation / demodulation circuit 15 is stored in the RAM 18
Supplied to The output of the RAM 18 is decoded via the SCSI interface 21 or by the CD and CD-ROM encoder / decoder 24 and output.

[0021]

Effects of the Invention According to the present invention, for example, sector S _CD for CD format 1 physical tracks per 6.
In the case of four sectors, access is facilitated by setting five physical tracks as one logical track and recording / reproducing data for every five physical tracks (one logical track).
Also, when the disk is rotated at high speed,
By providing the memory for the five physical tracks (one logical track) and performing compression / expansion on the time axis, it becomes unnecessary to manage the memory.

[Brief description of the drawings]

FIG. 1 is a plan view used for describing an embodiment of the present invention.

FIG. 2 is a block diagram used for describing an embodiment of the present invention.

FIG. 3 is a block diagram of an example of a disk recording / reproducing apparatus to which the present invention can be applied.

[Explanation of symbols]

 1 optical disk

Claims (1)

(57) [Claims] 1. A sector and the data recording / reproducing method are use a disk sector and is settable for the second format for the first format, one physical track per first format The number of sectors is L, the number of sectors per physical track of the second format formed by collecting a plurality of sectors of the first format is M, and the minimum number where (M × N) is an integer is N. Then, the N physical tracks are defined as one logical track, recording / reproduction is performed in units of the logical tracks, and a memory having a data capacity of a positive integer multiple of the logical track is provided, and the data in units of the logical tracks is stored in the logical tracks. A data recording / reproducing method in which time axis compression / expansion is performed using a memory.