JPH02282978A - Recording and reproducing method for data recorder - Google Patents

Abstract

PURPOSE:To immediately take out a required data at the time of reproducing by recording a block mark (BM) in a completing position whenever every data is completed in its recording and recording a table for management of the BMs within one group in an area of contents. CONSTITUTION:At the time of recording a data on a tape, the data and data length are transferred from a host computer to an input and output device 17 to be decoded by a command circuit 18. When data by one group is stored in a data buffer memory 19, the data is recorded in a main data area, and at the same time, BM members are recorded in a system area. The BM member at the lead of each data in the group is stored in a block mark table memory 23, and the data is written in a class information area (CI) just prior to unloading the tape. At the time of reproducing, a desired block member to read out is transferred from the host computer to the input and output device 17, and a group member is retrieved from the BM table read out of the CI, and then the block length is calculated, and hence its group is reproduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Industrial Application Field The present invention is directed to signal recording and reproduction for use, for example, in a rotary head type digital audio recorder (R-DAT) as a storage device (data recorder) of information equipment. Regarding the method.

(B) Conventional technology Conventionally, in R-DAT, an information recording area for recording digitally converted music signals is formed in the center of the trace of each track of a tape that is helically scanned by a rotating head, and the information recording area for recording digitally converted music signals is A subcode area is formed on both sides of the recording area, that is, at the trace start end and the trace end of each track, together with a tracking area (ATF area). In this tracking area, a servo signal for tracking control is recorded, and in the subcode area, information such as a start I'D indicating the beginning of a song along with the song number and time information are recorded.

However, recently, it has been considered to use such R-DAT as a storage device for information equipment; for example, 120
R-DAT, which uses minute tapes, can achieve a storage capacity of about IGBytes, making it a low-cost, large-capacity, and small-space recording device compared to the conventional MT wave device hard disk device used as a storage device. can be provided.

In addition, with a data recorder that uses R-DAT as a storage device for information equipment, two tracks can be treated as one frame, and more! There is a method for recording and reproducing in groups of &7 frames as one group, which was submitted by the present applicant on October 31, 1981 (Japanese Patent Application No. 63-2754).
No. 71).

Note that the data recorder divides this group into a plurality of blocks and records a plurality of files. Also,
For hard disk devices, the block length is, for example, 16K,
32 byte fixed length (K=2I@).

(c) Problems to be Solved by the Invention However, with a data recorder that records with a fixed block length as in the conventional example, even when recording file data with a capacity much smaller than the capacity of one block, it is possible to record in blocks. Therefore, after recording a file with a small capacity, meaningless data must be recorded up to the end of the program, increasing tape consumption.
A problem has arisen in that time is taken to record this meaningless data.

(d) Means for Solving the Problems In order to solve the above problems, the present invention records digital signals on a tape that is helically scanned by a rotating head, with two tracks as one frame and a plurality of frames as one group. In a data recorder that records data in groups, the data is recorded in the data area at the time of recording, and each time a complete data recording is completed,
A block mark is recorded at the end position of the completed data in a system area separate from the data area, and a table for managing the first block mark in one group is recorded in the table of contents area at the beginning of the tape. Search for the block mark indicating the start position of the necessary complete data and the next data block from the contents of the table of contents area,
A recording and reproducing method for a data recorder is proposed, which is characterized in that the variable data length of the necessary complete data is determined by calculation and the data is reproduced.

(E) Effect According to the above means, since the block length is variable, the data length becomes equal to the block length, so variable length data can be recorded sequentially from the beginning of the tape, and the necessary data can be recorded during playback. can be taken out immediately.

(f) Example An embodiment of the present invention will be described below with reference to the drawings.

According to the digital signal recording and reproducing method of the present invention, recording is performed in groups, with two tracks as one frame and a plurality of frames (for example, 32 frames) as one group, and interleaving is performed in frame units. together with the first and second check codes (C
I) (CI), and it is possible to select the addition of a tertiary check code in group units. Also, during playback, de-interleaving is performed in frame units, and check codes (CI) are added in track units. C,)(C,)
If a tertiary check code is selected, error detection and correction is performed using that check code. Next, an example of the system configuration of this embodiment will be explained using FIG. 1. That is, in the figure (1) is a mechanism with the same configuration as the R-DAT for audio, and the mechanism (1) is provided with a rotating cylinder capstan motor, a reel motor, etc. (2).
) is a recording/playback amplifier that sends and receives recording and playback signals between two recording/playback rotary heads (heads A and B) placed 180° apart on a rotating cylinder, and (3) records in l-frame units. Sometimes the first and second check codes are added (C, , C
, ), an intra-frame signal processing circuit that performs interleaving, etc., and performs error detection and correction using check codes during playback, and de-interleaving, etc. (4) adds a tertiary check code during recording in units of l groups, and during playback. The intra-group signal processing circuit (4) is configured as shown in FIG. 2, and is an intra-group signal processing circuit that performs error detection and correction using check codes. That is, (5) is an error correction circuit that adds a check code during recording in units of one group and performs error detection and correction using the check code during playback, and (6) is an error correction circuit that interleaves data during recording in units of one group. (7) and (8) temporarily store data sent from the host computer in groups during recording (save) and play it back from the tape during playback (loading). The data stored in the first group memory (7) is stored in the first and second group memories in the first and second group memories temporarily in one group.
This is done while the data is being supplied to the intra-frame signal processing circuit (3) via the interface circuit (9) with the error correction code added from 5). Note! / reading will be performed alternately. (10) is controlled by the system control circuit described later. 2nd group memory (7) (8)
A control circuit that controls the error correction circuit (5) and interleave address generation circuit (6), and adds check codes to the data read from the first and second group memories (7) and (8) in groups during recording. and when playing back *i, 2nd group memory (7) (8)
The interleaving address generation circuit (6) performs de-interleaving on the data that has been previously stored and subjected to error detection and correction by the error correction circuit (5) in group units. (11) is a cylinder servo circuit that drives and controls the rotating cylinder, (12) is a reel servo circuit that drives and controls the reel motor, (13)
(14) is a capstan servo circuit that drives and controls the capstan motor, and (14) is an intra-frame signal processing circuit (
AT that extracts the signal in the ATF region from the output of the recording/playback amplifier (2) through 3) and generates a tracking error signal.
In the F circuit, this error signal is sent to the capstan servo circuit (
13) and used to control the rotational speed of the capstan motor. (15) is a subcode processing circuit that extracts a subcode region signal from the output of the recording/reproducing amplifier (2) through the intraframe signal processing circuit (3) during playback;
) is operated by the input of various operation keys manually, the output from the subcode processing circuit (15), or the output from the command circuit (to be described later). ), a reel servo circuit (12), and a capstan servo circuit (13). (17) is an input/output device that serves as an input/output terminal to the host computer, and (18) is a system control circuit (16) that responds to instructions from the host computer through this input/output device (17).
), and the command circuit (18) is configured as shown in FIG. That is, (19) is a data buffer memory that temporarily stores data sent from the host computer during recording (save) and temporarily stores data reproduced from the tape during playback (loading), and (20) is a data buffer memory that temporarily stores data sent from the host computer during recording (save). An instruction decoding circuit (21) decodes and outputs the decoded data to a control circuit (described later);
), block mark table memory (23), and system control circuit (16).
9) and the first and second group memories (7) and (8). Next, the operation of such a system configuration example during recording will be described.

The group structure of the present invention is as shown in Fig. 4 in the margin area (5
4) (55) (56), data area (52) (53), and puffy area (51). Furthermore, data area (52) (53) is a main area consisting of 5120 bytes as shown in Figure 5. It is formed from a data area (M) and a system data area (S) consisting of 92 bytes. Data input from the host computer is recorded in the main data area (M), and the system data area IJi (S) is marked with block marks shown in FIG. (representing the cumulative number of bytes at the location) is stored. In addition, the main data area (M) and the system data area jJi (S) constitute one unit, and 32 units constitute one group of data areas (52
)(53). In addition, in the present invention, since the block length is made variable, the data length of the completed data is equal to the block length.

Therefore, when recording data on tape with this device,
Data and its data length are transferred from the host computer to the input/output device (17) and decoded by the command circuit (18). When the data for one glue is stored in the data buffer memory (19), the data is recorded in the main data area (M) and the block mark number is recorded in the system area (S).

The first block mark number in the group is stored in the block mark table memory (23) as shown in FIG. 7, and the data in this memory (23) is stored in the data area at the beginning of the tape as shown in FIG. It is written to the class information area (CI) other than (DA) immediately before unloading the tape.

Next, when playing back the tape recorded as above, the block number you want to read from the host computer is in the input/output field!
(17) and recorded at the beginning of the tape when loading the tape.
) is searched for the group number (N) in which the block number (B) exists. Then, the group number (G) in which the next block number (B+1) exists is searched.

After that, quickly search the G group and store the main data and system data of the G group in the data memory (19).
, store the block mark (B M ) of (B+1) block from the system data, and similarly store N
Search the group, read the data, and store the block mark (BKM) of the B block.

From the above, the data length of one block in which complete data is recorded can be calculated for each case as follows. ■The amount of data that can be recorded in a group is 128
I have a part-time job.

i) When one block length is completed within one group, data length of one block = (BM) (BKM)c
Paitco 1i) When one block length is recorded over two groups, l block data length = (BM) + (128 -
BKM) [Paitoco 1ii) When one block length is recorded over three groups or more, the data length of one block = 128KX (G-N-1)
+BM+ (128K -MKM) [Paitoco] Calculates the data length of one block using the above calculation formula, reproduces the group that includes that l block, reads data for one block length, and transfers it to the host computer.

(G) Effects of the Invention According to the present invention, since the block length can be varied according to the data length, it is possible to record data on the tape without any gaps, reducing waste of tape, and search operation is also faster than the conventional fixed length. It can shorten the time required for recording as much as it can. Furthermore, since the block length can be matched to the block length of the external storage device, compatibility with the external storage device can be obtained, making it extremely suitable for use in a data recorder using R-DAT.

[Brief explanation of drawings]

1, 2, and 3 are block diagrams showing the configuration for realizing the method of the present invention, FIGS. 4 to 8 relate to the present invention, and FIG. 4 is a diagram showing a group format, and FIG. Figure 5 shows the data area in detail, Figure 6 shows the contents recorded in the system data area, Figure 7 shows the contents recorded in the class information area, and Figure 8 shows the contents recorded at the beginning of the tape. FIG. 3 is a diagram showing a recording state. (M)...Data area (main data area), (S)
...System area (system data area), (CI)
...Table of contents area (class information area). Figure 5 Figure 6

Claims (1)

[Claims] (1) In a data recorder, recording of digital signals on a tape that is helically scanned by a rotating head is performed in groups, with two tracks as one frame and multiple frames as one group. is recorded in the data area, and a block mark is recorded in the system area separate from the data area at the end position of the completed data each time recording of the completed data is completed, and the first block mark within one group is managed. A table is recorded in the table of contents area at the beginning of the tape, and during playback, the block mark indicating the start position of the necessary complete data and the block mark of the next data are searched from the contents of the system area and table of contents area, and the block mark of the next data is searched for. A recording and reproducing method for a data recorder, characterized in that the variable data length of complete data is determined by calculation, and the data is reproduced.