JPH04195786A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To make it possible to minimize the control of a microcomputer, reduce the number of components and hence embody simpler structure resultant from the reduction of said components by constituting an address counter with one circuit alone. CONSTITUTION:A preset address latch circuit 11 and a delay address latch circuit 12 are set by the address of a read address 15, using a microcomputer 27. An address counter is designed to consist of one circuit only, which generates required write and read addresses to record and reproduce PCM signals consecutively to a first memory and a second memory. This construction makes it possible to minimize the control by the microcomputer, and embody equivalent electronic editing functions with simple structure resultant from the reduction of the number of components.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention provides a method for recording PCM signals on the magnetic tape of a first DAT while running two or more digital audio tape recorders (hereinafter abbreviated as DAT) in synchronization. the second
The present invention relates to a magnetic recording and reproducing apparatus that can perform electronic editing such as digital dubbing from editing points registered on a DAT magnetic tape.

Conventional technology Analog tape recorders use two or more types of tape, and when performing editing in which the signal on one tape is replaced with the signal on the other tape in the middle, the editing point is determined while playing each tape. Hand-cut editing has been carried out by searching, cutting each tape at the editing point, and splicing them together.

However, with digital audio tape recorders, due to the structure of the signal format on the tape, cutting and connecting the tape causes signal dropouts, and the signal becomes discontinuous at the editing point, causing abnormal noise. Hand-cut editing is not possible. Therefore, 2
While running more than one DAT synchronously, the second DAT (
It is necessary to perform electronic editing such as digitally dubbing the reproduction signal on the magnetic tape of the first DAT (player) onto the magnetic tape of the first DAT (recorder) from the registered editing point. In the electronic editing method, in advance, a PCM signal obtained from a recorder is recorded in a second memory, and a PCM signal obtained from a player is recorded in a first memory. Then, using both memories, the PC of the second memory is used before the editing point.
Plays the M signal, and from the editing point, the PC of the first memory
Perform memory rehearsal such as playing the M signal,
After confirming the connection of sounds at the editing point, two or more DATs are run synchronously to perform the above-mentioned electronic editing.

An example of a magnetic recording/reproducing apparatus equipped with the above-mentioned conventional electronic editing function will be described below with reference to FIGS. 5 to 10.

FIG. 5 is a block diagram showing the configuration of an example of a conventional magnetic recording/reproducing device. FIG. 6 shows that in the apparatus of FIG.
12 is an operation flowchart when recording PCM signals before and after an edit point reproduced from a magnetic tape on the recorder side into a second memory. FIG. 7 is an operational flowchart when the same device records the PCM signals before and after the editing point reproduced from the magnetic tape on the player side into the first memory. FIG. 8 is an operational flowchart of memory rehearsal. FIG. 9 is an operation flowchart of electronic editing by digital dubbing. FIG. 1O is an operation timing chart in which the horizontal axis represents time and the shaded areas represent recording signals on the magnetic tape and PCM signals on the memory.

In FIG. 5, 1 is a digital audio data receiving circuit (hereinafter abbreviated as DIN), and 2.24 is a shift register that converts a serial PCM signal into a parallel PCM signal. 3 is a first memory capable of recording and reproducing PCM signals from the magnetic tape of the first DAT (player side); 23 is a magnetic tape 8 of the second DAT (recorder side);
This is a second memory capable of recording and reproducing PCM signals from. 4゜22 is a P/S shift register that converts parallel PCM signals to serial PCM signals, 5 is a fade-in,
A cross-fade circuit performs a fade-out process (hereinafter abbreviated as cross-fade process), and 6.25 is a signal processing circuit that generates a recording/reproducing signal for the magnetic tape. 7.26 is a magnetic head.

Reference numeral 9.17 is a timing generator that generates timing for recording and reproducing to the first memory 3 and the second memory 23. 10. An address counter 18 generates write and read addresses necessary for sequentially recording and reproducing PCM signals in the first memory 3 and the second memory 23. al is a write address signal generated by the address counter 1G, a2 is a read address signal generated by the address counter 10, and a3 is a write/read address signal generated by the address counter 18. 11. A preset address latch circuit 19 loads the read start address of the memory 3 and the second memory 23 of plan 1 into the address counter 10.18. Reference numeral 12 denotes a delay address latch circuit, which reads out the read addresses of the first memory 3 and the second memory 23.
The read address is set to have a certain amount of offset from the write address. 13 is an adder, and in order to have an offset, address counter 1
0 and each address of the delayed address latch circuit 12 are added. A selector 14 sequentially switches between a write address and a read address when recording and reproducing a PCM signal in the first memory 3. 15.20 is a read address latch circuit, and address counter 10.18
Latch the counted address.

I6 is a microcomputer (hereinafter abbreviated as microcomputer) which sets the preset address latch circuit ratio 19 and the delayed address latch circuit 12 based on the address of the read address counter 15.20.

21 is a D/A converter that converts the PCM signal into an analog signal. Switches SWI to SW4 are used to record PCM signals before and after the editing point reproduced from the magnetic tape on the player side into the first memory 3. The switch SW2 connects the second memory 23
This is for recording PCM signals before and after the editing point reproduced from the magnetic tape on the recorder side. The switch sw3 uses the PCM signals recorded in the first memory 3 and the second memory 23 to reproduce the PCM signal in the second memory 23 before the editing point, and reproduces the PCM signal in the first memory 23 from the editing point. In order to reproduce the PCM signal in memory 3, memory rehearsal is started. Furthermore, the switch SW4 is used to actually record the reproduced signal on the player's magnetic tape from the edit point onto the recorder's magnetic tape.

6 to 10, a to f are time information (time code) recorded on the magnetic tape, g to i are addresses of the write address signal a3 of the address counter 18, and j to 1 are address counter data. This is the address of the write address signal a1 of 0.

The operation of the magnetic recording/reproducing apparatus configured as described above will be described below.

First, the signal on the magnetic tape 8 of the second DAT' (recorder side) is demodulated by the signal processing circuit 25, and the demodulated P
The CM signal is converted into parallel data by the S/P shift register 24. Then, as shown in FIG. 6, the data converted as described above continues to be recorded in the memory 23 of plan 2 in accordance with the address of the write address signal a3 that sequentially counts up the address counter 18 (step 23). . Here, when switch SW2 is pressed (
Step 24), the microcomputer 16 receives the time code (time information) of the edit point on the magnetic tape 8 on the recorder side and the address h of the write address signal a3 of the second memory 23 latched by the read address latch circuit 20. (step 25). Then, calculate the recording end point i based on the address h (step 26),
The write address to the second memory 23 is the recording end point i
If it reaches (step 27), the timing generator 17 is controlled to prohibit recording (step 28).

Also, the address counter 18 is stopped (step 29
). Here, the PCM signals before and after the editing point of this registered write address are stored in the second memory 2.
Recorded to 3.

Similarly, after the PCM signal reproduced from the magnetic tape of the first DAT (player side) is received by the DINI, it is converted into parallel data by the S/P shift register 2. The data thus converted continues to be recorded in the first memory 3 in accordance with the address of the write address signal a1 which sequentially counts up the address counter IO shown in FIG. 5 (step 30). Here, the time code (time information) of the edit point e on the magnetic tape on the player side when the switch SW1 is pressed (step 31)
, and the address k of the write address signal a1 of the first memory 3 latched by the read address latch circuit I5 are stored in the memory of the microcomputer 16 (step 32).
. Then, the recording end point l is calculated based on the above address k (step 33), and when the writing address to the first memory 3 reaches the recording end point l (step 34), the timing generator 9 is controlled. Recording is prohibited (step 35). Also, the address counter 1G is stopped (step 36). Here, the PCM signals before and after the edit point k of the registered write address are recorded in the first memory 3.

When the switch SW3 is pressed, memory rehearsal is performed using the first memory 3 and the second memory 23. During memory rehearsal, as shown in Figure 8,
First, the read start address g of the second memory 23 is set in the preset address latch circuit 19 (step 37).
) and load it into the address counter 18 (step 3
8). Similarly, a read start address j is set in the preset address latch circuit 11 so that the edit point in the first memory 3 and the edit point in the second memory 23 coincide (step 39). Then, this is loaded into address counter 10 (step 40), and address counters 10 and 11 are started at the same time (step 41).
, play at normal speed.

When the editing point reaches or reaches k (step 42), the cross-fade circuit 5 fades out the PCM signal from the second memory 23, and fades out the PCM signal from the first memory 3.
The signal is played back by performing a cross-fade such as a fade-in to replace the sound (step 43). and the first
The read address counter 15 indicates that the recording end point i of the memory 3 of the memory 3 or the recording end point 1 of the memo January 3 of the measure 2 has been reached.
Alternatively, after checking with the address counter 20 (step 44), the address counter 10. 18 is stopped (step 45).

In the above operation, the PCM signal is transmitted to the D/A converter 2.
Monitor and confirm the analog signal converted via 1.
Check how the sounds are connected at the editing point.

If the switch SW4 is pressed, the magnetic tape 8 is actually
record. As shown in FIG. 9, to record on the magnetic tape 8, both the recorder side and the player side rewind the magnetic tape to a point before the editing point (step 16), so that the editing point e on the player side is changed to the editing point e on the recorder side. The magnetic tape 8 and address counter 10 are started in advance of the start (steps 17 and 18). Until the reproduced signal on the magnetic tape 8 on the recorder side reaches the editing point, the recorded signal demodulated by the signal processing circuit 25 and further modulated again by the signal processing circuit 6 is recorded on the same magnetic tape 8 as the reproduced signal. continues to record at the same position (step 19).

The reproduction signal from the magnetic tape on the player side is once recorded in the first memory 3 in accordance with the address of the write address a1 which is sequentially counted up by the address counter 10. Then, during playback, the time code (
Based on the time information), the microcomputer 16 sets an offset amount of Δt to the delayed address latch circuit 12 (step 20, FIG. 1θ). The adder 13 adds the offset amount and the address of the address counter IO, and reproduces the PCM signal from the first memory 3 according to the address of the read address signal a2 which is the addition result. When the magnetic tape 8 on the recorder side reaches the editing point (step 21), the PCM signal on the recorder side is faded out by the cross-fade circuit 5, and at the same time, the PCM signal on the player side is cross-faded by fading in ( Step 22). Thereby, the reproduction signal on the magnetic tape 8 on the recorder side is switched to the reproduction signal on the magnetic tape on the player side, and is recorded on the magnetic tape 8.

Problems to be Solved by the Invention However, in the conventional configuration described above, address counters 10. Il
1 is required, and the microcomputer 16 also has each address counter 10. However, there was a problem in that it required control over 18.

The present invention solves the above-mentioned conventional problems and aims to provide a magnetic recording/reproducing device which can be realized with less control from a microcomputer and with a reduced number of parts.

Means for Solving the Problems The magnetic recording and reproducing apparatus of the present invention includes a first memory capable of recording and reproducing PCM signals of a first digital audio tape recorder, and a first memory capable of recording and reproducing PCM signals of a second digital audio tape recorder. and an address counter that generates write and read addresses necessary for sequentially recording and reproducing PCM signals to and from the first and second memories. It has a configuration in which one circuit includes an address counter that generates write and read addresses necessary for sequentially recording and reproducing PCM signals in the memory.

According to the configuration of the present invention, less control from the microcomputer is required, and the electronic editing function equivalent to the conventional one can be realized with a simple configuration due to a reduction in the number of parts.

Embodiment Hereinafter, a magnetic recording/reproducing apparatus equipped with an electronic editing function according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a magnetic recording/reproducing apparatus according to the present invention. Figure 2 shows the PC before and after the editing point played back from the magnetic tape on the recorder side in the apparatus shown in Figure 1.
It is an operation flowchart when recording an M signal into a second memory. FIG. 9 is an operational flowchart for recording PCM signals before and after an edit point reproduced from the magnetic tape on the player side into the first memory, and FIG. 3 is an operational flowchart for memory rehearsal. FIG. 4 is an operation timing diagram in which time is plotted along the horizontal axis, and hatched portions are schematically shown as recording signals on the magnetic tape and PCM signals on the memory.

In Figure 1, 27 is a microcomputer (hereinafter referred to as
(abbreviated as microcomputer), the read address counter 15
The preset address latch circuit 11 and the delayed address latch circuit 12 are set according to the address. In addition, in FIG. 4 and FIG. 10 shown as a conventional example,
g to i are the addresses of the write address signal a1 of the address counter 10. Other configurations and features include:
This is the same as the conventional example shown in FIG.

The operation of the magnetic recording and reproducing apparatus equipped with this electronic editing function will be explained below with reference to flowcharts.

First, the signal on the magnetic tape 8 of the second DAT (recorder side) is demodulated by the signal processing circuit 25, and the demodulated P
The CM signal is converted into parallel data by the S/P shift register 24. Then, as shown in FIG. 2, the data thus converted continues to be recorded in the second memory 23 in accordance with the address of the write address signal a1 which sequentially counts up the address counter 10 (step 1). Here, when the switch SW2 is pressed (step 2), the time code of the edit point on the magnetic tape 8 on the recorder side, and the write address signal of the second memory 23 latched by the read address latch circuit 15. a
1 address h to the memory of the microcomputer 16 (
Step 3). Then, the recording end point i is calculated based on the address h (step 4), and when the write address to the second memory 23 reaches the recording end point i (step 5), the timing generator 17 is controlled. Recording is prohibited (step 6). Also, address counter 1o
(Step 7). Here, centering on the editing point of this registered writing address, check the PCs before and after it.
The M signal is recorded in the second memory 23.

Similarly, after the PCM signal reproduced from the magnetic tape of the first DAT (player side) is received by the DINI, it is converted into parallel data by the S/P shift register 2. Then, as in the case of the conventional example shown in FIG. 7, the data converted as described above continues to be recorded in the first memory 3 in accordance with the address of the write address signal a1 that sequentially counts up the address counter 1o. (Step 30
). Here, when the switch SW1 is pressed (step 31), the time code of the edit point e on the magnetic tape on the recorder side and the write address signal a1 of the first memory 3 latched by the read address latch circuit 15 are Address k is stored in the memory of microcomputer 1f+ (step 32). Then, based on the above address k, the recording end point l
(step 33), and when the write address to the first memory 3 reaches the recording end point l (step 3).
4) The timing generator 9 is controlled to prohibit recording (step 35). Also, the address counter 1o is stopped (step 36). Here, the PCM signals before and after the edit point k of the registered write address are recorded in the first memory 3.

When the switch SW3 is pressed, memory rehearsal is performed using the first memory 3 and the second memory 23. During memory rehearsal, as shown in Figure 3,
Second memory 23 to preset address latch circuit If
The read start address g is set (step 8) and loaded into the address counter 1G (step 9). Similarly, at the edit point of the first memory 3 and the edit point of the second memory 2,
The microcomputer 27 calculates the offset amount of ΔX and sets the delay address latch circuit 1 so that the editing points of 3 match.
Set to 2. (Step lO1 Figure 4) Next is the address counter! 0 (step 11) and playback at normal speed. When the editing point is reached (step 12)
, the cross-fade circuit 5 performs a cross-fade such that the PCM signal from the second memory 23 is faded out and the PCM signal from the first memory 3 is faded in, and the sounds are replaced and reproduced (step 13).

After confirming with the read address counter 15 that the recording end point 1 of the second memory 23 has been reached (step 14),
Address counter 10 is stopped (step 15).

In the above operation, the PCM signal is transmitted to the D/A converter 2.
Monitor and confirm the analog signal converted via 1.
Check how the sounds are connected at the editing point.

If the switch SW4 is pressed, the magnetic tape 8 is actually
record. As in the case of the conventional example shown in FIGS. 9 and 1O, to record on the magnetic tape 8, both the recorder side and the player side rewind the magnetic tape to a point before the editing point (step 16). The magnetic tape 8 and address counter 10 are started so that the editing point e precedes the editing point on the recorder side (step 17.1).
8). Until the reproduced signal on the magnetic tape 8 on the recorder side reaches the editing point, the recorded signal demodulated by the signal processing circuit 25 and further modulated again by the signal processing circuit 6 is transferred to the same magnetic tape 8 as the reproduced signal. Continue recording at the same position (step 19).

The reproduced signal from the magnetic tape on the player side is once recorded in the first memory 3 in accordance with the address of the write address signal a1 which is sequentially counted up by the address counter 10. Then, during playback, the microcomputer 16 offsets Δt based on the time code (time information) on the magnetic tape on the recorder side and the player side, so that the edit point on the recorder side matches the edit point e on the player side. Set the amount to the delayed address latch circuit 12 (Step 20, FIG. 10) The adder 13 adds the offset amount and the address of the address counter 10, and according to the address of the read address signal a2 which is the addition result. Then, the PCM signal is reproduced from the first memory 3. When the magnetic tape 8 on the recorder side reaches the editing point (step 21), the PCM signal on the recorder side is faded out by the cross-fade circuit 5, and at the same time, the PCM signal on the player side is cross-faded by fading in ( Step 22). Thereby, the reproduction signal on the magnetic tape 8 on the recorder side is switched to the reproduction signal on the magnetic tape on the player side, and is recorded on the magnetic tape 8.

As described above, according to this embodiment, the player side.

The number of parts can be reduced by providing only one address counter circuit for each memory on the recorder side. Furthermore, since the microcomputer 16 only controls one circuit of address counters, it is possible to provide a magnetic recording and reproducing device with an electronic editing function with less control.

Effects of the Invention The magnetic recording/reproducing device of the present invention requires less control from a microcomputer, has a simple configuration with a reduced number of parts, and can realize the same electronic editing function as the conventional one. The effect is great.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a magnetic recording/reproducing apparatus according to an embodiment of the present invention. FIGS. 2 and 3 are operational flowcharts of the device. FIG. 4 is an operation timing diagram of the device. FIG. 5 is a block diagram showing the configuration of an example of a conventional magnetic recording/reproducing device. 6 to 9 are operational flowcharts of the apparatus of FIG. 5. FIG. 1θ is an operation timing diagram of the device shown in FIG. 1...Digital audio data receiving circuit (DIN
), 3... First memory, 5... Cross fade circuit, 6, 25... Signal processing circuit, 7, 26... Magnetic head, 8... Magnetic tape, 10... Address Counter, 27... Microcomputer, 23... Second memory. Agent Yoshihiro Morimoto Figure 1 Figure 2 Figure 3 Shizuka Figure 1 Figure 7

Claims (1)

[Claims] 1. First digital audio tape recorder PC
A first memory capable of recording and reproducing M signals, a second memory capable of recording and reproducing PCM signals of a second digital audio tape recorder, and sequentially recording and reproducing PCM signals in the first and second memories. write necessary for,
A magnetic recording device comprising an address counter that generates a read address, and in which the address counter that generates write and read addresses necessary for sequentially recording and reproducing PCM signals in the first and second memories is configured as one circuit. playback device.