JPH03137873A - Digital data recording/reproducing device - Google Patents

Abstract

PURPOSE:To prevent a recording data from missing and lacking even in the case of a burst error and to reproduce the data at the real time by recording the occurrence of an error in an incidental data area when the error takes place at the time of recording. CONSTITUTION:At the time of recording, an input data Di is inputted to a signal processing part 7, and after processing an addition of an error correction data, etc., recording is performed in turn on a tape 2. Subsequently, it is reproduced by a reproducing head 5, and the presence of a burst error is detected by an error detecting circuit 8, and then the contents of a recording data, in which a recording error occurs, are stored by the processing part 7 in a memory 9 at a prescribed address, is recorded into subcode area at the succeeding write timing. At the time of reproducing, when a burst error is detected by the processing part 7 during reproducing data, the burst error data stored in the memory 9 is outputted via a change-over switch 11 for responsing to a changeover signal SW to a line L9. By this method, the recording data is prevented from missing and lacking, and the data can be reproduced at the real time.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a digital data recording/reproducing device suitably implemented in a DAT (digital audio recorder) or the like.

2. Description of the Related Art Digital data recording/reproducing apparatuses, such as DAT, which record digital data on a tape-shaped magnetic recording medium or reproduce digital data recorded on the tape, include an error correction code in the data at the time of recording. There are methods that perform signal processing such as addition and interleaving of data and perform error correction during reproduction, and methods that rewrite the data after detecting an error in the recorded data.

Problems to be Solved by the Invention However, in the former method, which performs signal processing such as adding an error correction code and interleaving data, and performs error correction based on the above data during reproduction, data bit errors, block errors, etc. Although this method is suitable for so-called random errors, it is not suitable for so-called burst errors in which errors occur continuously.

On the other hand, the latter method, which rewrites the data after detecting an error in the recorded data, does not require real-time processing of data, as is the case with external storage devices for combi-users such as data recorders. However, it is not suitable for data that must be processed in real time.

Therefore, it has been a technical challenge to realize a digital data recording/reproducing device that can solve these problems, deal with burst errors, and perform data processing in real time.

The present invention has been made in view of the above-mentioned problems, and includes:
It is an object of the present invention to provide a digital data recording/reproducing device capable of dealing with burst errors and executing data processing in real time.

Means for Solving the Problems The present invention is a digital data recording/reproducing device that records input digital data on a recording medium and reproduces and outputs the recorded data, which adds accompanying data to the input data. processing means for converting the data into a data format of recorded data and converting the reproduced data into a data format of output data; an error detection means for detecting a data recording error; and a delay means for delaying the reproduced data by a predetermined time, and the processing means responds to the output of the error detection means to delay the data in which the recording error has occurred by a predetermined time from the data. Digital data recording is characterized in that the data is read out from the storage means at a later time and recorded in an accompanying data area of the data to be recorded at that time! /It is a playback device.

Function: The digital data recording/reproducing device according to the present invention includes an error detection means for detecting recording errors such as burst errors, and a storage means for storing data at the time of error detection.
When a recording error is detected during input data recording, the processing means causes the storage means to store the data resulting in the error. When a predetermined time has elapsed since the error detection time, the processing means reads out the stored data from the storage means and records it in the accompanying data area of the data to be recorded at that time.

When reproducing data, data is sequentially read from the recording medium and reproduced after being delayed by the predetermined time by the delay means. When the reproduction operation reaches the error position, the processing means reads out the data in the missing data area without delay, compensates for a portion of the error, and outputs the data.

Embodiment FIG. 1 is a block diagram showing the electrical configuration of a digital data recording/reproducing apparatus 1 according to an embodiment of the present invention.

Digital data recording/reproducing device (hereinafter referred to as the device)1
is a recording medium, magnetic tape (hereinafter referred to as tape).
A recording magnetic head (hereinafter referred to as recording head) 3 which is a recording means for writing and recording input data on tape 2 and a recording amplifier 4, and a reproduction device for reading and reproducing data recorded on tape 2. It is provided with a reproducing magnetic head (hereinafter referred to as a reproducing head) 5 and a reproducing amplifier 6, which are means.

Here, the tape 2 is moved by an arrow A by a drive unit (not shown).
The recording head 3 and the reproducing head 5 are arranged adjacent to each other so that the recorded contents can be read and reproduced by the downstream reproducing head 5 immediately after recording by the upstream recording head 3. . Hereinafter, in order to distinguish between data recorded on the tape 2 and data reproduced from the tape 2, a lowercase letter W will be added to the reference numeral representing the data, and a lowercase letter r will be added to the latter.

The device 1 also includes a signal processing unit 7 formed mainly of a microprocessor (not shown), a memory unit that is a storage means for writing and storing data in a predetermined area, and a system that detects the presence or absence of burst errors in the reproduced signal Dr. Error detection circuit 8, data delay circuit 10, and output selector switch 1
1.

Next, the operation of the device 1 will be explained with reference to FIG. During recording, the input data Di applied to the input terminal 12 is
Line r2 is input to the signal processing unit 7 via line 11, and is subjected to signal processing in accordance with a predetermined format for recording digital data, including the addition of accompanying data such as error correction data. is applied to the recording head 3 via the recording amplifier 4, and tracks of recording data Dw are sequentially formed on the tape 2.

The recorded data Dw recorded on the tape 2 is reproduced on the recording surface 1 by the downstream reproducing head 5, and the reproduced data Dr is input to the reproducing amplifier 6. The reproducing amplifier 6 amplifies the reproduced data Dr, performs processing such as waveform shaping, and then inputs the data to the signal processing section 7 and the error detection circuit 8 via the line 13.

The error detection circuit 8 detects the presence or absence of a burst error when recording the reproduction data output from the reproduction amplifier 6, and when a burst error is detected, for example, a high level r is detected.
The error detection signal Se of H, is input to the signal processing section 7 via the line 14.

The 20th is a waveform diagram showing the operation during data recording of this embodiment. Reference numbers correspond to FIG.

Fig. 2 (1) to Fig. 2 (3) show the regeneration team 9 Dr.
shows the waveforms of each part when it is normal and no burst error occurs.

In this case, as shown in FIG. 2(1), the recording data DWODw1, Dw2 . Dw3.・
... (indicated by the reference mark Dw when collectively referred to) are sequentially recorded in the main code area A1 at the center of the track on tape 2.
recorded in

In addition, on both sides of the main code area A1,
Subcode areas A2 and A3, which are accompanying data areas, are formed.

The recorded data Dw is immediately converted into reproduced data DrO, Drl Dr2, Dr3 . . . by the downstream reproducing head 5 shown in FIG. ...
(When collectively referred to as the reference mark Dr), the data is sequentially reproduced.As is clear from these FIGS. 2(1) and 2(2), the recorded data DWO is the reproduced data DrO.
, data Dwl corresponds to data Drl, and so on.

In this way, when the reproduced data Dr is normal and no burst error occurs, the output of the error detection circuit E@8 is constant at the low level "L" as shown in FIG. 2 (3).
The error detection signal Se is not output.

On the other hand, as shown in FIG. 2 (4) and FIG. 2 (5), when a recording error occurs in the recording data Dwl due to a burst error, the error detection circuit 8 As shown in FIG. 6, an error detection signal Se of high level "H" is derived to the line 14.

When the error detection signal Se is input from the line 14, the signal processing unit 7 processes the recorded data D w in which a recording error has occurred.
1 is input to the memory 9 via line 15 as burst error data Dm as shown in FIG. 2 (7), and is written and stored at a predetermined address.

The data Dml stored in this way is stored in the subcode area A2. Recorded on A3. While repeating such operations Ii, recording and reproduction on the tape 2 proceed simultaneously.

Referring to FIG. 1, during playback, the output of the signal processing section 7 is as follows:
It is input to the data delay circuit 1° via line 18.

The data delay circuit 1o outputs the reproduced data Dr after being delayed for a predetermined period of time, and the delayed data Drb is outputted to one individual contact of the changeover switch 11. The other individual contact a of the changeover switch 11 has a memory 9
Burst error data Drm is read out from the signal processing section 7 and output via line 17.

The changeover switch 11 connects the signal processing section 7 to the line I! In response to the switching signal Sw derived via the output line I! The contacts a and b are connected by switching the contacts a and b, and during normal playback, the contacts b and c are electrically connected, and when a burst error is detected in the playback data Dr, the switching signal Sw is used to connect the contacts b and c. -c becomes conductive, and the burst error data Drm stored in the memory 9 is output to one output line.

FIG. 3 is a waveform diagram showing the operation during reproduction of this embodiment. FIGS. 3(1) to 3(5) show waveforms of the P4 session in which the reproduced data Dr is normal.

Referring also to FIG. 1, if there is no recording error in the reproduced data Dr, the reproduced data Dr shown in No. 3I21(1) is sequentially reproduced at fixed timing T, and the output is delayed by the data delay. The circuit 10 delays the reproduced original signal by a predetermined time 2T, as shown in FIG.
The delay data Drb shown in 2) is derived to the individual contacts of the changeover switch 11.

During this period, no burst error is detected in the reproduced data Dr, and the level of the error detection signal Se is low level "L".
'', and as shown in FIG. 3 (5), the changeover switch 11 is electrically connected to the individual contacts. Therefore, the delayed data Dr'b is output from the output line β9 to the output terminal 13 as reproduced output data DO, as shown in FIG. 3(4). Furthermore, the burst error data Drm from the signal processing circuit 7 is not derived as shown in 3) in FIG.

On the other hand, waveforms when there is a recording error in the reproduced data Dr are shown in FIG. 3 (6) and below. Here, it is assumed that the reproduced data DrO is lost during recording, and the data of that portion is stored as burst error data Drmo in the memory 9 as described above.

The omission of the reproduced data DrO shown in FIG. 3(6) is detected by the error detection circuit 8, and the error detection signal Se is immediately output. When the error detection signal Se is input, the signal processing unit 7 switches the changeover switch 11 to the individual contact a when the predetermined time 2T has elapsed, as shown in the third I2I<10).

As a result, the signal processing circuit 7 outputs the reproduced data Dr.
2 subcode area A2. The burst error data DrmO recorded in A3 is output to line 17 as shown in FIG. 3 (8).

Therefore, the delay data Dr shown in FIG.
As shown in FIG. 3(9), the burst error data [)rmo compensates for the reproduced data DrO portion, which is a portion of the recording error. In this way, even if a burst error occurs, the reproduced data Dr is not lost and is reproduced in real time.

In the above-described embodiment, the data delay time of the data delay circuit 10 was set to 2T, but this corresponds to the time from the occurrence of a burst error to the re-recording of data, and therefore the time until this re-recording varies. When the delay time is changed, the delay time is also changed accordingly.

Effects of the Invention As described above, even if a burst error occurs during recording, the digital data recording/reproducing device according to the present invention stores the recorded data at the relevant position in the memory and further records it in the accompanying data area. Therefore, recorded data is not lost and data can be played back in real time without any data being dropped during playback.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the electrical configuration of a digital data recording/reproducing apparatus 1 according to an embodiment of the present invention, FIG. 2 is a waveform diagram showing the operation during data recording of this embodiment, and FIG. FIG. 6 is a waveform diagram showing the operation during data reproduction in the embodiment.

Claims (1)

[Claims] In a digital data recording/reproducing device that records input digital data on a recording medium and reproduces and outputs the recorded data, the data format of the recorded data is determined by adding accompanying data to the input data. processing means for converting the reproduced data into a data format of output data; an error detection means for detecting a data recording error; and a storage means for storing data resulting in a recording error when the recording error occurs. , delay means for delaying the reproduced data by a predetermined time, and the processing means responds to the output of the error detection means to store the data in which the recording error occurred after the data by a predetermined time. A digital data recording/reproducing apparatus characterized in that the digital data recording/reproducing apparatus reads data from the source and records the data in an accompanying data area of data to be recorded at that time.