JP3120084B2 - Disk-shaped recording medium - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method in which sectors which are equally spaced in the circumferential direction are provided to form a two-dimensional array of data arranged obliquely. For a disk-shaped recording medium on which interleaving delay processing is performed and parity is added and recorded over a plurality of sectors, for example, a compact disk
It is used for a data recording / reproducing system of data format conforming to the (CD) standard, a packet communication system and the like. 2. Description of the Related Art Conventionally, a compact disk (C) has been used as a digital audio disk for music in which digital audio data is recorded on an optical disk as a recording medium.
D: Compact Disc) is widely and generally known. The music CD adopts a double encoding system using two Reed-Solomon codes, and digital data obtained by digitizing an original audio signal is divided into predetermined numbers and arranged in a two-dimensional array. , for example, as shown in FIG. 7, seeking parity (P) for each row of the data string to form a Reed-Solomon code (C _2), each line was added to the Reed-Solomon code (C ₂₎ The data is subjected to interleave delay processing to obtain a parity (Q) for a data string positioned in an oblique direction of the two-dimensional array data block, and form and add a Reed-Solomon code (C ₁ ). Cross Interleave Reed-Solomon Code (CIRC)
n Code) makes it possible to perform signal processing with high error correction capability and obtain a very high quality reproduced audio signal. [0003] Also, disc specifications, recording formats,
Both the modulation method and the error detection / correction method are the same as the music CD, and the code information is written in a portion (data area) of the music CD where the music information is stored.
-ROM (Read Only Memory) is standardized. In the music CD system, data is processed with one frame (588 channel bits) as one unit.
In the CD-ROM, 98 frames are defined as one unit, that is, one sector, and data processing is performed by inserting a sector address into a control signal (user's bit) portion at the beginning of each frame. Further, the above-mentioned music CDs and CD-ROMs
Is a read-only optical disk.
W (Direct Read After Write) type optical disks and recordable and reproducible magneto-optical disks have also been developed and are being put to practical use. [0005] By the way, a CD having a data format conforming to the standard of the music CD described above.
In the ROM, when the recorded contents are schematically shown in FIG. 8 as two-dimensional array data, a unit recording area for one sector shown by a broken line in FIG. SC _n ) to the data block (D) composed of one sector of data obtained by adding the two series of Reed-Solomon codes (C ₁ ) and (C ₂ ) as described above.
B _n ) is divided into three sectors (S
C _n ), (SC _{n + 1} ), and (SC _{n + 2} ), and are encoded so as to extend over the three sectors (SC _n ) and (SC _n ) during reproduction.
Unless reproduction for ( _{n + 1} ) and (SC _{n + 2} ) is performed, the data block (DB _n ), that is, data for one sector cannot be completely read. Therefore, using a write-once optical disk, a magneto-optical disk, or the like, a CD-W that is upwardly compatible with the music CD or CD-ROM.
ORM (Write Once Read Many) and CD-RAM (Random
In the case of implementing an Access Memory, when data is written or rewritten to one sector (SC _n ) shown by hatching in FIG. 8, the subsequent sectors (SC _{n + 1} ) and (SC _{n + 2} ) And the Reed-Solomon code (C ₁ ′) of, and extremely complicated processing is required to avoid the influence. In view of the above-mentioned conventional problems, the present invention divides data to be transmitted into a predetermined number, such as a data format conforming to the music CD standard, and arranges the data in a two-dimensional array. In the data transmission method of performing interleave delay processing on serialized data strings positioned in the diagonal direction of the two-dimensional array data with respect to the data blocks thus formed, adding parity for each data string, and sequentially transmitting, A series of data blocks composed of data to be transmitted, that is, data files can be easily modified without requiring processing, and upward compatibility with the music CD or CD-ROM is achieved. An object of the present invention is to realize a data processing system using a certain CD-WORM or CD-RAM as a recording medium. SUMMARY OF THE INVENTION The present invention has a plurality of sectors in which tracks are divided at equal intervals in a circumferential direction, and the plurality of sectors divide recording data into sector units. The two-dimensional array of data in which a data block composed of data of a predetermined pattern that does not change parity before and after a series of two-dimensionally arranged data blocks is provided with a parity of a data sequence in the row direction of the two-dimensional array data. Is added, the parity of the diagonal data sequence of the two-dimensional array data is added, and the data of the diagonal data sequence of the two-dimensional array data is recorded as serial data from the beginning of a series of sectors, Sectors are recorded before and after a series of sectors including the recording data, in which data of a predetermined pattern that does not change parity is recorded. You. An embodiment of the present invention will be described below with reference to the drawings. A case in which data is transmitted via a magneto-optical disk conforming to the CD standard to which the present invention is applied will be described below. In this embodiment, as schematically shown in FIG. 2, a spiral track 2 is formed on the magneto-optical disk 1, and a plurality of tracks 2 are formed at equal intervals in the circumferential direction. Unit recording area, that is, sector (SC ₁ ), (SC
₂ ) are provided. Each sector has 12 bytes for the synchronization signal, 4 bytes for the header, and 2 bytes for the user data.
By allocating 288 bytes to system data such as 048 bytes and error correction code, data having 98 frames (2352 bytes) in the CD format as one unit is recorded. In the recording system of the recording / reproducing system using the magneto-optical disk 1, as shown in the block diagram of FIG.
The header and user data are one frame in the CD format, that is, 24-byte parallel data (S ₁ ), (S
₂ )... (S ₂₄ ) are sequentially input to the first Reed-Solomon encoder 3, and the first Reed-Solomon encoder 3 outputs parity (P ₁ ), (P P ₂ ),
(P ₃ ) and (P ₄ ) are obtained to form a Reed-Solomon code (C ₂ ). Parity is added to the above parallel data (S ₁ ), (S ₂ ) ... (S ₂₄ )
(P ₁ ), (P ₂ ), (P ₃ ), 28-byte parallel data (S ₁ ) to which (P ₄ ) is added (S ₁ ), (S ₂ ) ... (S ₂₄ ), (P ₁ ), (P ₁ ) _{P 2), (P 3)} , (P 4)
Are sequentially input to a second Reed-Solomon encoder 5 via an interleave delay circuit 4. The second Reed-Solomon encoder 5 converts the 28-byte parallel data (S ₁ ′), (S ₂ ′)... (S ₂₄ ′) subjected to the interleave delay processing by the interleave delay circuit 4. ), (P ₁ '),
Parity of (P ₂ '), (P ₃ '), (P ₄ ') every 28 bytes
Reed-Solomon code for (Q ₁ ), (Q ₂ ), (Q ₃ ), (Q ₄ )
(C ₁ ) is formed. Then, the parallel data (S ₁ '), (S ₂ ')
_{··· (S 24 '), (} P 1'), (P 2 '), (P 3'), parity (Q ₁₎ to _{(P 4 '), (Q} 2), (Q 3), ( Q ₄ ) with 32-byte parallel data (S ₁ '), (S ₂ ') ・ ・ ・ (S ₂₄ '), (P ₁ '), (P ₂ '),
(P ₃ ′), (P ₄ ′), (Q ₁ ), (Q ₂ ), (Q ₃ ), and (Q ₄ ) are converted into serial data (Dn) by the multiplexer 6 and Is recorded on the magneto-optical disk 1 via the. The user data recorded on the magneto-optical disk 1 in the recording system employing such a cross-interleaved Reed-Solomon code (CIRC) includes each sector (S
When the recorded contents for C ₁ ), (SC ₂ )... (SC _n ) are schematically shown in FIG. 1 as two-dimensional array data, they are divided by broken lines in FIG. For each of the indicated sectors (SC ₁ ), (SC ₂ )... (SC _n ), for example, one sector obtained by adding the two-series Reed-Solomon codes (C ₁ ) and (C ₂ ) described above. The unit data block (DB _N ) composed of the data shown in FIG.
It is encoded and recorded so as to be distributed over the sectors (SC _n ), (SC _{n + 1} ), and (SC _{n + 2} ). Then, in the magneto-optical disk 1 according to the present invention, a series of data blocks (DB _N ) composed of user data, with one sector of data as one data block.
As shown in FIG. 4, at the beginning of the user data block (DB _N ), two data blocks (DBZ _n−1 ), (DBZ _n−1 ) composed of predetermined data “0” are recorded.
_n-2 ) is added and recorded. As shown in FIG.
Predetermined data "0" at the beginning of the user data block (DB _N )
Data block (D
BZ _n−1 ) and a data block (DBZ _{n + 1} ) for one data block composed of the predetermined data “0” at the end. As shown in FIG. 6, at the end of the user data block (DB _N ), two data blocks (DBZ
_{n + 1} ) and (DBZ _{n + 2} ). , A series of data blocks (DB _N ) composed of the above user data and a series of data blocks (DB _N-1 ) composed of other user data located before and after the series of data blocks (DB _N-1 ), ( DB _{N + 1} ), two data blocks (DBZ _n-2 ), (DBZ _n-1 ),
Recording is performed so that (DBZ _{n + 1} ) and (DBZ _{n + 2} ) are arranged. As described above, a series of user data blocks (DB _N ) composed of the above-mentioned user data is composed of user data blocks (DB _N−1 ) composed of other user data located before and after the series. , (DB _{N + 1} ), two data blocks (DBZ _n−2 ), (DBZ _n−1 ), and (DBZ _{n + 1} ) of two data blocks each composed of the predetermined data “0”. , (DBZ
_{n + 2} ), the user data block
(DB _N ) is the user data block before and after (DB _N-1 ),
(DB _{N + 1} ) does not affect each parity (Q), that is, Reed-Solomon code (C ₁ ). Therefore, by using the magneto-optical disk 1 as a CD-RAM, data can be rewritten and edited in arbitrary user data block (DB _N ) units. The present invention is not applied only to a CD-RAM using the magneto-optical disk 1 as in this embodiment, but is applied to a CD-WOR using a write-once optical disk.
The present invention can also be applied to a disk-shaped recording medium employing a data format other than M or the CD format. According to the disk-shaped recording medium of the present invention,
Since the sector recorded with the data of the predetermined pattern added is arranged before and after the series of data sectors, the parity of the data recorded in the series of data sectors is not affected by other data. Alternatively, it does not affect the parity of the data recorded in the next series of data sectors. Therefore, according to the present invention, data recorded in a series of data sectors can be easily corrected without requiring complicated data processing, and the music CD or CD-ROM can be easily modified. CD-WORM and CD-RAM with upward compatibility for
Can be realized as a data processing system in which is used as a recording medium.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing a recording state of a CD-RAM to which the present invention is applied as two-dimensional data. FIG. 2 is a schematic diagram showing a disk format of the CD-RAM. FIG. 3 is a block diagram showing a configuration of a recording system of the CD-RAM. FIG. 4 is a schematic diagram for explaining an example of data recording on a magneto-optical disk according to the present invention. FIG. 5 is a schematic diagram for explaining another example of data recording on the magneto-optical disk according to the present invention. FIG. 6 is a schematic diagram for explaining another example of data recording on the magneto-optical disk according to the present invention. FIG. 7 is a schematic diagram for explaining a cross-interleaved Reed-Solomon code adopted in a CD format. FIG. 8 is a schematic diagram showing a general recording state in a CD format as two-dimensional data. [DESCRIPTION OF SYMBOLS] 1 magneto-optical disk, 2 tracks, SC _N sectors,
DB _N user data block, DBZ _N additional data block

Claims (1)

(57) [Claims] It has a plurality of sectors in which the track is divided at equal intervals in the circumferential direction, and the plurality of sectors have parity before and after a series of data blocks in which recording data is divided into sector units and two-dimensionally arranged. The parity of the data sequence in the row direction of the two-dimensional array data is added to the two-dimensional array data in which the data block configured by the data of the predetermined pattern that is not changed is changed. Parity is added, and the data of the data series in the oblique direction of the two-dimensional array data is recorded from the beginning of a series of sectors as serial data, so that the parity is not changed before and after the series of sectors including the recording data. A disk-shaped recording medium provided with sectors in which pattern data is recorded. 2. 2. The disk-shaped recording medium according to claim 1, wherein said predetermined pattern comprises zero data.