JPH07302483A - Magnetic recording/reproducing device - Google Patents

Abstract

PURPOSE:To prevent erroneous operation of recognition due to erroneous system information by actuating a transfer circuit by the backup of a second built-in power source even when the power source is interrupted under condition of a cassette being inserted. CONSTITUTION:The output of a first power source 1 supplied through a power source line 9a and that of a second power source 2 supplied through a power source line 9b are inputted into a switching circuit 4 and further supplied to a buffer 5 and a transfer circuit 6 through power source lines 9d, 9e. In addition, the output of the first power source 1 is inputted into a voltage monitoring circuit 3 through a power source line 9c to be compared with a reference voltage Vref. The voltage monitoring circuit 3 supplies input switching control signals 10 to the switching circuit 4, and the transfer circuit 6 is connected with a MIC(memory in cassette) 7 and a buffer 5 to which system information 8 is inputted from a recording/reproducing circuit (not shown in the figure). This constitution can prevent erroneous operation caused by erroneous information recorded in the MIC at the time of reuse of a cassette.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording system using a MIC (memory-in-cassette) having a semiconductor memory built in a cassette housing as a recording medium.

[0002]

2. Description of the Related Art An IC having a so-called system information, such as information (title, total time, etc.) for searching video and audio stored in a digital VTR, recording information (date, time, etc.) in a cassette housing. A magnetic recording system has been proposed which uses a medium having an MIC (Memory incasette) stored in a memory.

In a conventional magnetic recording system, a user manually writes, for example, system information on a label after recording and obtains desired information based on the system information. However, it takes time to manually enter the information, and an error may occur. Because of the large number, it was not always used properly. Also some VTR
In some cases, the system information is magnetically recorded in a specific area (for example, the head area) of the tape or is reproduced, but the tape is rewound to a predetermined position (for example, the head) each time it is reproduced. Needed and lacked speed.

On the other hand, in the magnetic recording system having the MIC, the system information is automatically recorded in the MIC, so that the above-mentioned trouble is unnecessary, and the outline of the information in the cassette can be quickly obtained. can do. further,
Based on that information, there is an advantage that the cassette that the user is looking for can be found, and the recording / reproducing can be performed by quickly moving to the desired area in the cassette.

[0005]

However, as described above, although the MIC information has many advantages when it is used, on the contrary, if proper information is not recorded, it leads to an erroneous operation, which causes a problem. Will end up. In particular, if the information in the unrecorded area is erroneously stored, it causes a trouble such as erasing the recorded portion up to the previous time when it is reused.

Conventionally, the system information is stored in a buffer in the magnetic recording / reproducing apparatus, the writing to the MIC is performed at a proper time, and finally, when the system recognizes the cassette ejecting operation, the MIC is rewritten. It was supposed to start ejecting.

However, if the outlet is unplugged while the cassette is inserted, or the power supply to the device is cut off due to a power failure or the like, the magnetic field in which the system information is stored immediately before the device is stopped without rewriting the MIC information. Since the contents of the buffer in the recording / reproducing apparatus are cleared, the system information immediately before the power interruption occurs cannot be transmitted and recorded in the MIC.

Therefore, the present invention solves the above problems,
If the power is cut off during operation of the magnetic recording / reproducing device,
It is an object of the present invention to provide a magnetic recording / reproducing device capable of reproducing and utilizing normal system information.

A further object of the present invention is to provide a magnetic recording / reproducing apparatus which does not erase the recorded area by mistake.

[0010]

In order to achieve the above object, a magnetic recording generator according to the present invention comprises a memory-in-cassette (hereinafter simply referred to as "M
(Hereinafter, abbreviated as "IC") as a recording medium, a buffer for storing and holding system information, a first power supply which is a power supply for the magnetic recording and reproducing apparatus, and system information stored in the buffer in the MIC. A transfer circuit for transferring and a second power supply, wherein the second power supply backs up the power supply of the buffer and the transfer circuit when the first power supply is cut off, and transfers the system information stored in the buffer to the MIC. Is.

Further, in the present invention, preferably, a voltage monitoring circuit for monitoring the first power-off, and a buffer and the M when the first power-off is instructed by the voltage monitoring circuit.
A switch circuit for switching the power supply of the IC transfer circuit from the first power supply to the second power supply is provided.

Further, in the present invention, the system information preferably includes at least information for distinguishing a recorded area and an unrecorded area of the recording medium.

Further, in the present invention, the second power source for backing up the power source of the buffer and transfer circuit when the first power source is shut off is preferably a built-in battery power source built in the magnetic recording / reproducing apparatus.

[0014]

According to the magnetic recording / reproducing apparatus of the present invention having the above structure, it is provided with a buffer for storing system information and a second power source for backing up a transfer circuit for transferring the system information to the MIC. Even when the first power supply is suddenly cut off unexpectedly, the buffer and the transfer circuit are activated by the power supplied from the second power supply, and the system information immediately before the first power supply cutoff is saved in the MIC.

As described above, since the system information is not lost even when a power failure occurs, the next recording / reproducing operation will be performed.
The system information saved in the MIC of the recording medium is reproduced,
Based on this information, recording at a predetermined position on the recording medium and reproduction from the predetermined position (for example, the head position of the unrecorded area) can be accurately performed.

Further, even when normal recording is not performed on the recording medium due to the stop of power supply, the video / audio information is temporarily held in the buffer, and the video / audio information is further transferred by the transfer circuit and recorded in the MIC. You can also It can be used as accurate search information when reused.

The second power source for backing up the buffer and the transfer circuit is preferably a small portable power source such as a battery or a dry battery incorporated in the magnetic recording / reproducing apparatus, and the miniaturization of the entire apparatus can be realized.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the magnetic recording / reproducing apparatus of the present invention. In the figure, reference numerals 9a, 9b, 9c and 9d connecting the respective blocks indicate power supply lines, and reference numerals 8, 10, and 11 indicate control signal and data lines.

The circuit configuration will be described with reference to the block diagram of FIG. As shown in the figure, the output of the first power supply 1 (power supply line 9a) and the output of the second power supply 2 (power supply line 9b) are input to the switch circuit 4, and the output of the switch circuit 4 (power supply lines 9d and 9e). Supplies power to the buffer 5 and the transfer circuit 6, and the first power supply 1 is connected to the voltage monitoring circuit 3
Is input (power supply line 9c) and compared with the reference voltage Vref, the voltage monitoring circuit 3 supplies the input switching control signal 10 to the switch circuit 4, and the transfer circuit 6 receives the trigger signal 11 and the transfer circuit. 6 is buffer 5 and M
Connected to the IC 7, the system information 8 is input to the buffer 5 from a recording / reproducing circuit (not shown).

Normally, the switch circuit 4 selects the first power supply 1 side, and the first power supply 1 is the power supply for the entire circuit. Then, at a predetermined timing, the system information is constantly transmitted / recorded from the recording / reproducing circuit (not shown) to the buffer 5, and the system information 8 is transferred and recorded from the transfer circuit 6 to the MIC 7 at the end of the recording / reproducing or immediately before the cassette is taken out. Has been done.

The voltage monitoring circuit 3 compares the supply voltage of the first power supply 1 with the reference voltage Vref, and if the supply voltage is lower than the reference voltage, the voltage monitoring circuit 3 switches the switch circuit 4
The input switching signal 10 to is activated.

The switch circuit 4 switches from the first power source 1 to the second power source 2 which is a built-in battery power source of the magnetic recording / reproducing apparatus, and outputs this as a power source to the buffer 5 and the transfer circuit 6. In addition, the transfer circuit 6 sends a clock to the buffer 5 to read the latest system information 8 stored in the buffer 5, and transfers this system information 8 to the MIC 7, in response to a trigger signal 11 from the voltage monitoring circuit 3.
The system information 8 is stored in the MIC 7.

As described above, the operation of the magnetic recording / reproducing apparatus according to the present embodiment allows MI to operate even if power is cut off due to disconnection of an external outlet, power failure, short circuit in the recording apparatus, or the like.
Since the latest system information before power off is saved in C,
It is possible to prevent an erroneous recognition operation which is recorded in the MIC when the cassette is reused, for example, due to incorrect system information immediately before.

In particular, if the recorded area of the cassette (recording medium), for example, the number of tracks is recorded in the MIC as the system information, the distinguishing information between the recorded area and the unrecorded area of the recording medium can be clarified. It is possible to prevent troubles such as overwriting and erasing the recorded part up to the previous time when using.

Further, since the system information can be surely backed up to the MIC by the second power source, due to an erroneous transmission which occurs when transmitting to the MIC when the power is cut off, which is a problem in the conventional magnetic recording system. It is also possible to prevent the destruction of normal information in the MIC. Further, if the image for the index is recorded in the MIC as the system information, the information value as the index is higher. Further, the image information is preferably a reduced / compressed image. This is because if it can be used as an index, the amount of information to be recorded will be reduced.

FIG. 2 is an external view showing a digital VTR standard cassette 20 having a MIC memory terminal 21, which is preferably used in one embodiment of the present invention.
It is a top view and (b) front view. According to the standard, the four electrodes are ground, power, clock, and data memory terminals 2 for data, respectively.
It is 1. These memory terminals 21 are connected to the transfer circuit 6 respectively.
Connected to. System information is data memory terminal 2
It is stored in the MIC 7 through 1.

FIG. 3 is an explanatory view showing an embodiment of the data format of the MIC. The data format is 5 bytes per unit according to the standard, and the first 1 byte is the header, followed by 4
This is index information indicating the type of byte data.

In this 4-byte portion, arbitrary information shown in the header can be written. In this embodiment, the recorded or reproduced track position, title, recording date / time, audio / image signal, etc. are recorded as system information.

When a voice / image signal is recorded in the MIC as the system signal as the system information, an operation such as a search for reusing the cassette as the index signal is simplified and speeded up.

Although the present invention has been described with reference to the embodiments,
The present invention is not limited to the above embodiments, but includes various embodiments according to the principle of the present invention.

[0032]

As described above, according to the present invention,
Even when the power is cut off in the cassette inserted state, the power supply backup by the second built-in power supply activates the buffer for temporarily storing the system information and the transfer circuit for transferring the system information to the MIC.
Since normal system information immediately before power-off can be transferred to and recorded in the IC, erroneous recognition operation due to incorrect system information recorded in the MIC when the cassette is reused can be prevented. Further, even if the first power supply is cut off while transferring the system information to the MIC, the second power supply such as a battery transfers the system information, so that a malfunction at the time of transfer is avoided and the information in the MIC can be surely protected.

In particular, when the discrimination information of the recorded area and the unrecorded area is recorded as the system information, the discrimination information of the recorded area and the unrecorded area can be clarified. It is possible to prevent problems such as accidents.

In particular, when the second power source for backing up the power source of the buffer and transfer circuit when the first power source is shut off is the built-in battery power source built in the magnetic recording / reproducing apparatus, the entire apparatus can be downsized.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of a magnetic recording / reproducing apparatus of the present invention.

FIG. 2 is preferably used in an embodiment of the present invention,
It is an external view which shows the digital VTR standard cassette 20 which has MIC, (a) top view, (b) front view.

FIG. 3 is an explanatory diagram showing an example of a data format of a memory (MIC) with a built-in cassette.

[Explanation of symbols]

1 1st power supply 2 2nd power supply 3 voltage monitoring circuit 4 switch circuit 5 buffer 6 transfer circuit 7 MIC 8 system information 9a, 9b, 9c, 9d, 9e power supply line 10 input switching control signal (from voltage monitoring circuit 3 to switch circuit 4 Signal to 11) transfer trigger signal (signal from voltage monitoring circuit 3 to transfer circuit 6) Vref reference voltage

Claims (4)

[Claims] 1. A magnetic recording system using, as a recording medium, a memory-in-cassette (hereinafter simply referred to as "MIC") containing at least a semiconductor memory, a buffer for storing and holding system information, and a magnetic recording / reproducing apparatus. A first power supply that is a power supply; a transfer circuit that transfers the system information stored in the buffer to the MIC; and a second power supply. When the first power supply is shut off, the second power supply is the buffer. And backup the power supply of the transfer circuit,
A magnetic recording / reproducing apparatus, wherein the system information stored in the buffer is transferred to an MIC. 2. A voltage monitoring circuit for monitoring interruption of the first power supply, and a power supply for the buffer and the MIC transfer circuit from the first power supply when the first power supply is cut off according to a command from the voltage monitoring circuit. The magnetic recording / reproducing apparatus according to claim 1, further comprising a switch circuit for switching to a second power source. 3. The magnetic recording / reproducing apparatus according to claim 1, wherein the system information includes at least information for discriminating a recorded area and an unrecorded area of the recording medium. 4. The magnetic recording / reproducing apparatus according to claim 1, wherein the second power source is a built-in battery power source of the magnetic recording / reproducing apparatus.