JP2749275B2 - Data recording / reproducing device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for recording a signal by a helical scan method. 2. Description of the Related Art A helical scan type magnetic tape storage device can obtain a higher recording density than a fixed head type magnetic tape device, so that it is widely used in fields requiring a large amount of information such as a VTR. Used. Further, with the development of VTR technology in recent years, home use VTRs have been produced in large quantities and at low cost, and are about to be widely used. Therefore, if the home VTR technology is used, a large-capacity and inexpensive magnetic storage device can be realized. However, a helical scan type VTR is
The recording track is determined by the relative position of the rotating head mounted on the cylinder and the magnetic tape running around the cylinder. Therefore, unlike a magnetic disk device, there is a major drawback that random access cannot be performed. For a computer storage device, data reliability is a very important factor. Therefore, in a magnetic disk device such as a flexible disk, when data is recorded, data to be recorded is first recorded on a magnetic disk, and then the data is reproduced to check whether the data is correctly recorded. If an error has occurred, recording is performed again. However, helical scan type VT
At R, since the magnetic tape is running at a constant speed as shown in FIG. 1, the magnetic head automatically moves to the next track, and the recorded data cannot be reproduced and checked. When the running of the magnetic tape is stopped, the recording head is deviated from the track because the recording track is determined by the relative position of the rotating magnetic head and the running magnetic tape, and the signal cannot be reproduced correctly. Therefore, in order to reproduce and confirm the data once recorded, it is necessary to rewind the magnetic tape and then run the tape again to reproduce the data. In order to re-record the recorded data, it is necessary to rewind the tape and restart the running. In general, rewinding the tape and restarting the run requires a very long time, and confirming and re-recording such data is not practical. [0007] As a device using a home VTR,
P to convert music signal to digital value and record on VTR
There is a CM recorder. The PCM recorder is exactly the same as a magnetic tape device in recording and reproducing digital values. The PCM recorder uses an error correction code in order to improve data reliability. But,
The error correction code can correct a minor error but cannot correct a severe error. In the case of an audio signal, even if a serious error occurs, for example, about once every 30 minutes, it cannot be said that the error is fatal. Therefore, only the error correction code is sufficient. No need. However, when used as an external storage device such as a personal computer, any small error can be fatal, and it is essential to check the recorded data. In a helical scan type magnetic tape storage device for recording a digital signal, confirmation of data recorded as described above and re-recording of data when a recording error occurs are performed. For this purpose, it is necessary to temporarily stop the running of the tape, rewind the tape, and then run the tape again at a predetermined speed. SUMMARY OF THE INVENTION It is an object of the present invention to provide a highly reliable magnetic tape data recording apparatus capable of recording data without error without interrupting normal tape running even when a recording error occurs during data recording. It is to provide. [0010] In order to achieve the above object, the present invention has the following configuration. That is, in a data recording / reproducing apparatus having a cylinder and recording data so as to form a helical track on a magnetic tape, an angle of about 180 degrees is formed on the cylinder with respect to a circumferential direction of the cylinder. So as to scan substantially the same track as viewed in a direction along the rotation axis of the cylinder, and are arranged to be shifted from each other by a predetermined distance, and the predetermined distance is always constant. A recording head and a reproducing head fixedly attached to the cylinder, encoding means for converting data to be recorded into a recording waveform and supplying the recording head with the recording head, and a reproducing waveform of a signal reproduced by the reproducing head. Decoding means for reproducing recorded data, and recording abnormalities for detecting whether data was recorded normally Output means, tape drive means for continuously running the tape at substantially the same speed during data recording and data reproduction, and when recording data abnormality is detected by the recording abnormality detection means during data recording. Comprises a data re-recording means for re-recording the data in which the abnormality has been detected at a position on the magnetic tape different from the track in which the abnormality has been detected. It is configured to be used only for recording without being used. Further, the data re-recording means is configured to record a signal indicating that the abnormality has been detected, together with re-recording of the data in which the abnormality has been detected. According to the head arrangement on the cylinder of the present invention, a simple arrangement is provided.
Low cost in a single structure, de - when data recording tape - whether it is possible to easily find an abnormality in data, further data of the present invention - - recorded de that while it is traveling up data recording instrumentation When an abnormality occurs in the device, data is rewritten together with a signal indicating the abnormality. 2 and 3 show a recording format and a block diagram of a reference example , which will be described below with reference to the drawings. Data recording is performed by the first and second recording heads 5 and 7, and data reproduction is performed by the first and second recording heads.
With the reproducing heads 6, 8. The first and second recording heads 5, 7 are installed on a diagonal line on a cylinder (not shown), and the first and second reproducing heads 6, 8 are also provided on a diagonal line on the cylinder. I have. The two recording heads 5, 7 alternately scan the recording tracks, and the two reproducing heads 6, 8 also alternately scan the tracks. When recording data, the bus line 1
1 is sent to a memory 17 and an encoding circuit 13 through a control circuit 12 for performing an interface operation with the CPU and the like, and a recording signal converted by the encoding circuit 13 is recorded by a recording amplifier 14 and a recording head 5.
(Or 7) to record on the magnetic tape. At this time, the reproducing head 6 (or 8) which scans the same track with a slight delay reproduces the signal just recorded,
The data is converted into reproduction data by a reproduction amplifier 15 and a decoding circuit 16. The coincidence detecting circuit 18 compares the recorded data stored in the memory 17 with the reproduced signal output from the decoding circuit for all the tracks. When the recorded data and the reproduced data all match, the data valid signal X is sent to the encoder circuit 13, the recording amplifier 14,
Using the recording head 7 (or 5), recording is performed at the beginning of the next track, and subsequently, data to be recorded next is requested from the CPU side (not shown) and recorded. If the recorded data does not match the reproduced data, the data invalid signal Y is recorded, and the recorded data stored in the memory 17 is recorded again. Therefore, data is recorded on the track on the magnetic tape as shown in FIG. When data a is recorded on track 1 and correctly reproduced by the reproducing head, a data valid signal X is recorded at the beginning of track 2. The next data b is continuously recorded on the track 2. However, although the data c is recorded on the track 3, the reproduced signal is c 'for some reason such as a scratch on the magnetic tape. Therefore, the data invalid signal Y is recorded at the beginning of the track 4, and the data c is recorded again on the track 4. When reproducing data, the data is reproduced using the reproducing heads 6 and 8. In this case, if there is a data invalid signal Y, the data before that track is discarded. That is, when the data invalid signal Y is reproduced by reproducing the track 4, the data c 'reproduced in the track 3 is discarded and the data c of the track 4 is used. In the reference example of FIG. 3, the data valid signal X or the data invalid signal Y is recorded at the head of the next track by the recording head 5 or 7, but the reproduction amplifier 15
And the recording amplifier 14 are temporarily switched so that the reproducing head 6
Alternatively, it is also possible to record at the end of the track by using 8. The tracks on the magnetic tape in this case are as shown in FIG. In the reference example shown in FIG. 3, two heads are used for the recording head and two heads for the reproducing head. However, the same can be achieved by using two heads installed on a diagonal line of the cylinder. In this case, it is necessary to shift the installation position of one head as compared with the other head, and to make adjustments so that two heads scan the same track. This will be further described with reference to the drawings. FIG. 7 shows an embodiment of the present invention in which one recording head and one reproducing head are used in the reference example of FIG. The recording head 5 and the reproducing head 6 are mounted on a diagonal line of the cylinder (a position opposed to each other by 180 degrees), and as shown in FIG. Adjusted and installed. In the reference example of FIG. 3, the track recorded by the recording head 5 is reproduced by the reproducing head 6,
Next, the operation of reproducing the track recorded by the recording head 7 by the reproducing head 8 is repeated.
In the embodiment of the present invention, the reproduction head 6 reproduces the track recorded by the recording head 5 repeatedly. Except for the operation, the recording / reproducing apparatus performs the same operation as the apparatus of the reference example in FIG. As described above, according to the present invention, when data is recorded, even if a recording abnormality occurs, a normal data can be recorded.
Without interrupting the tape running, de errorless - data recording capable reliable magnetic tape - de of flop - easy to data recording and reproducing apparatus
It can be provided at a low cost with a simple configuration .

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram showing an example of a recording format of a helical scan type magnetic tape storage device. FIG. 2 is an explanatory diagram showing a data recording / reproducing configuration according to a reference example . FIG. 3 shows a magnetic tape data recording / reproducing apparatus according to a reference example .
Configuration diagram showing a configuration of a. FIG. 4 is an explanatory diagram showing recording tracks according to a reference example . FIG. 5 is an explanatory view showing another record track by the reference example. FIG. 6 is an explanatory diagram showing a data recording / reproducing configuration according to the embodiment of the present invention. FIG. 7 is a block diagram of a data recording / reproducing apparatus according to an embodiment of the present invention.
Diagram showing the formation. [Description of Signs] 1 ... magnetic tape, 2 ... video track, 3 ... audio track, 4 ... control track, 5 ... first recording head, 6 ... first reproducing head, 7 ... second recording head, 8
... Second reproducing head, 11 bus line, 12 control circuit, 13 encoding circuit, 14 recording amplifier, 15
Regeneration amplifier, 16: decoding circuit, 17: memory, 18
... Match detection circuit.

Claims (1)

(57) [Claims] In a data recording / reproducing apparatus having a cylinder and recording data so as to form a track in a helical shape on a magnetic tape, the data recording / reproducing apparatus may be arranged on the cylinder in a circumferential direction of the cylinder
They are arranged so that they face each other at an angle of about 180 degrees
And a predetermined distance from each other so as to scan substantially the same track as viewed in a direction along the rotation axis of the cylinder.
And the predetermined distance is always constant
Each said cylinder attached to the fixed shape as
A recording head and a reproducing head, encoding means for converting data to be recorded into a recording waveform and supplying the recording waveform to the recording head, and decoding means for reproducing data recorded from a reproduction waveform of a signal reproduced by the reproduction head. a recording abnormality detecting means for detecting whether data has been recorded successfully, in approximately equal speed during the data recording and reproduction, and communication
A tape driving means for connection to running the tape, at the time of data recording, the recording data by the recording abnormality detecting means
If the abnormality of the motor is detected, the position on different magnetic tapes is an abnormality has been detected a track, abnormality is detected
A data re-recording means re-record data, and includes a
The recording head is not used for reproducing data.
A data recording / reproducing device characterized by being used exclusively for recording. 2 . 2. The data recording / reproducing apparatus according to claim 1, wherein the data re-recording unit records a signal indicating that the abnormality has been detected, together with re-recording of the data in which the abnormality has been detected.