JPH01154384A - Data recording and reproducing system for rotating head type tape recorder - Google Patents

Abstract

PURPOSE:To improve a reliability on contents information by previously recording the latest contents information on a main contents memory on the contents area of a tape and recovering the contents information by a sub-contents memory even when the contents information of the main contents memory is lost owing to a power failure or the like. CONSTITUTION:Before the eject operation of a cassette, the latest contents information of the main contents memory 16 is stored in the contents area of the tape. When a power is interrupted according to the power failure or the like, the latest contents information on the memory 16 is lost and the contents area of the tape cannot be rewritten. The generation of such an abnormal situation is detected according to the presence or absence of the cassette at the time of charging the power, a next recovery is executed based on the information remaining in a ROM. The contents information stored in the contents memory 20 is loaded to the main memory 16 from the tape, the memory 16 is changed based on the change history of the contents infor mation remaining in the memory 20 and thereafter, the contents information changed in the memory 16 is recorded in the contents area of the tape and recovered to the contents information before the generation of the abnormal situation.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to a data recording and reproducing method for using, for example, a rotary head digital audio tape recorder (R-DAT) as a storage device for information equipment. be.

(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 tracking area (ATF area) and a subcode area are formed on both sides of the recording area, that is, at the trace start end and the trace end of each track. A servo signal for tracking control is recorded in this tracking area, and a start ID indicating the beginning of the song is recorded in the subcode area along with song number and time information.
etc. were 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 storage device with a lower price, larger capacity, and smaller space than the conventional MTi storage devices and hard disk devices. can be provided.

Specifically, when such an R-DAT is used as a storage device for information equipment, its track format is compliant with audio, and programs and digital data are recorded in place of music signals in the aforementioned information recording area. However, if multiple programs and digital data were recorded sequentially from the beginning of the tape to the end in the same way as when recording music signals,
There is a problem in that the responsiveness when reading a program or digital data after recording is extremely poor compared to a disk device. In addition, when recording a program or digital data, you can easily find out to what part of the tape recording has ended, where the recordable part that occurs due to partial erasure after recording is located, and what its capacity is. There wasn't.

For this reason, in R-DAT, for example,
A device as shown in Publication No. 258786 (GIIB 27/10) has been considered. Such conventional technology includes a table of contents information storage means for storing table of contents information having one or more sets of information regarding the recorded signal, such as a recorded signal name such as a number that can be transferred to music, and the start and end count values of the signal, and a table of contents information storage means. It has a table of contents information tape recording means for recording the table of contents information in the means on the tape, and a table of contents information reading means for importing the table of contents information recorded on the tape into the table of contents information storage means, and when the tape is ejected, the table of contents information is read immediately. Without ejecting, the table of contents information in the table of contents information storage means is recorded on the tape by the table of contents information tape recording means, and then the tape is ejected, and when the tape is attached, it wraps up to the top of the table of contents information recorded at the time of ejection. The table of contents information is loaded into the table of contents information storage means by the table of contents information reading means, and the table of contents information is used to realize a quick song selection operation.
By configuring the table of contents information in the table of contents information storage means to hold it, it is possible to prepare for unexpected situations.

(c) Problems to be Solved by the Invention In the above-mentioned conventional example, the purpose is to select songs from the music information recorded on the tape, and the table of contents information includes the song number, start and end count values, etc. Each recording takes about 10 to 20 bytes at most, and even if 20 songs are recorded on one tape, it will take up only 400 bytes, which is extremely small. or,
Normally, once music information is recorded, it is almost never re-recorded, and therefore table of contents information rarely changes.However, in the storage devices of information devices, tens of thousands of files and programs are recorded on a single piece of tape. Since the table of contents information alone is 1M byte, a lot of power is required for backup when the power is cut off, and the circuit size is also large, making it difficult to utilize conventional technology as is.

(d) Means for solving the problems In order to solve the problems of the above-mentioned prior art, the present invention provides the following:
A rotary head type tape recorder that forms a data area and a table of contents area for recording table of contents information of files recorded in the data area on a tape that is helically scanned by a rotary head, the table of contents area A first storage means for storing the table of contents information recorded in the Tt source, and a second storage means for storing the change history of the table of contents information changed by writing and erasing files, and the second storage means stores the table of contents information recorded in the Tt source. It is structured so that the memory contents are retained even if the computer is turned off.

(E) Effect According to the data recording/reproducing method of the present invention described above, even if an unexpected situation such as a power outage occurs, the power outage is automatically performed based on the change history of the table of contents information stored in the second storage means. The previous table of contents information can be reproduced.

(F) Example Hereinafter, an example of the present invention will be described with reference to the drawings. That is, according to the data recording and reproducing method of the present invention, the area between the beginning and the end of the tape is divided into a plurality of areas, and a table of contents area is provided at the beginning of each divided area to record the table of contents of the files recorded in each divided area. When recording files on each track in the data area except the table of contents area, multiple frames (8 frames in the present invention) are divided into sectors in units of 2 tracks/tracks. This is what I decided to do. Hereinafter, this divided area will be referred to as a class, and the table of contents area will be referred to as a TOC (table o
In this invention, the division management method in which the beginning and end of the tape is divided into a plurality of classes and used is referred to as "one class format". Specifically, Figure 1 shows the case where a 120-minute tape is divided into 8 classes at equal intervals.
As shown in the figure, file data is recorded in the information recording area of each track, and a class number, a sector number, an information identification signal indicating whether it is a TOC area or a data area, etc. are recorded in the subcode area. Further, in the TOC area of each class, table of contents information, which will be described later, is recorded in the information recording area of each trunk, and the same information as the subcode area of the data area described above can be recorded in the subcode area.

Note that the remaining areas of each track, such as the ATF area, conform to the audio DAT format.

Next, regarding the table of contents information recorded in the TOC area, the third
This will be explained with figures. There are 5 main areas in the TOC area.
control table, directory entry table, sector map, BAD sector map,
The sector code is recorded. The control table records the tape type and the number of TOC divisions, the directory entry table records the root directory names of files recorded in the data area, and the sector map and BAD sector map each record each sector in the data area. The situation and sectors in which recording and playback are impossible are recorded. Further, the sector code is sector management information, and the file name, file size, etc. of each sector of the data area are recorded in order from the first sector. The sector hood is 1
Each sector consists of 32 bytes, and if a 120-minute tape is used in one class without being divided, there will be 30,400 sectors of data recorded in the data area, so the maximum size of the sector hood will be about IM bytes. .

Next, in Fig. 0, an example of a system configuration for realizing the data recording/reproducing method of the present invention will be explained in conjunction with Figs. 4 and 5.
The mechanism has the same structure as (1), and a rotating cylinder, a capstan motor, a reel motor, and a tape start/end sensor (2) are arranged in the mechanism (1). (3) is a recording/reproducing amplifier that sends and receives recording/reproducing signals to and from two recording/reproducing rotary heads (heads A and B) placed 180 degrees opposite each other on a rotary cylinder; (4) is a two-track amplifier; (5) is an intra-frame signal processing circuit that adds an error correction code, interleaves, etc. to the recorded signal in units of one frame during recording, and performs error correction, de-interleave, etc. on the reproduced signal during playback. (5) is in units of one sector (6) is a cylinder servo circuit that drives and controls the rotating cylinder; (7) is an in-sector signal processing circuit that adds an error correction code, performs interleaving, etc. during recording, and performs error correction, de-interleaving, etc. during playback. (8) is a reel servo circuit that drives and controls the reel motor; (8) is a capstan servo circuit that drives and controls the capstan motor;
9) is an ATF circuit that extracts a signal in the ATF area from the playback output outputted from the recording/playback amplifier (3) via the intra-frame signal processing circuit (4) during playback and generates a tracking error signal. is supplied to the capstan servo circuit (8) and used to control the rotation of the capstan motor. (10) is a sub-food processing circuit that extracts signals in the sub-food area from the playback output outputted from the recording/playback amplifier (3) via the intra-frame signal processing circuit (4) during playback; The in-sector signal processing circuit (5), the in-frame signal processing circuit (4), the cylinder servo circuit (6), and the reel servo circuit ( 7) is a system control circuit that controls the capstan servo circuit (8).

(12) is an input/output device that serves as an input/output terminal to the host computer, and (13) is an input/output device that instructs the system control circuit (11) in response to commands from the host computer through this input/output device (12). The command circuit (12) is configured as shown in FIG. That is, (14) is a class memory in which the number of tape divisions that can be specified according to the tape harvest is stored in advance, and (15)
) is a sector memory in which the usage status of each sector in the data area of the currently accessed class is recorded, (16)
(17) is the TOC main memory where the TOC information recorded in the TOC area of the currently accessed class is temporarily stored; (17) is the main memory that temporarily stores the data sent from the host computer when recording a file, and from the tape when playing back. Data buffer memory for temporarily storing reproduced data (1B
) is an instruction decoding circuit that decodes instructions from the host computer and outputs them to the control circuit described later; (19>) is a class memory (14) that receives the output from the instruction decoding circuit (18);
Sector memory (15), To(, 'mo1j (16), data buffer memory (17), system control circuit 1 (11)
and a control circuit that controls a TOC sub-memory, which will be described later.

(20) stores the class number and the TOC information change history that is changed by erasing and recording files in the class, and is configured to retain the stored contents even when the power is turned off, such as a non-volatile memory. This is the TOC sub-memory.

Next, the operation of the data recording/reproducing method of the present invention is shown in FIGS. 6 and 7.
This will be explained with reference to the flowchart in the figure.

First, when the power is turned on in step (21), step (22) is executed to detect the presence or absence of a cassette. If the condition is normal, no cassette is installed when the power is turned on, and the device waits for the cassette to be installed in step (23). When the cassette is loaded, for example λ, the tape is played back from the beginning and class 1 TOC information is loaded into the TOC main memory (16) (step (24)), completing the initial settings. Thereafter, predetermined processing is performed according to instructions from the host computer with reference to the TOC information in the TOC main memory (16).
SW) is turned on, whether or not there is a change in the class number to be accessed, and whether or not there is a change in TOC information caused by erasing and recording files is constantly determined. That is, the change of the class accessed from the host computer in step <26) is
When fiM is performed, information in the TOC main memory (16) is written to the TOC area of the tape in step (28).
Step 29) searches the TOC area of the class number to be changed and loads the TOC information into the TOC main memory (16). Also, step (27) by erasing and recording files.
When it is determined that the TOC information should be changed, step (30)
In step (31), the change history of TOC information is written in the TOC secondary memory (20), and the TOC main memory (16) is changed based on the TOC secondary memory (2G). Now, let us consider the case where a file with a size of 0, for example, 3 sectors is recorded, as will be described with reference to FIG. File data is recorded on the tape in sectors n+1 and n+2, and as a result, TOC information is converted, so TO
n, n+1, n stored on C main memory (16)
The +2 sector hood is rewritten with new information, and the changed new sector code is stored in the TOC sub-memory (20). In this way, TOC secondary memory (20)
stores the modified sector hood according to the modification class. In this way, the latest TOC information is stored in the TOC main memory (16), and the sector food of only changed sectors is stored in the TOC secondary memory (20).

When the predetermined processing is completed and the EJECT SW is operated, the process proceeds from step (25) to step (32), and the TOC information stored in the TOC main memory (16) is transferred to the T of the tape.
After recording in the OC area, the cassette is ejected in step (33).

The above is a normal operation, but next we will explain the case where an abnormal situation occurs. As described above, in the present invention, before the cassette eject operation is performed, the TOC main memory (
16) Although the configuration is configured to record the latest TOC information above in the TOC area of the tape, if the power is cut off due to a power outage etc., the latest TOC information in the TOC main memory (16) will disappear. The occurrence of such an abnormal situation in which the TOC area of the tape cannot be rewritten is detected by the presence or absence of the cassette when the t source is turned on at the station (22), and the TOC sub-area consisting of non-volatile memory is detected. The TOC information is restored by the following operations based on the information remaining in the memory (20). That is, the TOC information of the class number stored in the TOC secondary memory (20) in step (34) is transferred from the tape to the TOC main memory (16).
In step (35), the TOC secondary memory (20
) based on the change history of TOC information stored in
The main memory (16) is changed, and then in step (36) the changed TOC information of the TOC main memory (16) is recorded in the TOC area of the tape, and the TOC information before the occurrence of the abnormality is recorded.
It is restored to C information.

In step (37), it is determined whether the restored TOC information is class 1 TOC information, and if it is not class 1, step (24) is executed to perform initial settings. Although not shown in the flowchart, when changing the class or ejecting a cassette, the TOC secondary memory (20
It goes without saying that the memory contents of ) will be erased.

Effects of the Invention According to the data recording and reproducing apparatus of the present invention described above, even if an unexpected situation such as a power outage occurs and the TOC information in the TOC main memory disappears, the TOC secondary memory can restore the TOC information. This can improve reliability. Furthermore, since the TOC sub-memory is configured to store the change history of TOC information, the memory capacity can be small and power consumption is also low.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention, in which Fig. 1 shows the division form of a 120-minute tape, Fig. 2 shows the track format, Fig. 3 shows the TOC area, and Fig. 4 shows the system. FIG. 5 is a diagram showing a specific configuration example of the command circuit, FIGS. 6 and 7 are flowcharts, and FIG. 8 is a diagram illustrating a case where TOC information is changed.

Claims (1)

[Claims] (1) A rotary head type tape recorder in which a data area and a table of contents area for recording table of contents information of files recorded in the data area are formed on a tape that is helically scanned by a rotary head, comprising: A first storage means for storing the table of contents information recorded in the table of contents area, and a second storage means for storing a change history of the table of contents information changed by writing and erasing files, the second storage means A data recording and reproducing system for a rotary head tape recorder, characterized in that the data is retained even when the power is turned off.