JP2968012B2 - Digital magnetic recording / reproducing device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital magnetic recording / reproducing apparatus capable of rewriting only subcode information such as a start ID indicating a tune start on a recording medium later.

2. Description of the Related Art Conventionally, an R-
The DAT can record a subcode such as a start ID and a program time together with a PCM audio signal as a main signal. The start ID indicates the beginning of a song, and a high-speed cue search can be performed by determining the start ID during fast-forwarding or rewinding the tape. Further, an after-recording function for rewriting only the sub-code without changing the main signal has been put to practical use.

However, the conventional digital magnetic recording / reproducing apparatus has the following problems. In the track format of the R-DAT, as shown in FIG. 4A, one track is composed of 196 blocks, and there are a subcode area and an ATF area before and after the main data area. Further, as shown in FIG. 4 (b), recording and reproduction are switched at high speed while the head travels one track in order to perform after-recording, and only the subcode area which is a part of already recorded data is switched. Is rewritten. Also,
The servo system controls the tape feed so that the head traces the track center using the ATF signal at the time of reproduction and after-recording. However, if dubbing is performed on an unrecorded area after the already recorded area, a recorded area with only the subcode area without ATF will be created.
Since F control cannot be performed, a random recording pattern that violates the format is created. In addition, since recording is performed subsequently to a portion in which only the sub-area is recorded, a large problem is caused that a large nozzle is generated during reproduction because the ATF is not continuous.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a digital magnetic recording / reproducing apparatus capable of stopping post-recording on a non-recording portion and preventing recording against a format. is there.

Means for Solving the Problems In order to solve the above-mentioned conventional problems, a digital magnetic recording / reproducing apparatus according to the present invention comprises a mechanism for supporting and running a magnetic tape and a start to a subcode area on the magnetic tape. Start to instruct post-record ID start
A subcode dubbing key such as an ID write key, a mechanism control section for controlling the mechanism means, an envelope detection section for detecting whether or not a recorded signal has already been recorded on the magnetic tape, and a start section.
It has a subcode control unit that sets subcode information to be recorded such as ID, and when the closed state of the start ID writing key is detected, the mechanism unit is operated by the mechanism control unit, and recording is performed by the subcode control unit. Set the subcode to perform, post-record the subcode,
A system controller for controlling so as to immediately stop the post-recording, rewind to the already recorded portion, and then stop when detecting that the envelope detection unit has entered the non-recording portion during post-recording. It is.

Operation With the above configuration, when the system controller detects the closed state of the start ID writing key, the mechanism control unit operates the mechanism means, sets the subcode to be recorded by the subcode control unit, and performs the subcode dubbing. As soon as the envelope detector detects that it has entered a non-recording area during post-recording, it immediately stops post-recording, rewinds to the already recorded part, and then stops. The recording of only the sub-code signal is not performed, and the recording contrary to the format can be prevented, and the problem that a large nozzle is generated at the time of reproduction can be solved.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of an R-DAT which is a digital magnetic recording / reproducing apparatus according to one embodiment of the present invention. In FIG. 1, an input terminal 1 is connected via an input amplifier 2 to an A / D converter 3 and further to a PCM encoder 4 at a subsequent stage, and an input signal input to the input terminal 1 is amplified by the input amplifier 2 Are converted into digital signals by the A / D converter 3 and are encoded by the PCM encoder 4. Mixer 5 is PCM
PCM connected to encoder 4 and subcode encoder 6
The outputs from the encoder 4 and the subcode encoder 6 are mixed. On the other hand, the separator 7 is a PCM decoder 8,
The D / A converter 9 in the subsequent stage is further connected to the output terminal 11 via the output amplifier 10 in the subsequent stage, and also connected to the sub-code decoder 12, and the reproduction signal from the separator 7 is decoded by the PCM decoder 8. At the same time, the subcode such as the start ID is decoded by the subcode decoder 12, and the reproduced signal decoded by the PCM decoder 8 is D / A
After being converted into an analog signal by the converter 9, the signal is amplified by the output amplifier 10 and output from the output terminal 11. Further, the mixer 5 is connected to the recording / reproducing switching unit 14 via the recording amplifier 13 at the subsequent stage.
The signal from the mixer 5 is amplified by the recording amplifier 13 and input to one terminal 14a of the recording / reproducing switching unit 14. The other terminal 14a of the recording / reproducing switching unit 14 is connected to the reproducing amplifier 15, and further to the subsequent separator 7,
The reproduction signal is amplified by a reproduction amplifier and output to the separator 7. Further, the common terminal 14c of the recording / reproducing switching unit 14 is connected to the rotary head 16a of the mechanism 16, and during recording, the terminal 14c
a, At the time of reproduction, it is switched to the terminal 14b and connected. The mechanism 16 includes a driving device for supporting and running the tape and a rotary head 16a. Envelope detector 1
Reference numeral 7 is connected to the output terminal of the reproduction amplifier 15 and detects whether or not recording has already been made on the magnetic tape from the reproduction signal. The subcode determining unit 18 is connected to the subcode decoder 12, and determines a subcode. The subcode control unit 19 is connected to the subcode encoder 6, sets subcode information to be recorded such as a start ID, and outputs the information to the subcode encoder 6. The mechanism control unit 20 controls the mechanism 16. The system controller 21 includes an envelope detection unit 17, a subcode determination unit 18, a subcode control unit.
The system includes a 19 and a mechanism control unit 20, and controls the operation of the entire system by a command from each switch. Start ID
Write key 22 is connected to system controller 21,
Instructs the start of post-recording of the start ID to the subcode area on the magnetic tape.

FIG. 1 shows the block configuration of the digital magnetic recording / reproducing apparatus configured as described above, FIG. 2 shows the operation of the system controller 21 in PAD, FIG. 3 shows the operation timing, and FIG. The operation will be described below with reference to FIG. 4 showing the timing of recording / reproduction switching during post-recording.

For example, as shown in FIG. 3 (a), there is a tape which has already been recorded halfway, and as shown in FIG. 3 (b), the start ID is written from a position less than 9 seconds before the end of the envelope. Is described. In FIG. 2, first, since the mode of the system controller is the stop mode, in the processing block 33, the mechanism 16 is set to stop by the mechanism control unit 20. When the system controller 21 detects the closed state of the start ID writing key in the determination block 34, the processing system sets the next system controller mode to the start ID writing mode in the processing block 35. In the processing block 24, the mechanism is controlled by the mechanism control unit 20.
16 is set to 1x speed running, and the start ID of the subcode recorded by the subcode control unit 19 in the processing block 25
Is set to 1 and dubbing is started from the position A in FIG. 3 (c).

When the envelope detecting section 17 detects that the recording section has entered the non-recording section at the position B in FIG. 3C during the after-recording operation, the processing mode of the next system controller is changed to the post-recording rewind mode in the processing block 29. By setting, the post-recording is stopped immediately. Processing block
At 30, the mechanism 16 is set to the low-speed rewind by the mechanism control unit 20, and it is confirmed that 2 seconds have elapsed at the discrimination block 31. After rewinding to the position C in FIG. 3 (c), in the processing block 32, the next system mode is set to the stop mode.

The discrimination block 26 and the block 27 set the stop mode when recording is performed for 9 seconds. In the case of the present embodiment, the dubbing is started from a position within 9 seconds.

In this way, it is possible to avoid a problem that only the subcode signal is recorded in the non-recording portion where the ATF is not recorded.

Effects of the Invention As described above, according to the present invention, when the system controller detects that the envelope detection unit has entered the non-recording section during post-recording, the system controller immediately stops post-recording and winds up to the already recorded part. Since the recording is stopped after returning, it is possible to prevent recording against the format, which is caused by performing post-recording on an unrecorded portion, and to prevent generation of large noise during reproduction.

[Brief description of the drawings]

FIG. 1 is a block diagram of an R-DAT which is a digital magnetic recording / reproducing apparatus according to an embodiment of the present invention, FIG. 2 is a PAD diagram showing the operation of the R-DAT, and FIGS. c) is the same R-DAT
4 (a) and 4 (b) are timing charts of the operation in FIG.
FIG. 6 is a timing diagram of a DAT track format and recording / playback switching at the time of post-recording. 16 …… Mechanism, 17 …… Envelope detector, 19 ……
Subcode control unit, 20 Mechanism control unit, 21 System controller, 22 Start ID write key

Claims (1)

(57) [Claims] 1. A mechanism means for supporting and running a magnetic tape, a subcode dubbing key such as a start ID write key for instructing a start ID dubbing start to a subcode area on the magnetic tape, and said mechanism. A mechanism control unit for controlling the means, an envelope detection unit for detecting whether or not the recorded signal has already been recorded on the magnetic tape, and a subcode control unit for setting subcode information to be recorded such as a start ID. When the closed state of the start ID writing key is detected, the mechanism means is operated by the mechanism control section, the subcode to be recorded is set by the subcode control section, and the subcode is post-recorded. When the envelope detection section detects that the recording section has entered the non-recording section, the Digital magnetic recording and reproducing apparatus and a system controller that controls so as to stop the dubbing is stopped after rewind to the portion which is already recorded on.