JP2563466B2 - Digital signal recording / reproducing device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape digital data recording / reproducing apparatus.

2. Description of the Related Art Conventionally, a magnetic tape device for data recording has a structure in which the names, identification numbers, recording position information, etc. of files recorded on the tape are collectively recorded as an index. However, in recent years, it has been only partially seen that the configuration is made in another format having index (or directory) information.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the configuration having the index portion, the index portion is frequently accessed because the index portion is frequently accessed, and there is a concern in reliability. If a part of this index part becomes unreadable, the data of the entire tape cannot be used in the worst case.

In view of the above problems, the present invention restores the index information based on the information previously recorded in the auxiliary recording section of the file data recording section even if the index information cannot be read, and the deterioration of the tape It is an object of the present invention to provide a digital signal recording / reproducing apparatus capable of recording index information in a non-existing portion.

Means for Solving the Problems In order to solve the above problems, a digital signal recording / reproducing apparatus of the present invention is a file for recording file management information in an auxiliary recording section of a file data section on a tape when recording file data. The data recording / reproducing means and part or all of the file management information of each file recorded on the tape are collectively recorded at a predetermined position on the tape as an index, and an area required for the index information is set at a predetermined position. An index recording / reproducing means secured in the above, a file management information control section for controlling the file data recording / reproducing means and the index recording / reproducing means, a recording section for temporarily storing reproduced data,
File data end detecting means for detecting the end of the file data recorded on the tape, error correcting means for performing error correction processing on the reproduced data, and data recorded by receiving the error correctability information output from the error correcting means. And a recorded data check means for checking whether or not is recorded correctly.

Operation According to the present invention, with the above configuration, the tape information is sequentially read from the beginning of the tape to the end of the recorded data, and the index information is obtained based on the information previously recorded in the auxiliary recording section of the file data recording section. It can be restored.

EXAMPLE An example in which the digital signal recording / reproducing apparatus of the present invention is applied to a rotary head type magnetic recording / reproducing apparatus will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a digital signal recording / reproducing apparatus according to an embodiment of the present invention. The present embodiment is applied to a so-called R-DAT type digital signal recording / reproducing apparatus for rotating two heads having different azimuth angles to form diagonal tracks on a tape and recording digital data.

In FIG. 1, 1 is a cassette half, 2 is a reel,
3 is a tape, 4 is a cylinder, 5a and 5b are recording / reproducing heads,
5c and 5d are reproducing heads for checking recorded data, which are included in the mechanism section 6. Reference numeral 7 is a mechanism control unit for controlling the operation of the mechanism unit 6, and 8 is connected to the heads 5a, 5b, 5c, 5d to send a recording signal or receive a reproduction signal, and convert data and a recording signal and perform error correction processing. An input / output device 9 for receiving data from a host system (not shown) and sending reproduced data to the host system, and a data processor 10 for inputting data to the input / output device 9 8 is a storage unit for temporarily storing data for delivery to and from 8, and 11 is a recording unit for recording the file data on the tape and the data to be recorded in the auxiliary recording unit such as file management information
A file data recording / playback control unit that sets 10 and issues a recording instruction, and separates and reads the file data and auxiliary recording data from the played data, and 12 is a part of the file management information of each file recorded in the tape. Alternatively, it is an index recording / reproduction control unit that controls recording and reproduction of all of them as an index at a predetermined position on the tape. The file data recording / reproducing control unit 11 and the index recording / reproducing control unit 12 are included in the file management information control unit 13. The mechanism control unit 7, the input / output device 9, and the file management information control unit 13 are connected to and controlled by a system control unit 14 that controls the entire digital signal recording / reproducing device. Reference numeral 15 is a recording data check unit that receives the error correction enable / disable information output from the signal processing unit 8 including an error correction unit and checks whether the recorded data is correctly recorded and outputs an error signal to the file management information control unit 13. Indicates the end of the file data recorded in the auxiliary recording part of the tape.
e) A file data end detection unit that detects information and outputs an end signal to the file management information control unit 13.

FIG. 2 is a diagram showing in which area each data is recorded when recording is performed by the digital signal recording / reproducing apparatus according to the present embodiment. Originally, the track is formed obliquely with respect to the tape running direction, but here it is simplified as shown in the figure. The file data area occupies most of the tape, file data is recorded in the main data area (file data recording area), and the sub data area (auxiliary recording area)
File management information and the like are recorded in. An index portion is secured near the beginning of the tape, and information for file management recorded on this tape is recorded. An EOT area is provided at the end of the data, indicating that the data has not been recorded thereafter. In the auxiliary recording section, the file name, file creation date and time, file attribute, frame position information (information about the frame number from the beginning of the tape), information indicating the beginning or end of the file, EOT Information that indicates an area is included. The name of each file, the creation date and time, the head frame number of the file, and the like are recorded in the index section.

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

The digital signal recording / reproducing apparatus in this embodiment receives data from the host system, records it on a tape, reproduces it, and sends the data to the host system. First, basic recording / reproducing of data will be briefly described.

An instruction is issued from the system control unit 14 by turning on the power or setting a tape, and the management information regarding the files recorded so far is read from the index unit and stored in a part of the storage unit 10 in advance. Next, the data sent from the host system is received by the input / output device 9 and stored in the recording unit 10. When a certain amount of data is accumulated, the system control unit 14 issues a command to the file management information control unit 13. For example, when adding file E,
Since it is known from the index information that the file should be added after the file D, a deep is sent to advance to the beginning of the EOT. At that time, since the absolute frame number is recorded in each sub-data area of each frame or track, by performing the same process as the high-speed search of the audio DAT, the tape number is read while reading the frame number in the sub-data area. The tape can be fast-forwarded, and the tape can be quickly fed at the target position or position. Then, the information (file name etc.) to be recorded in the auxiliary recording section of the file data is set in the storage section 10 and sent to the signal processing section 8 together with the file data, and after the processing such as addition of an error correction code and modulation, the head is processed. It is output as a recording signal to 5a and 5b. At the same time, the system control section 14 gives an operation instruction to the mechanism control section 7 as a recording mode, and the mechanism control section 7 controls the reels 2 and the binder 4 to run the tape 3 and record data on the tape. After that, the index information stored in the storage unit 10 is updated based on the management information of the newly added file E, the tape is rewound, the index information is recorded in the index unit, and the index information on the tape is also updated. Keep it.

In the case of reproduction, the system control unit 14 receives a read instruction and a file name designation command from the host system through the input / output device 9, reads the head frame number of the corresponding file from the index information, and sends the tape to that position. Heads 5a and 5b that perform playback operation from that
The data recorded on the tape 3 is sequentially read out, and is converted into the original data by the signal processing unit 8 and stored in the recording unit 10. The stored data is sequentially sent to the host system through the input / output device 9. The above is the basic operation, and the point which is the point of the present invention will be mainly described below.

As described in the basic recording operation described above, the index section has to be rewritten and updated each time one file is recorded, and the number of accesses to the index section greatly increases. In order to reduce the number of times the index section is accessed, there is a method in which the index is not updated each time the file is rewritten, but is performed each time the batch processing is completed or each time the tape is taken out. Although it may be useful to use these methods from the viewpoint of improving reliability, it cannot be denied that the index part has a higher access count than the file data part. That is, the index portion of the tape is likely to deteriorate quickly, and there is a high possibility that the index portion cannot be read first. Or, if the user mistakenly turns off the power before updating the index, the tape cannot be used properly from the next time.

Also, consider the case where a part of the tape is scratched for some reason. If the damage is in the file data part, only one file becomes unreadable, but if the index part is damaged, the correspondence between the file name and the recorded position information will be unknown, and in the worst case The file on the entire tape becomes unreadable.

Conventionally, it was fatal if the above things happen,
According to the present invention, the index portion can be restored correctly and does not hinder the subsequent use.

First, it is necessary to record information including the contents of the index part in the area of each file data part. In this embodiment, it is recorded in the auxiliary recording section. FIG. 3 shows an example of information recorded in the auxiliary recording section. When reading out the index portion, if the error correction portion in the signal processing portion 8 finds that the data is incorrect and cannot be corrected, the signal processing portion 8
Then, the uncorrectable signal (a) is output to the recording data check unit 15. The recording data check unit 15 receives it and sends an error signal (b) to the file management information control unit 13.
Is output. The file management information control unit 13 that has received the error signal (b) shifts to the index restoration processing. The shift to the index restoration process can be performed by a command from the host system. First, the data in the file data section is read in the playback mode from the beginning of the tape, and the information (file name, creation date and time, file attributes, etc.) necessary for the index recorded in the auxiliary recording section is collected for each file. It is stored in the storage unit 10. FIG. 4 shows an example of information recorded in the index section. When the information indicating the beginning of the file is found, the frame number with that information is set as the leading frame number of the file.
To store. When the EOT area is reached, the EOT information recorded in the auxiliary recording section is detected by the file data end detection section 16 and the end signal (c) is output to the file management information control section 13. Upon receiving this, the file management information control unit 13
A mechanism stop designation is issued, then the tape is rewound to the index section, and the file management information stored in the recording section 10 is recorded in the index section. In this embodiment, the read-after-write method is adopted, and the contents recorded on the tape by the preceding heads 5a and 5b are read by the follow-up heads 5c and 5d,
Immediately after recording, it is possible to check whether or not it was recorded correctly. The check method by the recording data check unit 15 includes a method of using an uncorrectable signal of an error correction unit in the signal processing unit 8 and a method of comparing recorded contents and read contents in the storage unit 10 at the time of recording. is there. If the index is restored when the index is not updated due to an incorrect use by the user, the index can be restored correctly with this. However, if the deterioration of the tape is the reason why the index section could not be read, the index cannot be recorded correctly at the same location as the previous time. In that case, that is, if the error signal (b) is output from the recording data check unit 15 during the index recording,
Record the index elsewhere without tape deterioration.
The area for newly recording the index is set to a position where the tape is advanced by a predetermined amount (for example, 5 frames ahead) from the index portion where the error has occurred, by securing a sufficient area on the tape as the index portion in advance. To do. If the data cannot be recorded correctly even at that position, the index is recorded at the position where the 5-frame tape is advanced. By securing a sufficient area on the tape as the index portion, the system can fully fulfill its role even if it becomes partially unusable. Here, there will be multiple index information in the index section, but if the empty area of the index section is filled with empty information when the tape is first formatted, the latest index information will be the one before the empty information. I know there is.

The mechanism control unit 7, the file data recording / reproduction control unit 11, the index recording / reproduction control unit 12, the file management information control unit 13, the system control unit 14, the recording data check unit 15, the file data end detection unit 16, etc. It is also possible to integrate some of them and configure them with a microcomputer.

Effect of the Invention As described above, the present invention can restore index information based on the information already recorded in the auxiliary recording section of the file data recording section even when the index section cannot be read correctly. In addition, when the index information cannot be correctly recorded at the position where the index information is to be recorded due to the deterioration of the tape or the like, the index information can be recorded at another position where the tape is not deteriorated, and the reliability of the system is greatly improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a digital signal recording / reproducing apparatus in an embodiment of the present invention, FIG. 2 is a diagram showing which area on the tape each data is recorded, and FIG. 3 is an auxiliary recording. FIG. 4 is a diagram showing an example of information recorded in the section, and FIG. 4 is a diagram showing an example of information recorded in the index section. 1 ... cassette half, 2 ... reel, 3 ... tape,
4 ... Cylinder, 5a, 5b ... Recording / playback head, 5c, 5d ...
Playback head, 6 Mechanism unit, 7 Mechanism control unit, 8 Signal processing unit, 9 Input / output device, 10
Storage unit, 11 …… File data recording / playback control unit, 12 ……
Index recording / playback control unit, 13 ... File management information control unit, 14 ... System control unit, 15 ... Record data check unit, 16 ... File data end detection unit.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masao Okabe 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-60-167184 (JP, A)

Claims (1)

(57) [Claims] Claim: What is claimed is: 1. A digital signal recording / reproducing apparatus for recording and reproducing on a single tape a plurality of files in which logically connected data are collected, which is on a tape when recording file data. File data recording / reproducing means for recording the file management information in the auxiliary recording part of the file data part, and part or all of the file management information of each file recorded on the tape are collectively used as an index at a predetermined position on the tape. Index recording / reproducing means for recording and securing an area necessary for index information at a predetermined position, a file management information control section for controlling the file data recording / reproducing means and the index recording / reproducing means, The storage part for temporarily storing data and the end of the file data recorded on the tape are detected. Means for detecting the end of the fail data, an error correcting means for performing an error correction process on the reproduced data, and a recorded data check for checking whether or not the recorded data is correctly recorded by receiving the error correction enable / disable information output from the error correcting means. Means for sequentially reading the management information about all files recorded on the tape from the auxiliary recording section of the file data recording section, storing at least the data required for the index in the above storage section, and storing these data in the tape. It is configured to record as an index at a predetermined position, and after recording the index information, when it is determined by the recording data check means that the index information is not correctly recorded, the index is recorded at another preset position. A digitizer characterized by being configured to record information Signal recording and reproducing apparatus.