KR100283144B1 - Digital recording / playback device - Google Patents

Abstract

The present invention relates to a digital recording / reproducing apparatus, and according to the related art, when the recording occurs only once on the tape, if the tape is damaged by scratching or the like, it cannot be restored again during playback; When the recording tape is low grade, there is a problem that the reliability of the data is lowered.

Accordingly, the present invention has been made in order to solve the above-mentioned conventional problems, an amplifier / equalizer for amplifying and shaping an input signal and outputting it in synchronization with a head switching signal; Mode selection means for outputting a selection signal corresponding to the user's mode selection; A mode signal generator for generating a mode signal in accordance with a selection signal input from the mode selection means; Restoring means for restoring and outputting an input analog signal or a digital signal into a digital signal or an analog signal, respectively; A detection recording unit which detects the synchronization signal and the identifier signal from the digital signal input according to the mode signal generated by the mode signal generator, or attaches and outputs the synchronization signal and the identifier signal; According to the mode signal generated by the mode signal generator, the signal is converted into a predetermined format or restored to the same format as the signal input at the time of recording. A formatter to make; A final output selector for selecting error-free data according to a discrimination signal inputted from the formatter and the mode signal generator and a mode signal and a head switching signal and outputting a selection signal corresponding thereto; Reliability of data by providing a device composed of switching means for selecting and outputting data inputted in accordance with a mode signal inputted from the mode signal generator so as to have a function of overwriting by a user's selection or a type of tape to be inserted. In addition, it is possible to effectively cope with various tape grades, to cope with a harsh environment, and to use it for information storage, and to be applied as an additional function without changing existing specifications.

Description

Digital recording / playback device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital recording / reproducing apparatus, and more particularly to a digital recording / reproducing apparatus having a repetitive recording function in order to improve the reliability of data.

Conventional digital recording / reproducing apparatus uses an Error Correction Code (ECC) to guarantee the level of error rate necessary to record and play data. Referring to the two-dimensional error correction code (ECC), as shown in Figure 1 Synchronous (hereinafter referred to as "Sync") block is largely sync (Sync), identifier (ID), data and It consists of a parity part, and the size of the sync block, the inner parity and the inner parity can be variously adjusted in consideration of conditions such as reliability of the recording / reproducing system, safety and efficiency of data. . In other words, the degree to which the safety of the data is maintained is determined by the characteristics of the recording / reproducing system and the configuration of the error correction code given in particular, and this value can be expressed by the normal byte error rate (BER). The byte error rate (BER) of the system is usually a value of about 10e-2 to 10e-6, and when this value passes an error correction code, it is about 10e-10 to 10e-20. This value is fixed when the format is determined. It is fixed against changes in the situation such as the type of tape, the importance of data, the degradation of the tape, and the deterioration of the surrounding environment. In addition, it cannot maintain a normal hard disk level (BER: 10e-40 or less). In addition, as shown in FIG. 2, the track of the digital recording / reproducing apparatus has a margin (M), a preamble (PER-A), a sub-code (SUB), and a postamble (Postamble). POS-A), IBG (Inter Block Gab: IBG), main data, and the like, and the main data includes a sync, an identifier, and data.

FIG. 3 is a diagram illustrating a structure of a drum and a head of a 2-channel V-Cal for recording conventional high-definition data. As shown therein, heads H1 and H2 of different azimuths are attached in pairs. Another head H3, H4 is located at a position of 180 °, where the heads H1, H3 have the same orientation, and the heads H2, H4 have the same azimuth angle. The heads H1 and H2 perform the same operation at the same time, and the heads H3 and H4 also operate at the same time. Therefore, the number of tracks that can be formed per drum revolution is four tracks. In addition, as shown in FIG. 5, another head H3, H4 is positioned in a direction opposite to 180 ° of the heads H1, H2 attached in pairs, so that the number of tracks that can be formed per rotation of the drum is 6 tracks (4 recording tracks). And two dummy tracks).

In the case of recording with the head arrangement as shown in FIG. 3, as shown in FIG. 4, 4 tracks per revolution in the case of HD recording and 2 tracks per revolution in the case of SD recording can be formed. In the case of recording with the head arrangement as shown in FIG. 5, two tracks as described above can be formed in the case of SD recording, as shown in FIG. 6, but in the case of HD recording, six tracks per rotation, between two recording tracks Each dummy track in which no contents are recorded is formed.

In addition, since the heads H1 and H3 (H2 and H4) do not output signals at the same time, they can be processed by one signal processing circuit, which is called a channel, and the speed of the tape St is the width of the head and the drum. Speed, etc.

4 tracks per revolution, 2 tracks per revolution, 2 tracks per two revolutions, depending on the input data rate when recording HD signals in two channels. , recording / playback is possible with various track amounts such as 2 tracks per n revolutions.

As described above, in the case of reducing the recording rate in half in the four-track recording / reproduction method using two channels as described above, the tracks recorded per drum rotation as shown in FIGS. 4 and 6 in order to reduce the amount of data recorded in half or less. The number of must be reduced to half (2 tracks per revolution).

FIG. 7 is a block diagram showing the configuration of a conventional two-channel recording / reproducing apparatus, and FIG. 8 is a timing diagram showing an operation state of each reproducing mode according to the output of a head by rotation of a conventional drum. In operation mode in the HD playback mode, the head output by the rotation of the drum outputs the signals at the same time in each head (H1, H2, H3, H4) pair as shown in Figure 8a, the head switching signal (H / SW) is a signal representing the head phase on the drum, and the heads H1 and H2 operate at high and H3 and H4 operate at low to output an output. The output signals of the heads H1 and H3 are amplified and shaped by the first amplifier / equalizer 100 and then output in synchronization with the head switching signal H / SW, and the output signals of the heads H2 and H4 are second amplifiers. After being amplified and shaped in the / equalizer 110, it is output in synchronization with the head switching signal H / SW. The first and second restoring means 120 and 130 which receive the output signals of the first and second amplifiers / equalizers 100 and 110 are respectively restored to digital data and output the digital data. 140 and 150 detect the synchronization or identifier signal and are synchronized with the head switching signal (H / SW) to be transmitted to the first and second formatters 160 and 170 and the first and second formatters 160. ) 170 temporarily stores the data in the storage means (not shown), restores the same format as the signal input at the time of recording, and outputs the same to the selection means 180 in synchronization with the head switching signal H / SW. The selecting means 180 outputs data of two channels input to the outside through the interface means 190 by a control signal CS of a controller (not shown).

Referring to the operation state in the standard definition (hereinafter referred to as "SD") regeneration mode, the output of the head due to the rotation of the drum is such that the head switching signal (H / SW) is high as shown in FIG. At this time, the heads H1 and H2 operate to output an output. In this case, the heads H3 and H4 do not operate. The output signals of the heads H1 and H2 are amplified and shaped in the first and second amplifiers / equalizers 100 and 110, respectively, and then output in synchronization with the head switching signals H / SW. All operations below are consistent with the operation of the HD playback mode described above, and since only one part of the heads H1 and H2 operates, the first and second amplifiers / equalizers 100 and 110 and the first and second formatters 160 and 170 operate only half of the operation time in the HD playback mode.

In the prior art as described above, by recording only once on the tape, if the tape is damaged by scratching or the like, it cannot be restored again during playback; When the recording tape is low grade, there is a problem that the reliability of the data is lowered.

Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to provide an apparatus having a repetitive recording function in order to improve the reliability of data.

1 is an exemplary view showing the configuration of a conventional error correction code (ECC).

2 is an exemplary view showing an internal configuration of a track of a conventional digital recording / reproducing apparatus.

Figure 3 is an exemplary view showing the structure of the drum and the head of the two-channel V-Cal for recording the conventional high-definition data.

4A is an exemplary view showing a track shape in two channels according to FIG. 3;

4B is an exemplary view showing a track shape in one channel according to FIG. 3.

Figure 5 is an exemplary view showing the structure of a drum and a head of a two-channel BC for recording another high-definition data conventionally.

6A is an exemplary view showing a track shape in two channels according to FIG. 5;

6B is an exemplary view showing a track shape in one channel according to FIG. 5;

7 is a block diagram showing the configuration of a conventional two-channel recording / reproducing apparatus.

8 is a timing diagram showing an operation state of each regeneration mode according to the output of the head by the rotation of the conventional drum.

Fig. 9 is a block diagram showing the construction of one embodiment of the digital recording / reproducing apparatus of the present invention.

Fig. 10 is a block diagram showing the construction of one embodiment of the digital recording / reproducing apparatus of the present invention.

FIG. 11 is a block diagram illustrating an embodiment of an internal data selector in FIG. 10. FIG.

12 is a block diagram showing the configuration of an embodiment of the final output selector in FIG.

Figure 13 is a block diagram showing the configuration of one embodiment of the switching means in Figure 10;

FIG. 14 is an exemplary view showing a track in which SD data according to FIG. 3 is repeatedly recorded twice in HD mode using the present invention. FIG.

FIG. 15 is an exemplary view showing a track in which LP 1/3 data according to FIG. 3 is repeatedly recorded six times in HD mode using the present invention. FIG.

16 is an exemplary view showing a track in which LP 1/3 data according to FIG. 3 is repeatedly recorded three times in the SD mode using the present invention.

FIG. 17 is an exemplary view showing a track in which SD data according to FIG. 5 is repeatedly recorded twice in HD mode using the present invention. FIG.

18 is an exemplary view showing a track in which LP 1/3 data according to FIG. 5 is repeatedly recorded six times in HD mode using the present invention.

FIG. 19 is an exemplary view showing a track in which LP 1/3 data according to FIG. 5 is repeatedly recorded three times in the SD mode using the present invention. FIG.

20 is a table showing types of mode signals of an embodiment generated by the mode signal generator during recording;

21 is an operation timing diagram at the time of reproduction applied to FIG. 10;

Fig. 22 is an operation timing diagram at the time of overwriting by changing original recording data.

FIG. 23 is a diagram illustrating a format of a track to which FIG. 22 is applied. FIG.

FIG. 24 illustrates an embodiment in which the number of channels is reduced to one in the scheme of FIG. 10. FIG.

*** Description of the symbols for the main parts of the drawings ***

100, 110: first and second amplifiers / equalizers 120, 130: first and second restoration means

140, 150: first and second detection recording unit 190: interface unit

200, 210, 330, 340: Formatter 220: Final output sorting unit

230: mode selection means 240, 350: mode signal generator

250: servo 260: switching means

300,310: 1st, 2nd ECC unit 222, 261, 322: selection means

223, 262, 323: transmission means 221: data selection unit

321: internal data selection unit

The structure of the digital recording / reproducing apparatus of the present invention for achieving the above object comprises: an amplifier / equalizer for amplifying and shaping an input signal and outputting in synchronization with a head switching signal; Mode selection means for outputting a selection signal corresponding to the user's mode selection; A mode signal generator for generating a mode signal in accordance with a selection signal input from the mode selection means; Restoring means for restoring and outputting an input analog signal or a digital signal into a digital signal or an analog signal, respectively; A detection recording unit which detects the synchronization signal and the identifier signal from the digital signal input according to the mode signal generated by the mode signal generator, or attaches and outputs the synchronization signal and the identifier signal; According to the mode signal generated by the mode signal generator, the signal is converted into a predetermined format or restored to the same format as the signal input at the time of recording. A formatter to make; A final output selector for selecting error-free data according to a discrimination signal inputted from the formatter and the mode signal generator and a mode signal and a head switching signal and outputting a selection signal corresponding thereto; And switching means for selecting and outputting data input in accordance with the mode signal inputted from the mode signal generator.

Another configuration includes: a plurality of amplifiers / equalizers for amplifying and shaping an input signal and outputting the same in synchronization with a head switching signal; Mode selection means for outputting a selection signal corresponding to the user's mode selection; A mode signal generator for generating a mode signal in accordance with a selection signal input from the mode selection means; A plurality of restoring means for restoring and outputting an input analog signal or a digital signal into a digital signal or an analog signal, respectively; In response to the mode signal generated by the mode signal generator, a synchronization signal and an identifier signal are output by attaching a synchronization signal and an identifier signal, or a synchronization signal and an identifier signal are detected to determine whether there is an error of the synchronization signal and a corresponding signal (hereinafter referred to as "SYNC"). A plurality of detection recording sections for outputting an " error signal " A plurality of internal error correcting code units configured to internally correct an input digital signal in synchronization signal units, determine whether there is an error, and output a corresponding signal (hereinafter referred to as an "ECC error signal") and internal data; An internal data selection unit for selecting and outputting error-free data among the internal data by the mode signal, the SYNC error signal, and the ECC error signal inputted from the mode signal generator, the detection recording unit, and the internal error correction code unit; The data inputted according to the mode signal generated by the mode signal generator is converted into a predetermined format or restored to the same format as the signal input at the time of recording. A plurality of formatters for outputting missing data; A final output selector which selects and outputs data without error according to a discrimination signal input from the formatter and the mode signal generator and a mode signal and a head switching signal; And switching means for selecting and outputting data input in accordance with the mode signal inputted from the mode signal generator and the final output selector.

The internal data selector may include an internal data selector configured to output a signal for selecting internal data based on a mode signal, a SYNC error signal, a head switching signal, and an ECC error signal; Selecting means for selecting and outputting error-free data among internal data according to a selection signal of the internal data selecting unit; Characterized in that the transfer means for outputting the data output from the selection means to the formatter.

The final output selector comprises: a data selector for outputting a signal for selecting data to be output to the outside by a mode signal, a head switching signal and a data error signal; Selection means for selecting and outputting error-free data among data output from the formatter by a selection signal of the data selection unit; Characterized in that the transfer means for outputting the data output from the selection means to the switching means.

The switching means may include selecting means for selecting and outputting data received from a final output selection unit, a formatter and an interface unit according to a mode signal; Characterized in that the transfer means for outputting the data output from the selection means to the formatter and the interface unit according to the mode signal.

The mode signal generator further includes tape type discrimination means for discriminating the type of tape inserted into the recording and reproducing apparatus and outputting a signal corresponding thereto.

Hereinafter, an embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 9 is a block diagram showing an embodiment of the digital recording / reproducing apparatus of the present invention. First and second amplifiers for amplifying and shaping an input signal and outputting them in synchronization with a head switching signal as shown in FIG. Equalizers 100 and 110; Mode selection means 230 for outputting a selection signal corresponding to the user's mode selection; A mode signal generator 240 for generating a mode signal according to a selection signal input from the mode selection means 230; First and second restoring means for restoring an analog signal or a digital signal input from the first and second amplifier / equalizers 100 and 110 or the first and second detection recording units 140 into digital signals and analog signals, respectively; 120 and 130; First and second detection recording units 140 and 150 for detecting a synchronization signal and an identifier signal from data input according to the mode signal generated by the mode signal generator 240 or attaching and outputting the synchronization signal and the identifier signal; According to the mode signal generated by the mode signal generation unit (1), or converted to a predetermined format, or restored to the same format as the signal input at the time of recording, and then determine the error of the data according to the determination signal and error-free data First and second formatters 200 and 210 outputting the same; The final signal for selecting error-free data according to the discrimination signal inputted from the first and second formatters 200 and 210 and the mode signal generator 240, the mode signal, and the head switching signal, and outputting a corresponding selection signal. An output selecting unit 220; And switching means 260 for selecting and outputting data input in accordance with the mode signal input from the mode signal generator 240.

FIG. 10 is a block diagram showing an embodiment of the digital recording / reproducing apparatus of the present invention. First and second amplifiers for amplifying and shaping an input signal and outputting them in synchronization with a head switching signal as shown in FIG. Equalizers 100 and 110; Mode selection means 230 for outputting a selection signal corresponding to the user's mode selection; A mode signal generator 350 for generating a mode signal according to the selection signal input from the mode selection means 230; First and second restoring means (120, 130) for restoring and outputting the input analog signal or digital signal into a digital signal or analog signal, respectively; In response to the mode signal generated by the mode signal generator 350, a synchronization signal and an identifier signal are output to the digital signal inputted, or the synchronization signal and the identifier signal are detected to determine whether there is an error of the synchronization signal and corresponding signal ( First and second detection recording units 140 and 150 for outputting a " SYNC error signal " First and second internal error correcting codes for outputting the digital signal inputted by the internal error correction code in synchronization signal units and determining whether there is an error (hereinafter referred to as an "ECC error signal") and internal data. 300 and 310; The mode signal, the SYNC error signal, and the ECC error signal received from the mode signal generator 240, the first and second detection recording units 140 and 150, and the first and second internal error correction code units 300 and 310. An internal data selection unit 320 for selecting and outputting data having no error among the internal data; According to the mode signal generated by the mode signal generation unit 350, or converted to a predetermined format format, or restored to the same format as the signal input at the time of recording, and then determine the error of the data there is no discrimination signal and error First and second formatters 330 and 340 for outputting data; The final signal for selecting error-free data according to the discrimination signal inputted from the first and second formatters 330 and 340 and the mode signal generator 350, the mode signal and the head switching signal, and outputting a corresponding selection signal. An output selecting unit 220; And switching means 260 for selecting and outputting data input in accordance with the mode signal input from the mode signal generator 350.

FIG. 11 is a block diagram illustrating an embodiment of the internal data selection unit in FIG. 10, and outputs a signal for selecting internal data based on a mode signal, a SYNC error signal, a head switching signal, and an ECC error signal as shown in FIG. 10. An internal data selector 321; Selection means (322) for selecting and outputting error-free data among internal data according to a selection signal of the internal data selection unit (321); The transmission means 323 outputs the data output from the selection means 322 to the first and second formatters 330 and 340.

FIG. 12 is a block diagram illustrating an embodiment of the final output selector in FIG. 10. As shown in FIG. 10, data for outputting a signal for selecting data to be output to the outside by a mode signal, a head switching signal, and a data error signal is shown. A selection unit 221; Selection means (222) for selecting and outputting error-free data among data output from the first and second formatters (330, 340) by the selection signal of the data selection unit (221); It comprises a transmission means 223 for outputting the data output from the selection means 222 to the switching means 260.

FIG. 13 is a block diagram showing an embodiment of the switching means in FIG. 10. As shown in FIG. 10, the final output selector 220, the first and second formatters 330, 340, and the interface 190 are shown in FIG. Selecting means 261 for selecting and outputting input data according to a mode signal; The transmission means 262 outputs the data output from the selection means 261 to the first and second formatters 330 and 340 and the interface unit 190 according to the mode signal.

Referring to the operation process and effect of the embodiment according to the present invention configured as described above are as follows.

When the apparatus shown in FIG. 9 is applied to the head of the type shown in FIG. 3 when recording, the description of the present invention is largely divided into recording time and playback time. When the recording mode is selected, the mode signal generator 240 records the number of redundant recording times as set. If the SD data is recorded twice in the HD mode, the actual signal is recorded as shown in FIG. H1, H3) and the redundantly recorded portions (H2, H4) are alternately recorded, and if the LLP (LP) 1/3 data is repeatedly recorded six times in HD mode, one actual signal as shown in FIG. 15 is shown. Recorded part and 5 times duplicated parts are recorded alternately, and if LP 1/3 data is recorded 3 times in SD mode, as shown in FIG.It is locked.

In addition, when the apparatus shown in FIG. 9 is applied to the head of the type shown in FIG. 5, if the SD data is repeatedly recorded twice in the HD mode, the actual signal is recorded as shown in FIG. Partial and dummy parts are alternately recorded, and if LP 1/3 data is recorded six times in HD mode, as shown in FIG. 18, one real signal is recorded and five duplicated parts and two dummy are recorded. The parts are recorded alternately, and if LP 1/3 data is recorded three times in the SD mode, as shown in Fig. 19, the part where one actual signal is recorded and the part where two duplicated recordings are recorded are alternately recorded.

As described above, the mode signal generator 240 generates a corresponding mode signal according to the mode selection signal input from the mode selection means 230. For example, as shown in FIG. When the mode HD1 is selected through the selecting means 230, the signal HD is input from the mode selecting means 230 to the mode signal generator 240, thereby selecting the selectable recording mode HD and setting the number of duplicate recordings. In addition, the mode signal generator 350 shown in FIG. 10 sets the number of times of overwriting in a variable manner according to the type of tape to be inserted instead of setting a fixed number of times of overwriting, for example, a running time. The tape with 60 minutes) is duplicated twice, and the tape with 90 minutes running time is duplicated three times.

Referring to the operation process during reproduction of the present invention, FIG. 21 is an operation timing diagram during reproduction applied to FIG. 10, which is the same as the operation state shown in FIG. 8 as shown in FIG. 21A shows a case where the SD data is repeatedly recorded twice in the HD mode, and FIG. 21B shows a case where the LP 1/3 data is repeatedly recorded three times in the SD mode. In addition, FIG. 22 shows that the same type of data is not recorded on each track, but the original recorded data is changed and overwritten. The output signal of each unit is the same as that of FIG. 21, except that only the duplicate data is changed. For example, the case where the data of the form is repeated and the case where the modified data is recorded for each track are as follows.

The same type of data is repeated to repeatedly record LP 1/3 data in the SD mode three times, as shown in FIG. 23A, and when modified data is recorded for each track, as shown in FIG. 23B. The track data is shifted and recorded, where K denotes the amount of shift, and the sync number of the track does not exceed n.

FIG. 24 illustrates an embodiment in which the number of channels is reduced to one in the method of FIG. 10. The operations of the internal data selector 320, the final output selector 220, and the switching unit 260 are illustrated in FIG. 10. Same as the operation of the device.

As described above, the digital recording / reproducing apparatus of the present invention has a function of overlapping recording by the user's selection or the type of tape to be inserted, thereby improving data reliability and effectively coping with various tape grades. In addition, it can cope with harsh environment and can be used for information storage, and it can be applied as an additional function without changing existing specifications.

Claims (8)

An amplifier / equalizer for amplifying and shaping an input signal and outputting the same in synchronization with a head switching signal; Mode selection means for outputting a selection signal corresponding to the user's mode selection; A mode signal generator for generating a mode signal in accordance with a selection signal input from the mode selection means; Restoring means for restoring and outputting an input analog signal or a digital signal into a digital signal or an analog signal, respectively; A detection recording unit which detects the synchronization signal and the identifier signal from the digital signal input according to the mode signal generated by the mode signal generator, or attaches and outputs the synchronization signal and the identifier signal; According to the mode signal generated by the mode signal generator, the signal is converted into a predetermined format or restored to the same format as the signal input at the time of recording. A formatter to make; A final output selector for selecting error-free data according to a discrimination signal inputted from the formatter and the mode signal generator and a mode signal and a head switching signal and outputting a selection signal corresponding thereto; And switching means for selecting and outputting data input in accordance with a mode signal input from the mode signal generator. A plurality of amplifiers / equalizers for amplifying and shaping an input signal and outputting the same in synchronization with a head switching signal; Mode selection means for outputting a selection signal corresponding to the user's mode selection; A mode signal generator for generating a mode signal in accordance with a selection signal input from the mode selection means; A plurality of restoring means for restoring and outputting an input analog signal or a digital signal into a digital signal or an analog signal, respectively; In response to the mode signal generated by the mode signal generator, a synchronization signal and an identifier signal are output by attaching a synchronization signal and an identifier signal, or a synchronization signal and an identifier signal are detected to determine whether there is an error of the synchronization signal and a corresponding signal (hereinafter referred to as "SYNC"). A plurality of detection recording sections for outputting an " error signal " A plurality of internal error correcting code units configured to internally correct an input digital signal in synchronization signal units, determine whether there is an error, and output a corresponding signal (hereinafter referred to as an "ECC error signal") and internal data; An internal data selection unit for selecting and outputting error-free data among the internal data by the mode signal, the SYNC error signal, and the ECC error signal inputted from the mode signal generator, the detection recording unit, and the internal error correction code unit; According to the mode signal generated by the mode signal generator, the signal is converted into a predetermined format or restored to the same format as the signal input at the time of recording. A plurality of formatters; A final output selector for selecting error-free data according to a discrimination signal inputted from the formatter and the mode signal generator and a mode signal and a head switching signal and outputting a selection signal corresponding thereto; And switching means for selecting and outputting data input in accordance with a mode signal input from the mode signal generator. The display apparatus of claim 2, wherein the internal data selector comprises: an internal data selector configured to output a signal for selecting internal data by a mode signal, a SYNC error signal, a head switching signal, and an ECC error signal; Selecting means for selecting and outputting error-free data among internal data according to a selection signal of the internal data selecting unit; And transfer means for outputting data output from said selection means to a formatter. 3. The apparatus of claim 2, wherein the final output selector comprises: a data selector for outputting a signal for selecting data to be output to the outside by a mode signal, a head switching signal and a data error signal; Selection means for selecting and outputting error-free data among data output from the formatter by a selection signal of the data selection unit; And transfer means for outputting data output from said selection means to a switching means. 3. The apparatus of claim 2, wherein the switching means comprises: selection means for selecting and outputting data received from the final output selection unit, the formatter and the interface unit according to a mode signal; And transfer means for outputting the data output from the selection means to a formatter and an interface unit according to a mode signal. The digital recording / reproducing apparatus according to claim 2, wherein the mode signal generating unit further comprises tape type discriminating means for discriminating the type of the tape inserted into the recording / reproducing apparatus and outputting a signal corresponding thereto. 3. The digital recording / reproducing apparatus according to claim 2, wherein the mode signal generator selects one of a reproduction mode and a redundant recording mode according to the selection signal input from the mode selection means. The digital recording / reproducing apparatus according to claim 7, wherein the mode signal generator automatically resets the number of times of overwriting variably according to the type of tape.