JPS58121163A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To eliminate the effect to a reproduced video signal for a system which performs the selection and display of a mode under the control of a microcomputer, by setting a mode display command signal at a constant level in a reproduction mode. CONSTITUTION:A microcomputer which functions as a system control circuit 1 selects a mode in response to the operation of a control button part 2 and at the same time supplies a mode display command signal to a display part 3 to perform the display of a mode. The output is stopped periodically for the mode command signal in other modes than the reproduction mode. As a result, the part 3 has a blinking display. While the display is performed during the output of the mode display command signal in a reproduction mode. Thus the part 3 glows, and the mode display command signal is set at a constant level. In such a way, the power supply voltage or the earth potential have no fluctuation to eliminate an effect to a reproduced video signal.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention includes an operation button section and a display section, and when a desired operation button of the operation button section is depressed, the operation button section operates in a corresponding desired mode and is displayed in the mode 1. The present invention relates to a magnetic recording/reproducing device that can perform the following operations.

Conventionally, this type of magnetic recording/reproducing device uses a microcomputer (hereinafter referred to as a microcomputer) as a system control circuit.
When a desired operation button of the operation button section is pushed, an operation command signal is generated accordingly, and this operation command signal is inputted to the microcomputer. At the same time, a mode display command signal is supplied to the display section to display the mode.

FIG. 1 is a circuit diagram showing an example thereof, in which 1 is a microcomputer, 2 is an operation button part, 3 is a display part, 21e...
...+2n is the operation button, 3ti+..., 31
n is a light emitting diode, 3211..., 3z
n 1B, each transistor, 411...+4
n are input and output terminals, respectively.

Is the 2nd IA the displayed waveform at the input/output terminal in Figure 1? FIG.

Next, the operation of this conventional technique will be explained.

In FIG. 1, each input/output terminal 411 of the microcomputer 1...
. . .+4H indicates each operation button 21. of the operation button section 2.・
・・・・・・．

2n and the valley transistor 321 of the display section 3.・・・・・・
, 32n base electrons. '1 foot, one terminal of the operation buttons 2i+...+2n is grounded, and the other terminal and the transistor 321. ...
..., 32n bases are each biased by a 10B source. Each transistor 321.・・・・・・、
The collector terminal of 32n is grounded 71, and the emitter terminal is a light emitting diode 311.・・・・・・3! .

? Connected to the 10B source via.

The operation unit 2 is a part for operating various recording modes such as recording, playback, fast forward, rewind, and stop, and has respective operation buttons 21.
1... Set each of the above modes to +2n,
An example of a friend is a push-button switch that closes only when suppressed. Incidentally, in order to enter the recording mode, press the record button and the play button.

In this conventional technique, the operation button 21.・・・・・・＋
2n is not pressed, the transistor 321 of the display section 3 corresponding to this is connected to the +BtiL source V.
．． ......, 32n is in the OFF state, and the light emitting diodes 3u+...+31n connected to the emitter terminals of these transistors do not emit light, or if any of the operation buttons is turned on. , this is detected by all microcontrollers 1 and 0
Corresponding to step 7'1, all the transistors in the fC display section 3 are turned on to cause the light emitting diode to emit light.

That is, operation button 21. When the force .
z+...+4n is supplied to the corresponding input/output terminal, and in response, the microcomputer 1 sends a mode display command signal from the same input/output terminal to the corresponding transistor of the display section 3, turning on all of these transistors. Brother photodiode ta
It's shining.

In this way, the input/output of the mode command (S- number) from the operation button part 2 and the mode display command signal to the display part 3 are performed through the same input/output terminals 4□, . . . +4n. Therefore, in order to turn off the transistor of the display section 3 that was previously on when another operation button is pressed,
The level of the corresponding input/output terminal of microcomputer 1 must be set to high level.

Therefore, the microcomputer 1 has all the input/output terminals 41. ··song.

4n periodically and press operation button 21.・・・・・・+2
The level of the input/output terminals other than the input/output terminal corresponding to the suppressed operation button of n is made to be the 10B power supply and the 9-high level. At this time, the input/output terminal of the microcomputer 1 corresponding to the operation button being suppressed is grounded and becomes low level. This makes it possible to determine which operation button is being pressed, and the corresponding input/output terminal of the microcomputer 10 is latched to a low level.

Next, I will look at the second section and explain it in more detail.

Now, set the operation button 21k, for example, the playback button, and set the time 11.
Up to this point, the input/output terminal 41 is at a high level in a mode other than the playback mode, and the transistor 321r is off. Assume that the voltage becomes a low level, the transistor 321 is turned on, and the light emitting diode 3u emits light.

Therefore, during a short period of darkness '1' from time t1 to time t2, the light emitting diode 311 emits light, and at time t2, all input/output terminals 41T...+4n are simultaneously opened and remain at the level. The transistor 321 is turned off and the light emitting diode 311i stops emitting light. At this time,
If the operation button section 2 is pressed and there is no companion operation button, the input/output terminal 41 becomes low level at time t3, and the transistor 3 is turned on again.
21 is turned on and the light emitting diode emits 5uHK light.

Next, at time t4 after the period T has elapsed, the input/output terminal 41 becomes high level again, the transistor 321 is turned off, and the light emitting diode 311 stops emitting light. If there is no operation button, time t5
At this point, the input/output terminal jhn becomes low level.

In this way, the input/output terminal 41 repeats the low level and the still level at a certain period, and if there is an operation button that is pushed out when the input/output terminal 41 becomes high level at time tlO, the input/output The terminal 41 maintains a high level and the light emitting diode 311 Ir1 does not emit light. The same applies to other modes. Therefore, the display section 30 light emitting diode 311 .・・・・・・
・,3,.

The operating mode is indicated by flashing periodically.
(!-Display.

By the way, in the playback mode, if periodic pulses are supplied from the input/output terminal of the microcomputer 10 to the transistor of the display section 3 and the light emitting diode is blinked, this periodic pulse will cause the 10B1 to change from the source voltage or ground potential. destabilize;
This casts a shadow W on the reproduced video signal and deteriorates its S/N. In reality, although the vibrations in the power supply voltage and ground potential due to the above-mentioned periodic pulses are slight, the reproduced video signal reproduced from the magnetic head is a weak 1g signal of about several mV. In modern fully integrated video cameras and video tape recorders, one board of the video signal circuit and the microcontroller must be installed extremely close to each other, so even the slightest fluctuations in the power supply voltage or ground potential can cause playback. It is an object of the present invention to eliminate the drawbacks of the prior art described above, and to eliminate vibrations in the power supply voltage and ground potential by the mode display command signal from the microcomputer during the playback mode, and to display the playback image. An object of the present invention is to provide a magnetic recording/reproducing device in which the ll4L1 operating voltage of a signal processing circuit can be made completely stable.

To achieve this purpose, this E! A is to set the priority of the playback mode lower than other modes, and when the operation button of the mode in the middle of the playback mode is suppressed, it is possible to immediately switch to that mode, and the mode display command in the playback mode is set. It is characterized by a device that can reduce the signal level to a single level.

It should be noted that mode priority +=next refers to the order of modes that are preferentially activated when different modes are designated at the same time, that is, when operation buttons for different modes are pressed at the same time.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 3 is a block diagram showing an embodiment of the magnetic recording/reproducing apparatus according to the present invention, and 6 is a mode command circuit including a display section including a 5μ operation button, and 6 is a mode change circuit, which corresponds to FIG. The same reference numeral t has been added to the parts.

In the figure, when a desired mode is commanded by the mode command circuit 5, a mode command signal A is supplied to the microcomputer 1,
The microcomputer 1 receives the mode change command signal Bi7-mode variable circuit 6.
At the same time, the mode display command signal A is supplied to the mode command circuit 5.

Mode change 1! l! The circuit 6 changes the operating mode of the magnetic recording/reproducing apparatus to the mode commanded by the mode command circuit 5 based on the mode change command signal B; Display the commanded mode based on ・, tJ, 4 'eiV
1 is a circuit diagram showing an embodiment of the microcomputer 1 and mode command circuit 5 in FIG. 3, in which parts corresponding to the first section are given the same reference numerals.

In this embodiment, five modes are possible: playback, recording, fast forward, rewind, and stop, and 21 is a playback operation button, and 22 is a recording Ii! Ii operation button, 23 is a fast forward button, 24 is a rewind button,
25-value stop button.

FIG. 5 is a waveform diagram showing @ signs appearing at each input/output terminal of the microcomputer 1 in FIG. 4.

FIG. 6 is a flowchart showing the operation of the microcomputer 1 in FIG. 4. Next, the operation of this embodiment will be explained. .

In Figures 4 and 6, microcontroller 1 is the star) (2
7) Then, first, it is determined whether the current mode (hereinafter referred to as current mode) is the recording mode (28). In addition, when in the recording mode, the VC is connected to the student mode input/output terminal 4.
1 and the recording mode input/output terminal 42 are at low level, and the light emitting diode 3u+312 is emitting light.

When the current mode is the recording mode, the microcomputer 1 connects each input/output terminal 41 . ......, level 45 is inserted (34). First, the level of input/output terminal 450 in stop mode is detected and it is determined whether or not the stop operation button 25 is pressed (35) . If the problem occurs, press the stop operation button 2.
If 5 is pressed, do not add stop processing (36),
Mode change circuit 6 (Figure 3) Sends the K mode Arashiwara Shikin @ number to set the stop mode, and at 10'', the stop mode input/output terminal 45 is latched to a low level and the light emitting diode 31 is turned on.
5t" is emitted. When the stop button 25 is not pressed, it is determined whether the recording mode input/output terminal 42 is at a low level (3T). Since the current mode is the recording mode, it is natural that the recording mode input/output terminal 42 is at a low level. Next, it is determined whether the reproduction mode input/output terminal 41 is at a low level (38).

In the case of C, naturally, the playback mode input/output terminal 41 is at a low level, and recording processing (39) is performed. Therefore, mode R
The additional circuit 6 maintains the current shade, that is, the recording mode, and maintains the playback mode input/output terminal 41 and the f4 image mode input/output terminal 42 at a low level, respectively, so that the light emitting diodes 3 and 312 emit light. do. The levels of the input terminals 41 and 420 at this time are at a low level as indicated by signal 816.17 in FIG.

Next, a case where the current mode is determined (2B) and is not the recording mode will be described. At this time, Kf4, input/output terminal 41
．． Either one of 4m and 44.45 is a low level.

First, check whether the record button 22 is pressed or not! −
Distinguish (29) o The microcomputer 1 detects the level of the input/output terminal, but in order to avoid complicating the explanation, below we will explain whether or not one operation button is being controlled. ``to determine the ``clothing.''

Is the record button 22'lt pressed, or is the record button 22
Even if is not pressed, if the current mode is not the playback mode (33) or in either case, open all input/output terminals of the microcomputer 1 other than the recording mode input/output terminal 42 and turn on the 1B power supply. 30), play button 21. It is determined whether the fast forward button 231, the rewind button 24, and the stop button 25 are pressed (31).

If neither operation button is pressed, all input/output terminals are at high level, and the microcomputer 1 is connected to the mode change circuit 6.
(FIG. 3) maintains the current mode without sending signal B, and also sets the level of the input/output terminal for the current mode to a low level to cause the light emitting diode to emit light again.

~9 For example, if the current mode is fast forward mode, all input/output terminals other than the recording mode input/output terminal 42 i-41゜43
144+ 4s tl- When opened to high level,
When none of the operation buttons 21, 23, 24, and 25 are pressed, the fast forward mode input/output terminal 4at' is set to a low level.

Therefore, the light emitting diode for the current mode at C (when the current mode is the fast forward mode as described above, the light emitting diode 323) blinks.

In determination (31), if another operation button is pressed, the input/output terminal of the microcomputer 10 for that operation button is latched to a low level, and the mode command color code is read into the microcomputer 1 <34).

Therefore, first, it is determined whether or not the stop button 2s is pressed (35
) and the stop button 2s is pressed, the change to stop mode (36) is performed. If the stop button 25 is not pressed, it is determined whether the record button 21 is pressed (37).At this time, since the current mode is a mode other than the recording mode, the record button 21 is not pressed. If <29
), since the determination (31) has been performed, it generally requests a change to the recording mode, and the determination (38) of whether the playback button 22 is pressed is % y e s N, A change to recording mode (39) is performed.

However, when requesting fast forward, rewind, or playback mode, the whale button 21 is not pressed, or
If you accidentally press the record button 21 when you shouldn't, press the record button 2! 'no' to determine whether or not the button was pressed fully (31), or to determine whether or not the playback button 22 was pressed (38)
', then it is determined whether or not the fast forward button 23 is pressed (40). If the n1 early bird button 23 is pressed, a change to the fast forward mode (41) is performed. Next, press rewind button 2.
4 is pressed (42), and if the rewind button 24 is pressed, a change to rewind mode (43) is performed, but if the rewind button 24 is not pressed, the mode is changed to rewind mode (43). There is only a case where only the playback button 22 is pressed, and therefore the mode is immediately changed to the playback mode without any discrimination (44).
will be carried out.

Next, a description will be given of the metal fitting when the current mode is the playback mode.

At this time, K determines whether or not the current mode is the recording mode (28), and determines whether or not the recording button 21 has been pressed (29).
) are all % n o l, and the result is % yes' when it is determined whether the current mode is the reproduction mode (33).

Kuni, each input/output terminal of microcomputer 1 41142943+4
The level of 4.4 seconds is detected, each mode command signal sound is read from the operation button section 2 (34), and the light is sequentially determined by the same process as explained when the current mode is the recording mode. If the stop mode input/output terminal 45, the recording mode input/output terminal 41% fast forward mode input/output terminal 43, and the rewind mode input/output terminal 44 are all at the tube level, the reproduction mode will not be maintained.

To summarize, (1) When the current mode is recording or playback mode, each input/output terminal of microcomputer 1 41.42.4144.45
level? Constant detection, stop mode input/output terminal 45% border mode input/output terminal 41% fast forward υ mode input/output terminal 4
1. Determine the level of fil at the rewind mode input/output terminal 44.

(2) When the current mode is other than recording, playback, or recording mode, open the input/output terminals other than the recording mode input/output terminal 41 of microcomputer 1 and set them to high level, then record! It is determined whether any operation button other than the il button 21 has been pressed.

If none of the operation buttons are pressed, the input/output terminal of the microcomputer 1 for the current mode is set to a low level.

If any operation button is pressed, the corresponding operation button is pressed.
The input/output terminal of the microcomputer 1 is latched to a low level, and the mode command signal is input to the microcomputer 1. From now on, it is determined which mode this input/output terminal is in (
Discrimination is made in the order described in 1).

As described above, the dust mode is maintained, or the current mode is changed to another mode. Unless otherwise specified, playback mode input/output terminal 4 of microcontroller 1
2 low level brazed light emitting diode 312 tL
It emits light all the time, and when the operation button for another mode is pressed, microcomputer 1 immediately detects this from the corresponding input/output terminal, changes from the playback mode to the other mode, and at the same time changes the input to microcomputer 10 for the other mode. Set the output terminal to low level and make the light emitting diode fully emit light.

On the other hand, when in a mode other than the current recording mode or playback mode, the input/output terminal of the microcomputer 10 for that mode is periodically opened to a high level, and the input/output terminal of the microcomputer 10 for that mode is periodically opened and set to a high level. For this purpose, the light emitting diode flashes periodically (signal 18.1920 in Figure 5).Then, the stop button 26 is used to determine whether the operation button has been pressed or not.
, recording N2'+, fast forward button 23, and rewind button 24 in the order of priority setting all stop mode, recording mode, fast forward mode, rewind mode, and playback mode. In order to periodically change the level of the input/output terminal, the mode with the highest priority must be set when the operation buttons of different modes are pressed at the same time. When the input/output terminal level of the microcomputer 10 for a high mode is low, even if you press the operation button for a mode with a lower priority, the mode with the higher priority will still be maintained. Therefore, if the desk mode is the highest priority mode, the current mode should be set to 1.
This is so that the mode can be changed to when the button is opened and another operation button is pressed.

Therefore, the priority of the playback mode is set to the lowest L9, and when the current mode is the playback mode, the playback mode output of the microcomputer 1 can always be set to a low level, and the pulse mode No display command signal is generated (fifth drawing signal 16).

As explained in #52 above, according to the present invention, all mode command signals are input from the operation button section, the mode is changed, and the mode command signal of the system control circuit is outputted to the mode display command signal. Input/output terminals for each mode are provided for common input/output of the mode display command signal and the playback mode, and the level of the mode display command signal in the playback mode is lower than that of the other modes. −
A magnetic recording and reproducing device which has excellent functions, except for the drawbacks of the prior art, in which the reproduction video signal does not become unstable due to the mode display command signal.
All can be provided.

[Brief explanation of drawings]

Figure 1 is a circuit diagram showing an example of a magnetic recording and reproducing device for binmai;
FIG. 2 is a waveform diagram showing the signals shown in FIG. 1, FIG. 3 is a block diagram showing an embodiment of the magnetic recording/reproducing apparatus according to the present invention, and FIG. 4 shows an actual hflJ of the main part of FIG. 3. Circuit diagram, 5th
The figure is a waveform diagram showing the signals of each part of Fig. 4, and Fig. 6 is a waveform diagram showing the signals of each part of Fig. 4.
3 is a flowchart showing the operation of the figure. 1...System control circuit, 2...Operation button section, 3...Display section. 114? Z another tIrj(5r4t(tbt7 fBnow fヮf
3 Illustration 4 Illustration

Claims (1)

[Claims] In a magnetic recording and reproducing device designed to display a selected mode along with a mode selection, a plurality of operating means generate a mode command signal when operated, and a mode display command signal is supplied to display the mode. It has a plurality of display means and a plurality of input/output terminals commonly connected to the operation means and the display means, and outputs the corresponding mode display command signal by inputting the mode command signal. system control means, and when the operation mode is not the reproduction mode, the output of the mode display command signal for the operation mode is periodically stopped, and the operation mode is set to the reproduction mode. 1. A magnetic recording and reproducing apparatus characterized in that the level of the mode display command signal in the reproduction mode can be kept constant by performing the operation while the mode display command signal is being outputted.