JPH10247302A - Magnetic recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically erase remained record at first in the case of overlapping recording. SOLUTION: The information of the final recording position is read in from a MIC 14 by a system control circuit 20 before the overlapping recording is made. Immediately after the overlapping recording operation, the present tape position outputted from a recording/reproducing process circuit 16 is read in by the system control circuit 20 and written into the MIC 14 as the new final recording position. When the present tape position is smaller that the final recording position before the overrecording, an erase circuit 18 is instructed by the system control circuit 20 to start the erase. During the erase operation, the monitoring is made by the system control circuit 20 whether the erase operation by the erase circuit 18 is attained up to which track in accordance with the output of an adding device 24, than the erase by the erase circuit 18 is continued until the present tape position becomes equal to the final recording position before the overlapping recording. When the erase is executed up to the final recording position before the overlapping recording, the erase stop instruction is issued to the erase circuit 18 by the circuit 20 to complete the erasure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus for recording / reproducing information using a tape as a recording medium,
More specifically, the present invention relates to a magnetic recording / reproducing apparatus such as an audio tape recorder for recording / reproducing audio and a video tape recorder (hereinafter, VTR) for recording / reproducing video.

[0002]

2. Description of the Related Art At present, as a method of recording video in a VTR, not only recording on a non-recording tape but also overlapping recording on a recorded tape is possible. Thus, when the previously recorded video is no longer needed, another new video can be easily overlaid and recorded.

[0003]

However, when a new image is recorded on a tape on which an unnecessary image is recorded,
Unnecessary images remain behind the position where the overwriting has been completed. If you leave this unnecessary video without deleting it,
At the time of video reproduction, unnecessary video is reproduced immediately after the video to be viewed, so that the appearance was not good as a storage tape.

An object of the present invention is to provide a magnetic recording / reproducing apparatus which solves such a problem and automatically erases the remaining unnecessary portion from the position where the overwriting is completed when information is overwritten on the tape. With the goal.

[0005]

In order to achieve the above object, a magnetic recording / reproducing apparatus according to the present invention erases information from an end position of an overwrite recording to a predetermined position after overwriting information on a tape. Thus, when the information is overwritten on the tape, the remaining predetermined portion is automatically erased from the position where the overwriting is completed.

In addition, after information is overwritten on the tape, if information is recorded after the end position of the overwrite recording, the information is erased from the end position of the overwrite recording to a predetermined position. As a result, since no erasure is performed if no information is recorded from the position where the overwriting has been completed to the rest, there is no need to wait useless time.

[0007] Further, a storage means for storing information of a recording end position on the tape is provided, and after the information is recorded on the tape, when the recording end position is ahead of the recording end position,
Erases from the recording end position to the recording end position. As a result, if no information is recorded in the remaining portion from the position where the overwriting is completed, the information is not erased, and if the information is recorded, only that portion can be automatically erased.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic block diagram showing an embodiment of the present invention applied to a consumer digital VTR. 1
Reference numeral 0 denotes a tape cassette in which a magnetic tape 12 and a nonvolatile memory (MIC) 14 are housed. 16
Is a recording / reproducing processing circuit for recording / reproducing video / audio on the magnetic tape 12, 18 is an erasing circuit for erasing recorded information on the magnetic tape 12, 20 is a system control circuit including a microcomputer for controlling the whole, and 22 is an erasing circuit 18 Counter for counting the pulses output from the
This is an adder for adding the output value (count value) of No. 2 and the data output from the recording / reproducing processing circuit 16.

Since the present embodiment is a digital VTR, the erasing circuit 18 may not be necessarily provided if the recording / reproducing processing circuit 16 records no signal when erasing a recorded video.

FIG. 2 shows a track recording pattern of a consumer digital VTR. With reference to FIG. 2, a method of acquiring the current tape position in the present embodiment will be described. Tracks recorded on the magnetic tape 12 by the recording / reproducing processing circuit 16 include an ITI sector 30 in which a reference signal for after-recording or the like is recorded, an audio sector 32 in which an audio signal or the like is recorded, and a video signal. A video sector 34 and a subcode sector 36 in which a cue signal is recorded. In the subcode sector 36, an absolute track number (ATN) is recorded.

Normally, when recording an image, the recording / reproducing processing circuit 16 records signals of the respective sectors 30 to 36 while forming tracks on the magnetic tape 12 as shown in FIG. Is output to the system control circuit 20 and the adder 22. The system control circuit 20 stores the ATN data from the recording / reproducing processing circuit 16 as absolute position information of the current tape position. As a result, the system control circuit 20 can monitor how far the magnetic tape 12 has been recorded.

On the other hand, when erasing a recording, the erasing circuit 18 outputs a pulse to the counter 22 every time a track is erased. The counter 22 counts the pulses input from the erase circuit 18 and outputs the resulting count value (ie, the number of erase tracks) to the adder 24. The adder 24
The ATN data input from the recording / reproducing processing circuit 16 is added to the count value from the erasing circuit 18, and the addition result is applied to the system control circuit 20. Since the output of the adder 24 indicates the current tape position, the system control circuit 20 can monitor to which position on the magnetic tape 12 the erasing has progressed.

FIG. 3 shows an outline of a memory map of the MIC 14. The system control circuit 20 stores the ATN data at the recording end position of the magnetic tape 12 in the MIC 14. M
In the IC 14, addresses 0000H to 000FH are a main area for storing basic information on the magnetic tape 12, and others are optional areas. The system control circuit 20 stores the ATN data at the recording end position at addresses 000BH to 000EH in the main area.

FIG. 4 is a flowchart showing the operation of the system control circuit 20 at the end of recording. FIG. 5 shows an outline of a recording state of the magnetic tape 12. In the state before the overwrite recording (FIG. 5A), the MIC 14 stores the recording final position AT.
N = i is stored, and the system control circuit 20
The information i of the last recording position is read from the IC 14 (S
1). In the state immediately after the overwriting operation (FIG. 5B), the system control circuit 20 reads the current tape position ATN (j in FIG. 5) output from the recording / reproducing processing circuit 16 (S2) and newly reads this. MIC14 as the last recording position
(S3).

It is determined whether or not the current tape position j is smaller than the recording end position i before the overlap recording (S4). If j is smaller than i (S4), the system control circuit 20 instructs the erasing circuit 18 to start erasing (S5). During the erasing operation (FIG. 5 (c)), the system control circuit 20 monitors to which track the erasing circuit 18 has erased by the output of the adder 24. The current tape position k indicated by the output of the adder 24 is compared with the recording end position i before the overwriting (S7), and the erasing by the erasing circuit 18 is continued until k becomes equal to i (S6). If k becomes equal to i (S7), it means that all extra recordings after the overwriting have been erased, and an erasing stop command is issued to the erasing circuit 18 to terminate the erasing (S8). When the erasing is completed, the state is as shown in FIG.

[0017]

As can be easily understood from the above description, according to the present invention, when information is over-recorded on a tape on which information is previously recorded, the remaining unnecessary portion is automatically recorded from the end position of the over-recording. This is very effective in creating storage tapes.

If the information has been recorded after the overlap recording end position after the information has been overwritten on the tape, unnecessary portions behind the overlap recording end position are erased and the overlap recording is terminated. If no information is recorded behind the position, no erasure is performed, so that time and power consumption can be saved.

Further, a storage means for storing information on a recording end position of the tape is provided. When information is overwritten on the tape and the end position of the overwrite is ahead of the end position of the recording, the end position of the overwrite recording is provided. By deleting the recording from the position up to the final recording position before the overwrite recording, if there is no unnecessary recording after the position where the overwriting has been completed, the erasure is not executed.If there is unnecessary recording, the unnecessary recording is not performed. Since the erasure is performed only on the part, the time and the power consumption can be further saved.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of an embodiment of the present invention.

FIG. 2 is a schematic diagram of a recording pattern of a consumer digital VTR.

FIG. 3 is a schematic diagram of a memory map of the MIC 14;

FIG. 4 is an operation flowchart of the system control circuit 20 of the embodiment.

FIG. 5 is a tape 1 for explaining the operation of the present embodiment.
FIG. 3 is a schematic diagram showing a recording state of No. 2;

[Explanation of symbols]

 10: Tape cassette 12: Magnetic tape 14: Non-volatile memory (MIC) 16: Recording / reproducing processing circuit 18: Erasing circuit 20: Microcomputer 22: Counter 24: Adder 30: ITI sector 32: Audio sector 34: Video sector 36 : Subcode sector

Claims (3)

[Claims] 2. A magnetic recording and reproducing apparatus according to claim 1, wherein after the information is overwritten on the tape, a portion from the end of the overwriting to a predetermined position is erased. 2. When information is recorded after the end position of the overwrite recording after the information is overprinted on the tape,
2. The magnetic recording / reproducing apparatus according to claim 1, wherein a portion from an end position of the overwrite recording to a predetermined position is erased. 3. A recording device for storing information on a recording end position of the tape, wherein the predetermined position is a recording end position, and after recording information on the tape, the recording end position is the recording end position. The magnetic recording / reproducing apparatus according to claim 1, wherein, from a position ahead of the recording, the portion from the recording end position to the recording end position is erased.