JPH02105371A - Digital data recording/reproducing device - Google Patents

Abstract

PURPOSE:To improve the correction ability to the continuous errors by storing the group data forming a group into a memory as the 2-dimensional data having its row number equal to an odd multiple of 4. CONSTITUTION:A control part 9 controls a data control part 6, a reinforcement code process part 7, and a data transfer part 8 via a communication part 4 based on the control information given from an external device. The part 6 stores the external digital data given from the external device into a memory 5 as a part of the 2-dimensional data. The part 7 performs a coding process of a 3rd error correction code and stores the redundant data into the memory 5 as a part of the 2-dimensional data. In this case, the row number of the 2-dimensional data is set equal to an odd multiple of 4 and therefore the code series of the 3rd error correction code never has the 2-byte data on the same track. Thus the correction ability is improved even to the continuous errors of an optional track.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a digital data recording and reproducing device that uses a tape as a recording medium and records digital data in units of group data, which is a predetermined amount of data. be.

Conventional technology In recent years, digital data recording and reproducing technology using magnetic recording and reproducing methods has made rapid progress, and its application development has progressed particularly in the digital audio field.
The draft standard for Audio Tape recorder has been standardized (THE DAT C0NF
ERENCE 5TANDARD/DIGITAL
AUDIOTAPERECORDERSYSTEM,
JUNE 1987), and it has now been put to practical use. A DAT records or reproduces digitized audio data by rotating a head with a positive azimuth angle and a negative azimuth angle to form continuous diagonal tracks on a magnetic tape. In addition, the signal processing performs error correction processing using a Reed-Solomon code combined with interleaving in units of frames consisting of two tracks, a plus azimuth track and a minus azimuth track. The Reed-Solomon code has two sequences, the 01 sequence with a code length of 32 and an inter-code distance of 5, and the 02 sequence with a code length of 32 and an inter-code distance of 7, and is used for code generation or error correction. Sufficient reliability for audio applications is achieved due to the error correction capability of this double de-Solomon code and interleaving, in which the data of each code sequence is evenly distributed and recorded within one frame on the tape.

On the other hand, attempts have been made to apply DAT as an external storage device for computers.

This is an attempt to realize a digital data recording and reproducing apparatus by recording and reproducing digital data transferred from a computer instead of digitized audio data.

Hereinafter, embodiments of the above-mentioned conventional digital data recording/reproducing apparatus will be described with reference to the drawings. FIG. 4 shows the configuration of the above-mentioned conventional digital data recording/reproducing apparatus. In FIG. 4, 1 is a tape which is a recording medium, 2 is a recording/reproduction processing unit that forms frames on the tape 1 and records digital signals, or reproduces the digital signals from the tape 1, and 3 is a device that complies with the DAT standard. This is a signal processing section that performs code processing and interleave processing based on the C1 series and 02 series, and exchanges the digital signal with the recording/reproduction processing section 2. 4 is a communication unit that transmits and receives control information and external digital data to be recorded and reproduced to and from an external device; 5 is a memory that temporarily stores digital data; 10 is a group consisting of a plurality of frames; This is a data management unit that forms group data in the memory 5 as two-dimensional data.

7 is an enhanced code processing unit that performs C3 processing, which is an enhanced code, on the group data formed on the memory 5; 8 is a data transfer unit that transfers the group data bidirectionally between the memory 5 and the signal processing unit 3; The units and 11 transfer data management information to the data management unit 10 according to a preset control procedure in accordance with the control information input via the communication unit 4, and also control the operation of the data management unit 10 and the enhanced code processing unit. 7 and the data transfer section 8.

The operation of the digital data recording and reproducing apparatus configured as described above includes a recording operation and a reproducing operation, and these operations will be explained below.

First, the recording operation will be explained.

When the control information given from the external device via the communication unit 4 indicates a recording operation, the control unit 11 generates data management information from the control information and transfers it to the data management unit 10. controls the transfer of the external digital data from the external device to the memory 5 via the communication section 4 based on the data management information. The data management unit 10 is
Group data included in the group is treated as two-dimensional data and processed in groups consisting of multiple frames. FIG. 5 shows the structure of the two-dimensional data configured on the memory 5 by the data management unit 10 This shows that. The data capacity of one frame is 5760 bytes, 1
The number of frames in a group is 26 frames, the number of rows of the two-dimensional data is 36, and the number of columns is 4139. The data management unit 10 stores the external digital data in a fifth
As shown in the figure, the data is recorded in the memory 5 as two-dimensional data of 32 rows and 4139 columns. When the storage of the external digital data is completed, the enhanced code processing unit 7 starts encoding processing of the third error correction code, which is the enhanced code. At this time, the code series is in the column direction of the two-dimensional data as shown by arrow I in FIG. 4139 sequences are generated up to the sequence . The redundant data generated by the above encoding process is 4 rows 4139 shown in FIG.
It is recorded in the memory 5 as two-dimensional data in columns. After the encoding process is completed, the data transfer unit 8 transfers the group data consisting of the external digital data and the redundant data to the fifth
As shown by arrow K in the figure, the two-dimensional data is sequentially transferred to the signal processing unit 3 in the row direction, and the signal processing unit 3 executes encoding and interleaving processing of the C1 series and C2 series based on the DAT standard, and the recorded signal is obtained. A digital signal is generated frame by frame, and the recording/reproducing process 12 records the digital signal onto the tape 1, thereby completing the recording operation. tape 1
The relationship between the track and frame formed above is shown in Figure 6.
FIG. 7 shows the relationship between frames and groups. 1 in Figure 6
A frame is composed of two tracks, a positive azimuth track and a negative azimuth track, and the signal processing unit 3 distributes the data for one frame to the two tracks based on the DAT standard. In Figure 7, one group is 26
The external digital data is composed of 22 frames shown in L, and 572 frames in 1 frame shown in M.
The above external digital data of 8 bytes and the above redundant data of 32 bytes are contained in two frames indicated by N, and the above redundant data of 5004 bytes and invalid data of 756 bytes are contained in one frame indicated by P. Each is recorded.

Next, the playback operation will be explained.

In the playback operation, the above recording operation is completely (reverse order) operation,
The recording/reproduction processing section 2 reproduces the groups formed on the tape 1, the signal processing section 3 performs deinterleaving processing, C1 series and C2 series decoding processing, and the data transfer section 8 stores the groups on the memory 5 as shown in FIG. Restore the two-dimensional data shown. The enhanced code processing unit 7 performs error correction processing from the arrow mark to the sequence shown by the arrow J in FIG. The data is transferred to the external device via the communication unit 4 and the playback operation is completed.

Next, the error correction ability of the third error correction code processed by the enhanced code processing section 7 will be explained.

Figure 8 shows the two-dimensional data shown in Figure 5 and tape 1.
This shows the correspondence with the frame above.

Further, FIG. 9 shows the arrangement of the 36-byte code series shown in Q in FIG. 8 on the tape 1. In Fig. 8, the number of columns of the two-dimensional data is set to 4139, which is coprime to the number of data in one frame, 5760, so the delimiters of each frame are sequentially shifted on the two-dimensional data, and therefore each code sequence is The data will be interleaved on tape 1. That is, the code sequence is appropriately distributed on the tape 1 as shown in FIG. Since the third error correction code has an intercode distance of 5, it has an error correction capacity of 2 bytes per code sequence, and - theoretically a maximum of 82 bytes per group.
It has a correction capacity of 78 bytes.

Therefore, as shown in FIG.
It is possible to correct continuity errors when errors occur in all data in one frame with good separation as shown by arrow S, and improve reliability for application to recording and reproducing computer code data, ASCII data, etc. We are trying to

Problems to be Solved by the Invention However, in the above conventional configuration, the signal processing section 3
In order to perform internal processing based on the AT standard, the types of tracks on which each data in one frame is recorded are periodic as shown by the 10 and 1 symbols in Figure 8, and the number of columns of two-dimensional group data is 413 disjoint to the number of frame data
9, the third error correction code includes a code sequence having 2-byte data contained in the same track, as shown by arrow T in code sequence Q in FIG. In other words, regarding continuity errors, arrow U in Figure 6
As shown in the figure, 2880 byte errors per track is the practical correction limit, and it is impossible to correct any two track errors, which is one-third of the theoretical correction ability calculated from redundancy. The problem was that it only had a certain degree of correction ability.

In view of the above problems, the present invention provides a digital data recording and reproducing apparatus that effectively arranges the code sequence of the third error correction code on the tape and has a high ability to correct continuity errors.

Means for Solving the Problems In order to solve the above problems, the digital data recording and reproducing apparatus of the present invention includes a data recording and reproducing means for recording or reproducing digital data by forming diagonal frames on a tape, and an interleaving process. a signal processing means for temporarily storing digital data; a storage means for temporarily storing digital data; a data management means for storing the data in the storage means, an enhanced code processing means for processing a Reed-Solomon code which is a third error correction code whose code sequence is in the column direction of the two-dimensional data; The structure includes a transfer means for performing bidirectional data transfer between the storage means and the signal processing means in data order in the row direction.

Effect The present invention uses the above-described configuration to reduce the number of columns of two-dimensional data to 4.
Since it is an odd multiple of , the code series of the third error correction code does not have 2-byte data on the same track, and the correction ability can be improved even for continuity errors in any track. .

Embodiments Hereinafter, embodiments of the digital data recording/reproducing apparatus of the present invention will be described with reference to the drawings.

FIG. 1 shows the configuration of a digital data recording/reproducing apparatus according to an embodiment of the present invention.

In FIG. 1, the same parts as in the above-mentioned conventional example are given the same numbers and their explanations will be omitted. 6 stores a group consisting of a plurality of frames as a unit, and stores the group data constituting the group as two-dimensional data in which the number of columns is an odd multiple of 4.
The data management unit 9 formed above transfers the data management information to the data management unit 6 according to a preset control procedure in accordance with the control information input via the communication unit 4, and also controls the operation of the data management unit 6. and a control section that controls the operation of the enhanced code processing section 7 and the operation of the data transfer section 8.

The operation of the digital data recording/reproducing apparatus configured as above will be explained below.

In the recording operation, the control section 9 controls the data management section 6, enhanced code processing section 7, and data transfer section 8 according to control information received from an external device via the communication section 4. The data management unit 6 records the external digital data provided from the external device in the memory 5 as part of the two-dimensional data, and the enhanced code processing unit 7 performs encoding processing with a third error correction code to remove the redundant data from the above. Memory 5 as part of 2D data
to be memorized. FIG. 2 shows the structure of the two-dimensional data stored in the memory 5. As shown in FIG. In Figure 2, the above 2
The number of columns 4140 of the dimensional data is 4140=4X1035, which is set to an odd multiple of 4. The external digital data is 2-dimensional data with 32 rows and 4140 columns, and the redundant data is 2-dimensional data with 4 rows and 4140 columns. It is stored in the memory 5 as dimensional data.

The data transfer unit 8 sequentially transfers the external digital data and the redundant data to the signal processing unit 3 in the row direction shown by arrow A in FIG. digitization and interleave processing to generate a digital signal, which is a recording signal, frame by frame.
The recording/reproduction processing section 2 records the digital signal onto the tape 1, thereby completing the recording operation.

In the playback operation, the operation is completely reversed to the above recording operation.
The tape 1 is played back, and the recording and playback processing section 2, the signal processing section 3,
The enhanced code processing unit 7 performs error correction processing on the two-dimensional data shown in FIG. 2 restored on the memory 5 by the operation of the data transfer unit 8, and the data management unit 6 The necessary external digital data is transferred to the external device via the communication section 4, and the playback operation is completed.

Next, the error correction ability of the third error correction code will be explained. In this embodiment as well, the third error correction code has an inter-code distance of 5, so it has an error correction capacity of 2 bytes per code sequence, and the theoretical maximum correction capacity per group is 8280 bytes. FIG. 3 shows the arrangement of the 36-byte code series shown in B in FIG. 2 on the tape 1.

As shown in Figure 2, the number of columns of the two-dimensional group data is set to 4140, which has only the least common multiple of 2 and the number of data in one frame, 5760, that is, a number with a small correlation, so the delimiter of each frame is set to 2. There is a sequential shift on the dimension group data, so each code sequence is interleaved on the tape 1 as shown in FIG. Also, one frame consists of two types of tracks, a positive azimuth track and a negative azimuth track, but since the signal processing unit 3 performs internal processing based on the DAT standard, one
The type of track on which each data in a frame is recorded is periodic with an 8-byte period as shown by the 10th symbol and 1st symbol in Figure 2, and the 8-byte period above is divided into the first 4 bytes shown in C and D The latter 4 bytes shown are symmetrical. Here, the number of columns of the two-dimensional data is 41, which is an odd multiple of 4.
40, so when one code sequence has two data belonging to the same frame as shown by E and F in FIG. 2, the two data E and F belong to mutually different tracks. That is, as shown in FIG. 3, all the above code sequences are always composed of data of different tracks. Therefore, it is possible to correct not only data errors caused by large scratches on the tape 1 as shown by arrow G in FIG. 3, but also continuous data errors on arbitrary two tracks as shown by arrow H. This means that regarding continuity errors, a high correction ability that is more than two-thirds of the theoretical maximum correction ability has been achieved.

As described above, according to this embodiment, the recording/reproduction processing section 2, the signal processing section 3, the memory 5, the data management section 6, and the enhanced code processing section 7 are provided, and the two-dimensional By processing the data, it is possible to realize a high correction capability not only for scratches on the tape 1 but also for continuity errors in track units. In other words, high data reliability can be obtained even in the face of practical problems such as head clogging of the DAT mechanism.

Effects of the Invention As described above, the digital data recording and reproducing apparatus of the present invention includes a data recording and reproducing means for recording and reproducing digital data by forming a frame, a signal processing means for interleaving, and a data recording and reproducing means for recording and reproducing digital data by forming a frame, a signal processing means for interleaving, and a data recording and reproducing device for recording and reproducing digital data in groups. is 4
a data management means configured as two-dimensional data that is an odd multiple of , a storage means for temporarily storing the digital data, an enhanced code processing means for performing code processing, and a data processing means for transmitting the digital data to the signal processing means. By providing a transfer means, the code series of the above-mentioned enhanced code does not have two or more pieces of data on the same track, and achieves an extremely high correction ability not only for scratches on the tape but also for continuity errors on a track-by-track basis. It is something that can be done. In other words, it is possible to easily realize a highly reliable digital data recording/reproducing device by using the mechanism of an audio DAT and a signal processing circuit, and the effect is great.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a digital data recording and reproducing apparatus in one embodiment of the present invention, FIG. 2 is a structural diagram of two-dimensional data formed on the memory 5 in this embodiment, and FIG. 3 is a similar diagram. FIG. 4 is a configuration diagram of a group formed on tape 1; FIG. 4 is a configuration diagram of a conventional digital data recording/reproducing device; FIG.
The figure is a structural diagram of two-dimensional data formed on the memory 5 in a conventional example, FIG. 6 is a configuration diagram of a frame, FIG. 7 is a configuration diagram of a group similarly formed on the tape 1, and FIG. is a diagram showing the relationship between the two-dimensional data shown in FIG. 5 and the above frame, and FIG. 9 is a diagram showing the distribution of code sequences on the tape 1. 1... Tape, 2... Recording/playback processing section, 3
...Signal processing section, 4...Communication section, 5...
Memory, 6゜10... Data management unit, 7... Enhanced code processing unit, 8... Data transfer unit, 9.11.
...Control unit.

Claims (1)

[Claims] a data recording and reproducing means for recording and reproducing digital data by forming diagonal frames on a tape; a signal processing means for performing interleaving processing; a storage means for temporarily storing digital data; and a plurality of the frames. data management means for storing data to be recorded and reproduced in said group as two-dimensional data whose number of columns is an odd multiple of 4 as a management unit; an enhanced code processing means for encoding and decoding a Reed-Solomon code; and a transfer means for performing bidirectional data transfer between the storage means and the signal processing means in data order in the row direction of the two-dimensional data. A digital data recording and reproducing device comprising: