JP2868744B2 - Data recording method, recording apparatus, reproducing apparatus and 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 data recording method for recording data on a recording medium such as an optical disk, a recording apparatus thereof, a reproducing apparatus and a reproducing method thereof .

[0002]

2. Description of the Related Art In an optical disk recording / reproducing system, a modulation method adapted to optical characteristics is used for the purpose of improving recording density and stabilizing signal reproduction, and a predetermined unit is used to prevent a data error from being propagated due to a scratch on a disk. Formatting is performed to group data.

FIG. 8 shows a sector format used for a general rewritable optical disk. As shown in the figure, a sector is composed of a header section and a data section in which actual recording data (user data) is recorded. In the header part, SM (sector mark) 1, VFO
2, AM (address mark) 3, address information (ID)
4 are recorded. The address information 4 includes a track number 9, a sector number 10, and a CRC (Cyclic Redundancy Co.).
de) 11). The CRC 11 is a code for detecting a data error of the track number 9 and the sector number 10.

[0004] Incidentally, there is a case where the data portion is divided into a plurality of frames as shown in FIG. 1 and a synchronization pattern (SYNC) is added to each frame. The playback device extracts the synchronization pattern, extracts the periodicity of the frame from the pattern, and uses it for various timing controls.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a data recording method and a recording apparatus, and a reproducing apparatus and a reproducing method capable of efficiently extracting not only a frame periodicity but also a sector periodicity. To provide.

[0006]

Data recording method according to claim 1 in order to achieve the above object Means for Solving the Problems] are each identical bit
Data recording data sectors of betting amount of a plurality of frames as a unit for recording data on a recording medium that will be recorded
The method , wherein the sector is arranged at a head of each frame, and a synchronization pattern indicating a period of the frame, and a synchronization pattern is arranged at a head frame of the sector so as to be adjacent to the synchronization pattern. And a signal pattern indicating Recording apparatus according to claim 2 is the respective recording apparatus for performing signal recording sector comprising a plurality of frames of the same number of bits as a unit to the recording medium, separating them in the synchronization pattern and the sector indicates the period of the frame Means for generating a signal pattern indicative of: and the synchronization pattern is arranged at the head of each frame, and the signal pattern is arranged adjacent to the synchronization pattern at the head frame of the sector, and Means for formatting into a data sequence. Reproducing apparatus according to claim 3 is the recording medium on which data is recorded <br/> sectors each comprising a plurality of frames of the same number of bits as a unit, the placed at the beginning of each frame, said frame In a reproducing apparatus for reproducing a recording medium comprising a synchronization pattern indicating a cycle of the sector and a signal pattern which is arranged adjacent to the synchronization pattern in a leading frame of the sector and indicates a division of the sector, Means for reading recorded data, means for extracting the synchronization pattern from the read data, means for extracting the signal pattern from the read data, and based on the extracted synchronization pattern, Means for extracting the periodicity of the frame. A reproducing apparatus according to a fourth aspect is the reproducing apparatus according to the third aspect, further comprising means for extracting the periodicity of the sector based on the extracted signal pattern. The playback device according to claim 5 is
5. The reproducing apparatus according to claim 4 , further comprising means for controlling a demodulation timing of the data based on a periodicity of the extracted frame and a periodicity of a sector.
The reproducing apparatus according to claim 6 is the reproducing apparatus according to claim 4 , further comprising means for controlling a timing of writing the data to the memory based on the periodicity of the extracted frame and the periodicity of the sector. Have. The reproduction method according to claim 7, wherein the plurality of frames each having the same number of bits are used.
Recording medium on which data is recorded in units of sectors
And is located at the beginning of each frame, and
A synchronization pattern indicating the frame cycle and the start of the sector
A frame disposed adjacent to the synchronization pattern;
Recording medium having a signal pattern indicating a sector break
In a reproducing method for reproducing a body, the recorded information is recorded on the recording medium.
Reading the read data; and
Extracting the synchronization pattern from the data,
A step of extracting the signal pattern from the read data;
Based on the step and the extracted synchronization pattern,
Extracting the periodicity of the frame .

[0007]

[0008]

[0009]

[0010]

[0011]

[0012]

[0013]

[0014]

According to the present invention, since the synchronization pattern and the signal pattern indicating the division of the sector are arranged adjacent to each other, not only the periodicity of the frame but also the periodicity of the sector can be efficiently extracted.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a sector format in an optical disk according to one embodiment of the present invention.

In the optical disk of this embodiment, 4-9 modulation which is one of RLL (Run Length Limited) modulation is adopted for data encoding. The 4-9 modulation is a method of converting 4-bit data into a 9-bit signal pattern. The details of the 4-9 modulation are described in, for example, Japanese Patent Application No. 5-76692.
As shown in FIG. 1, one sector is composed of 42 frames. The first frame therein is the header section 21 and 33
Consists of bytes. The 41 frames other than the first frame are the data section 22, and are composed of a total of 1353 bytes. One optical disk is composed of several consecutive sectors.

The header section 21 includes a DCC (23) + SYNC (24) of a total of 2 bytes as a first synchronization pattern, a 4-byte AM (address mark) (25) as a second synchronization pattern, a sector number, and the like. , A 4-byte ID (26) which is address information including a first CRC (2
7), 0.5 byte DCC (28), 8 byte SL
D-1 (29), a 2-byte second CRC (30),
0.5 byte DCC (31), 8 byte SLD-2
(32) and a 2-byte third CRC (33).

Here, DCC (23, 28, 31) is
This is a cancel code added to suppress the direct current (DC) component of the signal after the NRZI conversion. SYNC (2
4) is a synchronization code for generating timing for extracting data in byte units at the time of 4-9 demodulation. The frame synchronization signal composed of the DCC (23) and the SYNC (24) is independent of the modulation rule of the 4-9 modulation, ie, 4
It is made to include a signal pattern that does not exist in the -9 modulation code. AM (25) which is the second synchronization pattern
Is data indicating the position of the succeeding ID (26) and at the same time indicating the division of the sector. This AM (25) is also 4-
It is made of a signal pattern that does not exist in the 9 modulation codes.
The ID (26) is data indicating a sector number as address data. The first CRC (27) is an error check code for ID (26). SLD (Center
Link data) -1 (29) and SLD-2 (32)
Is data indicating the data type (for example, video signal, character data, etc.) in the sector, the subordination of the sector, and the like. Second
CRC (30) is an error check code for SLD-1 (29). The third CRC (33) is SLD
-2 (32) is an error check code.

On the other hand, each of the second to forty-second frames (data part 22) in the sector has a 2-byte frame synchronization signal (DCC (41) + SYNC (42)),
Byte user data (43), 0.5 byte DCC
(44) 10-byte user data (45), 0.5
It consists of a byte DCC (46) and 10 bytes of user data (47). Here, the frame synchronization signal (DCC (41) + SYNC (42)) includes a signal pattern that does not exist in the 4-9 modulation code, similarly to the frame synchronization signal of the first frame (header section 21) described above. Have been. User data (43, 45, 47)
Includes an ECC (error correction code).

FIG. 2 is a diagram showing the structure of a code conversion table for 4-9 modulation. In the figure, Dn delimits an input binary data string in units of 4 bits, and uses h in hexadecimal notation.
ex displayed. Tn is a binary bit pattern obtained by converting the input Dn into 9 bits. At Tn, at least bit “0” is placed between bit “1” and bit “1”.
Are selected only when three or more exist. here,
Depending on Dn, two or three types of Tn patterns are prepared in consideration of the following data (Dn + 1), and the Tn pattern is determined according to the value of Dn + 1. For example, Dn = 5
In this case, there are two types of Tn, "000000100" and "000010001", and when Dn + 1 is (6, 7, 8, D, F), "00"
0010001 "is selected, otherwise" 000000100 "
When "000010001" is selected as Tn, depending on Dn + 1 and Dn + 1, subsequent Dn + 2 also follows the table shown in Case (1) of FIG. , D is 5 → 6 → 7, “00001000
1 "" 000000000 "" 100001000 "is obtained as the conversion result.

The shortest code inversion length (Tmin) of the 4-9 modulation code is 4T, and the longest code inversion length (Tmax).
Is 18T.

Next, the frame synchronization signal (DCC + SYNC) in each frame and the AM (2
The details of the signal pattern 5) will be described.

FIG. 3 shows a frame synchronization signal (DCC + SYN).
C) and the NRZI
FIG. 4 is a diagram illustrating a converted signal pattern. here,"*"
Is “1” or “0”, and DCC is determined by this value. That is, the DCC 4-9 modulation code is “000001”.
000 "and" 010001000 ", and of these two types of DCC, the pattern with the smaller DSV (Digital Sum Value) is selected.

When this frame synchronizing signal is subjected to NRZI conversion, as shown in FIG. 3, a signal pattern is obtained in which the maximum code inversion length (Tmax) of the 4-9 modulation code is 18T followed by the code inversion length of 7T. . A pattern in which the code inversion length of 18T is followed by the code inversion length of 7T does not exist in the 4-9 modulation code. Therefore, the frame synchronization signal can be uniquely distinguished from other signal patterns, and its detection can be performed easily and accurately.

FIG. 4 is a diagram showing AM (25) binary data and a signal pattern obtained by subjecting the binary data to NRZI conversion. When the pattern before the NRZI conversion of AM (25) shown in the figure is subjected to NRZI conversion, as shown in FIG.
A signal pattern is obtained in which the code inversion length of 8T continues after the code inversion length of 4T continues 14 times, and the code inversion length of 8T or more continues. Here, 4T is the shortest code inversion length (Tmin) of the 4-9 modulation code. And a signal pattern in which the code inversion length of 4T is continuous 14 times does not exist in the 4-9 modulation code. As described above, the signal pattern expressing AM (25) includes a signal pattern which is not present in the 4-9 modulation code and in which the code inversion length of 4T is continuous 14 times, so that AM (25) can be added to other signals. , And can be easily and accurately detected.

FIG. 5 is a diagram showing a data arrangement in a state where an ECC (error correction code) is added to user data. In this example, six sectors are combined into one ECC group, and a product code having two series of error correction codes C1 and C2 is used. Note that the error correction code C1 is (90,
84,7), the error correction code C2 is ^{P (x) = x 8 +} x 4 + x 3 + Reed-Solomon code the x ² +1 and a primitive polynomial such as (84,78,7). In these two series of error correction codes, the generation and error correction processing of the C1 error correction code are performed using 90 bytes for one row in the horizontal arrow X direction in the figure as one series. The generation and error correction processing of the C2 error correction code are performed using 84 bytes in the diagonal arrow Z direction in the figure as one series. Here, SYNC and DCC in the sector format shown in FIG. 1 are not included in the generation of the error correction codes C1 and C2 of each stream and the error correction processing. That is, in the header section 21, AM (25), ID (26), first CRC (2
7), SLD-1 (29), second CRC (30), S
LD-2 (32) and the third CRC (33) are the targets. However, since the AM (25) uses a special signal pattern that does not depend on the modulation rule as described above, the AM (25) cannot be included in the calculation range of the error correction codes C1 and C2 as it is. Therefore, for AM (25), error correction codes C1, C2 on the recording device side are used.
Before performing the calculation operation, the error correction codes C1 and C2 are generated after replacing the data with some fixed data in accordance with the modulation rule.

On the other hand, in the data section 22, all of the user data except for the DCC and the SYNC are subjected to the generation of the error correction codes C1 and C2 and the error correction processing.

Next, a recording apparatus for recording a signal on the optical disk of this embodiment will be described. FIG. 6 is a block diagram showing the configuration of this recording apparatus.

As shown in FIG.
1, fixed data generation circuit 62, first selection circuit 63, parity generation circuit 64, 4-9 modulation circuit 65, formatting circuit 66, AM generation circuit 67, second selection circuit 6
8 and an NRZI modulation circuit 69. This recording device operates as follows.

First, data to be recorded on the optical disk is stored in the memory 61. Here, the data stored in the memory 61 includes user data such as video and audio, ID, CRC,
SLD. Thereafter, data is read from the memory 61 in accordance with the respective sequence processes of C1 and C2 in the parity generation circuit 64 and sent to the parity generation circuit 64 through the first selection circuit 63. However, at this time, only the AM data area has 4-byte fixed data (for example, "00", "00", "00", "0") from the fixed data generation circuit 62.
0 ") is selected and sent to the parity generation circuit 64.

The parity generation circuit 64 calculates error correction codes C1 and C2 for each of the sequences C1 and C2, adds these to the recording data, and sends them to the 4-9 modulation circuit 65. The 4-9 modulation circuit 65 converts the input data sequence into a 4-9 modulation code, and outputs this to the formatting circuit 66. The formatting circuit 66 adds SYNC and DCC of a predetermined signal pattern to the 4-9 modulated data sequence, and formats the data sequence into a data sequence in sector units.

Thereafter, the sector data is sent to the NRZI modulation circuit 69 and subjected to NRZI modulation.
Only in the data area of M, the predetermined signal pattern shown in FIG.
Send to Thereafter, the NRZI-modulated sector data is:
The data is recorded on the optical disk by a recording processing unit (not shown).

As described above, in this embodiment, the AM (25)
Is replaced with fixed data and is included in the range of operation for generating an error correction code, whereby a sector can be configured with a multiple of the frame period. Moreover, the fixed data of this AM is NR
Since the original AM signal pattern is restored just before the ZI modulation, the AM function can be reliably performed.

Next, a reproducing apparatus for reproducing a signal from the optical disk on which recording has been performed as described above will be described. FIG. 7 is a block diagram showing a configuration of the reproducing apparatus.

As shown in the figure, the playback device is a SYNC
Detection circuit 71, frame synchronization circuit 72, AM detection circuit 7
3. Sector synchronization circuit 74, timing circuit 75, 4-9
Demodulation circuit 76, selection circuit 77, fixed data generation circuit 7
8, a memory 79, an error correction circuit 80, and a CRC check circuit 81. The operation of the playback device will be described below.

First, a signal is read from the optical disk by a reproduction processing unit (not shown), and the read signal is
The signals are sent to the C detection circuit 71 and the AM detection circuit 73, respectively. The SYNC detection circuit 71 detects a SYNC pattern from the input disk reproduction signal. Thereafter, the frame synchronization circuit 72 outputs the SYNC signal from the SYNC detection circuit 71.
The periodicity of the frame is extracted based on the detection signal. At this time, synchronization protection is performed so that synchronization is not easily disturbed even if some SYNC loss occurs.

On the other hand, the AM detection circuit 73 extracts an AM pattern that appears once for SYNC 42 times. The sector synchronization circuit 74 extracts the periodicity of the sector based on the AM detection signal from the AM detection circuit 73. At this time, similarly to the frame synchronization circuit 72, synchronization protection is performed so that sector synchronization is not disturbed even when an AM pattern is lost.

The timing circuit 75 receives the synchronization signals obtained by the frame synchronization circuit 72 and the sector synchronization circuit 74, and generates a demodulation timing signal of the 4-9 demodulation circuit 76 and a write address signal for the memory 79.

4-9 The demodulated data is sent to the memory 79. At this time, only the AM area is selected by the selection circuit 77 from the fixed data generation circuit 78 and sent to the memory 79. This fixed data is the same data as the fixed data generated by the fixed data generation circuit 62 of the printing apparatus (for example, “00”, “00”, “00”, “00”).
It is.

Thereafter, the data is read from the memory 79, and the error correction circuit 80 performs an error correction process. At this time, the data to be error-corrected are not only user data, but also the ID (26) of the header 21 and the CRC.
(27), SLD-1 (29), CRC (30), SL
D-2 (32) and CRC (33) are also included in the object, and even if an error occurs in these portions, it can be corrected to correct data within a correctable range.

In this reproducing apparatus, if necessary,
4-9 The demodulated data is taken into the CRC check circuit 81, and the ID of the header section 21 is output without waiting for error correction processing.
(26) Error detection of SLD-1 (29) and SLD-2 (32) can be performed. CRC check circuit 81
Is supplied to the control circuit, and predetermined control processing according to the situation is executed.

For example, when it is desired to accurately recognize and correct an error, such as during normal reproduction, it is sufficient to perform only error correction processing. When, as in a search operation, to recognize an error as soon as possible, By activating the CRC check circuit 81, error detection of the header section 21 can be performed, and can be used for subsequent control processing.

[0044]

As described above, according to the present invention, since the synchronization pattern and the signal pattern indicating the division of the sector are arranged adjacent to each other, not only the periodicity of the frame but also the periodicity of the sector is obtained. Can also be taken out efficiently.

[Brief description of the drawings]

FIG. 1 is a diagram showing a sector format in an optical disc according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a configuration of a code conversion table for 4-9 modulation.

FIG. 3 is a diagram showing binary data of a frame synchronization signal (DCC + SYNC) and a signal pattern obtained by subjecting the binary data to NRZI conversion.

FIG. 4 is a diagram showing AM (25) binary data and a signal pattern obtained by subjecting the binary data to NRZI conversion.

FIG. 5 is a diagram showing a data arrangement in a state where an ECC (error correction code) is added to user data.

FIG. 6 is a block diagram illustrating a configuration of a recording apparatus.

FIG. 7 is a block diagram illustrating a configuration of a playback device.

FIG. 8 is a diagram showing a sector format used for a rewritable optical disk.

[Explanation of symbols]

21 ... header part, 22 ... data part, 23, 28, 31,
41, 44, 46 ... DCC, 24, 42 ... SYNC, 2
5 AM, 26 ID, 43, 45, 47 user data and error correction code, 29 SLD-1, 32 SLD
-2, 61 ... memory, 62 ... fixed data generation circuit, 63
... First selection circuit, 64... Parity generation circuit, 65.
-9 modulation circuit, 66 ... formatting circuit, 67 ... AM
Generation circuit, 68 second selection circuit, 69 NRZI modulation circuit, 71 SYNC detection circuit, 72 frame synchronization circuit, 73 AM detection circuit, 74 sector synchronization circuit, 75
... Timing circuit, 76 ... 4-9 demodulation circuit, 77 ... Selection circuit, 78 ... Fixed data generation circuit, 79 ... Memory, 80
... error correction circuit, 81 ... CRC check circuit.

Continuation of front page (56) References JP-A-4-286768 (JP, A) JP-A-3-185684 (JP, A) JP-A-2-306470 (JP, A) JP-A-2-306471 (JP) JP-A-60-50667 (JP, A) JP-A-4-252469 (JP, A) JP-A-55-129913 (JP, A) JP-A-63-13170 (JP, A) JP-A-63-13170 61-25328 (JP, A) JP-A-61-142575 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G11B 20/12

Claims (7)

(57) [Claims] From 1. A plurality of frames of each the same number of bits
A recording medium on which data Ru is recorded becomes a sector as a unit
A data recording method for recording data , wherein the sector is arranged at a head of each frame, and a synchronization pattern indicating a cycle of the frame, and a synchronization pattern is arranged at a head frame of the sector adjacent to the synchronization pattern. the data recording method characterized by comprising a signal pattern indicating the ward out of the sector. 2. A recording apparatus for performing signal recording sectors, each comprising a plurality of full <br/> frame of the same number of bits in a recording medium as a unit, the synchronization pattern indicating the period of the frame and wards of the sector Means for generating a signal pattern indicating a break, a sector unit such that the synchronization pattern is arranged at the head of each frame, and the signal pattern is arranged adjacent to the synchronization pattern in the head frame of the sector. Means for formatting the data into a data string. From wherein a plurality of frames of each the same number of bits
A sector recording medium on which data is recorded in units of comprising, arranged said placed at the beginning of each frame, the synchronization pattern indicating the period of the frame, the synchronization pattern adjacent to the first frame of the sector A reproducing apparatus for reproducing a recording medium having a signal pattern indicating the division of the sector; a means for reading data recorded on the recording medium; and extracting the synchronization pattern from the read data. A reproducing apparatus comprising: means; means for extracting the signal pattern from the read data; and means for extracting the periodicity of the frame based on the extracted synchronization pattern. 4. The reproducing apparatus according to claim 3 , further comprising: means for extracting the periodicity of the sector based on the extracted signal pattern. 5. The reproducing apparatus according to claim 4 , further comprising means for controlling a demodulation timing of the data based on a periodicity of the extracted frame and a periodicity of a sector. Playback device. 6. The reproducing apparatus according to claim 4 , further comprising means for controlling a timing of writing the data to the memory based on the periodicity of the extracted frame and the periodicity of the sector. Characteristic playback device. 7. A plurality of frames each having the same number of bits.
On a recording medium on which data is recorded in units of
And is located at the beginning of each frame, and
Synchronization pattern indicating the cycle of the
Frame and adjacent to the synchronization pattern,
Recording medium comprising:
Reading the data recorded on the recording medium in the reproducing method for reproducing
When, to extract the synchronization pattern from the read data
A step that, to extract the signal pattern from the read data
And extracting the frame based on the extracted synchronization pattern.
Extracting the periodicity .
Playback method.