JPH0828056B2 - Data recorder - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data recorder for recording data from a computer or the like using a rotary head type digital audio tape recorder (DAT).

[Outline of Invention]

The present invention relates to a decoder recorder, in which a so-called DAT recording device is diverted, a data invalid flag area is provided in a signal, and when there is no external data, this flag is set to perform recording so that good recording can always be performed. It is something to do.

[Conventional technology]

For example, in a computer, in order to protect data written in a hard disk or the like, such data may be transferred to a so-called data streamer (recorder) once a day and recorded (backed up) in another recording medium. It is being appreciated.

In that case, as the above-mentioned data streamer, a so-called analog audio tape recorder has been conventionally used in many cases. However, in such an analog tape recorder, the consumption of the recording medium becomes extremely large,
In addition, since the data rate at the time of recording is low, it takes an extremely long time to transfer and record. Further, there is a problem that it is not possible to easily find the desired recording portion.

By the way, a so-called DAT (Digital Audio Tape Recorder) is being developed ("ES Review" Sony Corporation Shibaura Plant Issue: ISSN 03
89-7737: December 1985, pp. 11-17, etc.).

According to the DAT, since it is originally designed to record and reproduce digital signals, it is suitable for data recording as described above. However, in the case of such a DAT, since a rotary head is used, it takes a relatively long time to start recording / reproducing. Therefore, for example, when recording is interrupted, once recording is stopped, data is re-recorded. There is a possibility that recording may not be performed smoothly due to a delay in the start-up when the time comes.

[Problems to be solved by the invention]

As described above, the conventional technique has problems that the consumption of the recording medium is increased and the recording takes a lot of time because the analog recording data streamer is used.

[Means for solving problems]

The present invention has a rotating head, and two rotation tracks are formed by one rotation of the rotation head, and the digital signal is completed within one frame by using the two tilt tracks as one frame. Data recorder (DAT)
In (1)), a flag area (subcode) indicating invalidity of data is provided in at least a part of the signal forming one frame, and when there is no data to be recorded,
It is a data recorder provided with means for recording a flag indicating invalidity of data.

[Action]

According to this, an invalid flag area for data is provided for each frame of DAT, and when the recording data is interrupted, the invalid flag is set and recording is performed, and when the data arrives again, this is immediately recorded. As a result, the DAT can be smoothly used as a data streamer, whereby a good data recorder that consumes less recording medium and less time is required for recording can be obtained.

〔Example〕

In FIG. 1, (1) shows the structure of the DAT.
(1) is provided with a rotary head drum (11), and the magnetic tape (12) is wound around and transported by a range of about 90 degrees around the drum (11). And this drum (11)
Two heads A and B are provided on the upper side, and two inclined tracks are recorded and reproduced by one rotation of the drum (11).

On the other hand, digital data from the outside is input to the IO circuit (13), and is supplied from the IO circuit (13) to the digital signal processing circuit (14) to be converted into the DAT format described above. The formatted signal is supplied to the heads A and B through the recording amplifier (15) and the recording / reproducing switch (16) on the recording side, and is recorded on the tape (12).

When the signal recorded on the tape (12) is reproduced by the heads A and B, the reproduced signal is recorded / reproduced by the switch (1
The digital data, which is supplied to the processing circuit (14) through the reproduction side contact of 6) and the reproduction amplifier (17) and is inversely converted and taken out, is output to the outside through the IO circuit (13).

Further, an external control signal is supplied to the system control circuit (18), and the signal from the control circuit (18) controls the rotation of the head drum (11), the transfer control of the tape (12), and the switch (16) switching. In addition to being controlled, the recording control circuit (18)
Is supplied to the processing circuit (14) to form a subcode signal which will be described later. During reproduction, the signal extracted by the processing circuit (14) is supplied to the control circuit (18) to control tracking and the like, and at the same time a part of this signal is taken out.

DAT (1) is formed by the above configuration. In this device, a DA / AD conversion circuit is provided outside the IO circuit (13), and a predetermined control device is provided outside the control circuit (18), so that, for example, recording / reproducing of an audio (analog) signal is performed. be able to.

On the other hand, in the above-mentioned device, an arbitrary interface bus (3) is connected to the outside of the DAT (1) via the controller (2). Here, as the interface bus (3), for example, the SCSI standard (“NIKKEI ELECTROMIC
S ", published by Nihon Keizai Shimbun: October 6, 1986, pp. 102-107). Furthermore, this bus (3)
A host computer (5), a hard disk device (6) and the like are connected to the host computer via an adapter (4).

A protocol control circuit (21) is provided between the controller (2) and the bus (3), and the microcomputer (22) controls the operation of the controller (2) via the control circuit (21). ) And a memory control (DMA) circuit (23), and data and control signals are exchanged between the bus (3). Further, state detection and operation control are performed between the microcomputer (22) and the DMA circuit (23), and data is transferred between the buffer memory (24) and the bus (3) through the DMA circuit (23). Input and output are performed. The IO circuit (2) is connected between the memory (24) and the processing circuit (14) of the DAT (1).
5) Data input / output is performed via (13). In addition, control signals are exchanged between the microcomputer (22) and the system control circuit (18).

Therefore, in this device, the hard disk device (6)
The data written in is recorded in the controller (2)
In response to a transfer request from the memory, the data is input to the controller (2) through the bus (3), and the memory (2
Written in 4). Further, the data written in the memory (24) is read out via the IO circuit (25) and input to the DAT (1). Then, in this DAT (1), the IO circuit (1
The data input to 3) is regarded as the same as the data from the AD conversion circuit during voice recording, and the digital signal processing circuit (1
4) converted to the specified DAT format in head A,
Recorded on tape (12) at B.

At the time of reproduction, the signals reproduced by the heads A and B from the tape (12) are inversely converted by the digital signal processing circuit (14) to extract the data corresponding to the audio signal. Furthermore, this data is sent to the controller (2) via the IO circuit (13).
Is input to Then, in this controller (2), the data written in the memory (24) through the IO circuit (25) is read out through the DMA circuit (23) and written in the hard disk device (6) through the bus (3). Get caught.

Furthermore, in this device, it records on the tape (12)
The DAT format is as follows.

In FIG. 2, one frame is composed of two tracks Ta and Tb recorded by heads A and B, and these tracks are formed from the lower side of the drawing, and this recorded signal has a full length. 5.051 degree margin from 90 degrees to 90 degrees → Preamble part for PLL of 0.918 degree subcode → First subcode section of 3.673 degree → Post ampule section of 0.459 section → Gap between blocks of 1.378 section Division → 2.296
Degree tracking (ATF) signal section → 1.378 degree inter-block gap section → 0.918 degree data preamble section for PLL → 58.776 degree data section → 1.378 degree inter-block gap section → 2.296 degree ATF signal section → 1.378 Inter-block gap section → 0.918 degree subcode PLL preamble section →
The second subcode portion is 3.673 degrees, the postamble portion is 0.459 degrees, and the margin portion is 5.051 degrees. The scale of the figure is not accurate. Then, in the above device, the data input from the IO circuit (13) is added with a predetermined error detection / correction code or the like in the processing circuit (14), and the data portions of the tracks Ta and Tb are interleaved in a predetermined interleaved relationship. It is distributed and inserted.

Further, in the above-mentioned device, 2048-bit data can be recorded in each of the first subcode part and the second subcode part. In the audio signal recording format, divide this 2048 bit into 64-bit packs,
Information such as the time code of the signal recorded for each pack and the recording date and time is recorded.

Therefore, a pack for a data recorder can be assigned to this pack so that various controls can be performed using this pack.

That is, FIG. 3 shows the structure of a pack for that purpose. In the figure, 64 bits are divided into 8 words of 8 bits each. The 4 bits on the MSB side of the first (first) word in this pack are the ITEM area, and this area is common to the audio signal recording format, and the contents of the pack are displayed in this 4-bit binary code. It It should be noted that 9 out of 16 codes of 4 bits are already defined for recording audio signals, etc., and any of the remaining 7 codes is defined for the data recorder.

Further, the 3 bits on the LSB side of the first word and the next 2nd word are used as a save set number (SSNO) area, and a binary value indicating the number of backups from the leading end of the tape is provided by a total of 11 bits. .

The third word is a file number (FNO) area, and a binary value indicating the serial number of the file in the data (save set) backed up at one time is provided.

Further, the 4 bits on the LSB side of the 4th word and the 5th and 6th words are used as an absolute frame number (AFNO) area, and a binary value indicating a serial number of a valid frame from the leading end of the tape is provided by these 20 bits. Can be

The seventh word is used as a status display area. In this word, the first bit on the MSB side is the flag area indicating that the frame is the backup end position (readout), and the second bit is the flag area indicating that the data of that frame is invalid. , Third
The bit is a flag area indicating that the frame is a frame in the amble period at the beginning and end of recording, and the fourth bit is a flag area indicating that the frame is a file mark. Further, a numerical value representing the number of blocks recorded in one frame as a binary value is provided in 4 bits on the LSB side as a data amount in one frame, for example, a unit data amount of input / output with the outside as a block. Note that the 5th bit from the MSB side of the 1st word is "0", the 4 bits on the MSB side of the 4th word are all "0" for the time being as extension bits, and the 8th word is the 1st to 1st It is the parity for 7 words.

So, in the above-mentioned device, for example, when backing up data from the hard disk device (6),
The write address and the read address of the DMA circuit (23) are compared, and when the buffer memory (24) becomes empty due to data interruption or the like and the addresses match, the signal is supplied to the microcomputer (22). Then, this signal is supplied to the digital signal processing circuit (14) through the system control circuit (18), and a data invalid flag "1" is set in the second bit of the seventh word of the data recorder pack of the subcode section. At the same time, arbitrary invalid data is inserted in the data section for recording.

Therefore, in this apparatus, since recording is continued even if data is interrupted, there is no inconvenience due to a delay in rising at the time of resuming recording, which is caused by stopping recording, and it is possible to always perform smooth recording.

Thus, according to the above device, DAT can be used as a data streamer, and in this case, according to the above configuration, since the rotary head drum (11) is rotated at 2000 rpm, for example, data recording is 192,000 bytes per second. It can be performed at extremely high speed and consumes very little recording medium. Further, in this case, according to the above configuration, the data from the outside can be smoothly recorded even if a break or the like occurs, so that excellent data recording / reproduction can be performed.

According to the above configuration, since the recording density is extremely high, there is no problem even if the above invalid data is recorded. However, in that case, the DAT may be stopped when the invalid period continues for one second or more.

In addition, by not increasing the absolute frame number (AFNO) provided in the fourth to sixth words in the data recorder pack during the invalid period, it is possible to eliminate the influence on the data search operation.

〔The invention's effect〕

According to the present invention, an invalid flag area for data is provided for each frame of DAT, and when the recording data is interrupted, the invalid flag is set and recording is performed, so that when the data arrives again, the invalid flag area is immediately set. Since data can be recorded, this DAT can be smoothly used as a data streamer, and thereby a good data recorder that consumes less recording medium and requires less time for recording can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram of an example of the present invention, and FIGS. 2 and 3 are diagrams for explaining the same. (1) is DAT, (2) is controller, (3) is bus,
(4) is an adapter, (5) is a host computer,
(6) is a hard disk device.

Claims (1)

[Claims] 1. A rotary head is provided, and two tilted tracks are formed by one rotation of the rotary head, and these two tilted tracks are regarded as one frame, and a digital signal is completed within this one frame. In a data recorder that is encoded and recorded / reproduced as described above, a flag area indicating invalidity of data is provided in at least a part of the signal forming one frame, and when there is no above-mentioned data to be recorded, data is recorded. A data recorder equipped with a means for recording a flag indicating that the data is invalid.