JP2606305Y2 - Function switching device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a function switching device suitable for application to audio equipment such as a radio cassette recorder which can switch a plurality of functions.

[0002]

2. Description of the Related Art Conventionally, a plurality of functions (for example,
In an audio device having AM radio reception, FM radio reception, tape recording / playback, and the like), as a general method of switching functions, a microcomputer detects that a function switch (hereinafter, referred to as a “function key”) is pressed. At the same time, the microcomputer is configured to control the switching of functions. FIG. 3 (a)
1 shows a configuration example of a conventional function switching device, which is an audio device having four types of functions (clock display, AM radio reception, FM radio reception, and TV audio reception).

In FIG. 3A, a function key 2 is a switch operated for switching a function. Every time the function key 2 is pressed, the function is changed to clock display as shown in FIG.
AM radio reception → FM radio reception → TV audio reception → clock display → AM radio reception →..., And the display related to the switched function is displayed on the LCD display 3. The cassette recorder can be used with the function switched to the clock display function.

[0004]

In audio equipment, for example, a specific function is deleted by changing the specifications of the equipment. In order to delete a predetermined function, the specification of the microcomputer is usually changed. But,
It takes many days to change the specifications of the microcomputer, and it cannot be dealt with immediately. In addition, there has been a problem that the cost of parts increases due to an increase in the number of types of specifications.

In view of the above, the present invention provides a function switching device that can immediately cope with a case where a specific function is to be deleted due to a change in the specification of a device, using a common microcomputer.

[0006]

A function switching device according to the first aspect of the present invention is a function switching device for sequentially switching a plurality of functions of a device, and a function key operated to sequentially switch a plurality of functions. And a first switching signal generating circuit for generating one switching signal for switching a function each time a function key is operated, and performing control for sequentially switching a plurality of functions, and which function is switched to A function switching unit that outputs a plurality of signals capable of distinguishing between a plurality of functions, and a plurality of signals output from the function switching unit are switched to a signal level indicating a specific function of the plurality of functions. Regardless And a second switching signal generating circuit for automatically generating one switching signal from the second switching signal. The function switching unit includes one switching signal generated by the first switching signal generating circuit and a second switching signal. The control for sequentially switching the functions by one switching signal generated by the generation circuit is performed.

In the function switching device according to the second aspect of the present invention, in the second switching signal generation circuit, the plurality of signals output from the function switching unit are switched to signal levels indicating specific functions of the plurality of functions. Thereafter, a switching signal is generated after a predetermined time has elapsed.

A function switching device according to a third aspect of the present invention has a display for displaying information related to the function switched by the function switching unit, and is switched to a specific function before switching to the next function. In the period until, the display of at least a specific function of the display is stopped.

[0009]

According to the first aspect of the present invention, when a specific function is to be deleted, when the function is switched to the function to be deleted, a switching signal is automatically generated without any switching operation and the next signal is generated. Since the function is switched to the function, it is possible to avoid a schedule delay due to a change in the specification of the microcomputer.

According to the invention of claim 2, after switching to the function to be deleted based on the switching signal generated by the operation of the operating means, the switching signal can be detected by, for example, the function switching means after a lapse of a predetermined time. Since the switching signal is generated after that, the function to be deleted can be reliably switched to the next function.

According to the third aspect of the present invention, since the display is not performed while the function is switched to the function to be deleted, it is possible to prevent the inconvenience of displaying the function to be deleted.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a function switching device according to the present invention will be described below with reference to FIG.
In this example, four types of functions, "clock display" and "AM
Radio reception ”,“ FM radio reception ”,“ TV audio reception ”
, And the function of “TV sound reception” is deleted. In FIG. 1, parts corresponding to those in FIG. 3 are denoted by the same reference numerals, and detailed description is omitted.

In the figure, one terminal 2a of the function key 2 is connected to a power supply terminal 5a, and the other terminal 2b is grounded via a resistor 21. The connection point between the terminal 2b of the function key 2 and the resistor 21 is connected to the base of an NPN transistor 24 via a series circuit of a capacitor 22 and a resistor 23. Transistor 2
The base 4 is grounded via the cathode and anode of the diode 25. The collector of the transistor 24 is a terminal 1a of a microcomputer (hereinafter referred to as "microcomputer") 1.
And its emitter is connected to the terminal 1b of the microcomputer 1.

A pulse signal used as a switching signal for switching a function is output from a terminal 1a of the microcomputer 1. Further, when the pulse signal output from the terminal 1a is supplied to the terminal 1b of the microcomputer 1, the microcomputer 1 switches the function assuming that the switching signal is supplied.

The terminal 1c of the microcomputer 1 outputs a high-level "H" signal only when the function using the tuner is switched to "AM radio reception", "FM radio reception", or "TV audio reception". Terminal.
Terminal 1c is connected to the base of NPN transistor 7.

The base of the transistor 7 is connected via a resistor 6 to a power supply terminal 5a. Further, the emitter of the transistor 7 is grounded, and the collector is connected to the base of the PNP transistor 8. The emitter of transistor 8 is connected to power supply terminal 5a, and its collector is grounded via resistors 9 and 10. The connection point between the resistor 9 and the resistor 10 is connected to the base of the NPN transistor 11. The emitter of the transistor 11 is grounded, and the collector is connected to the power supply terminal 5 a via the resistor 12 and to the anode of the diode 14.

That is, a signal output from the terminal 1c of the microcomputer 1 passes through a first buffer circuit composed of a resistor 6, a transistor 7, and 8, and then a transistor 11, and resistors 9, 10, and 12. After the signal is inverted by the configured inverting circuit, the signal is supplied to the anode of the diode 14.

The terminal 1d of the microcomputer 1 is a terminal for outputting a high-level "H" signal only when the function is switched to the "AM radio reception" function. This terminal 1d is connected to the anode of the diode 15 via the resistor 17.

The terminal 1e of the microcomputer 1 outputs a high-level "H" signal only when the function is switched to the "FM radio reception" function. This terminal 1e is connected to the anode of the diode 16. The connection point between the terminal 1e and the anode of the diode 16 is connected to the power supply terminal 5b via the resistor 13.

The cathodes of the diodes 14, 15, 16 are commonly connected, and the common connection point is connected to the base of the NPN transistor 18. The emitter of the transistor 18 is grounded, and the collector is connected to the power supply terminal 5a via the resistor 19. In other words, the anode of the diodes 14, 15, 16 is used as an input and the transistor 1
A NOR circuit having eight collectors as outputs is configured. The cathode of the diodes 14, 15, 16 is the transistor 1
By being connected to the base of the transistor 8, the logical sum of the signals applied to the anodes of the respective diodes is supplied to the base of the transistor 18. Further, the supplied OR is inverted by an inverting circuit constituted by the transistor 18 and the resistor 19. Note that transistor 1
The base of 8 is grounded via a capacitor 30.

The collector of transistor 18 is connected to the base of NPN transistor 20. Transistor 2
The collector of 0 is connected to the terminal 1a of the microcomputer 1, and the emitter is connected to the terminal 1b of the microcomputer 1.

The collector of the transistor 18 is connected to the base of the transistor 27 via the resistor 26. The emitter of the transistor 27 is grounded, and the collector is connected to the base of the transistor 29 and to the power supply terminal 5a via the resistor. The emitter of the transistor 29 is connected to the power supply terminal 5a, and its collector is connected to the terminal 1f of the microcomputer 1. That is, the signal output from the transistor 18 is transmitted through the resistor 26 to the transistors 27 and 29 and the resistor 28.
It is supplied to a second buffer circuit constituted by the second buffer circuit, and supplied to the terminal 1f of the microcomputer 1 from the second buffer circuit.
The terminal 1f is a signal input terminal for controlling the display of the LCD display 3. When a low-level "L" signal is input, the display is performed, and a high-level "H" signal is input. If so, the display is stopped.

Here, the function switching operation will be described in detail with reference to FIG.

For example, when the display is switched to the "clock display", the signal SC1 supplied to the base of the transistor 24 is at the low level "L" as shown in FIG. 2A.

The signal ST1 output from the terminal 1c of the microcomputer 1 has a low level "L" as shown in FIG. 2B because the tuner is not used, and the signal ST1 is supplied to the anode of the diode 14. ST2 is at a high level “H” as shown in FIG.

The signal SAM output from the terminal 1d of the microcomputer 1 is at a low level "L" as shown in FIG. 2D because the signal SAM has not been switched to "AM radio reception". The signal SFM output from the terminal 1e of the microcomputer 1 is
Since it has not been switched to "FM radio reception", it is set to the low level "L" as shown in FIG.

Therefore, the signal SC2 supplied to the base of the transistor 18 is at a high level "H" as shown in FIG. 2F. Then, the signal SC3 output from the collector of the transistor 18 is at the low level “L” as shown in FIG. 2G.

Signal S input to terminal 1f of microcomputer 1
DP is obtained by obtaining the signal SC3 output from the collector of the transistor 18 through the second buffer circuit, and is set to the low level "L" as shown in FIG. 2H. As a result, a display relating to “clock display” is displayed on the LCD display 3.

In this state, when the function key 2 is pressed (time t1), the signal SC1 supplied to the base of the transistor 24 immediately goes to the high level "H", and thereafter, the level gradually decreases (FIG. 9). 2A). Therefore, the transistor 24 is turned on for a certain period,
The pulse signal output from the terminal 1a of the microcomputer 1 is supplied as a switching signal to the terminal 1b via the collector / emitter of the transistor 24. As a result, it is detected that the microcomputer 1 has performed the function switching operation, and the function switching is performed (time t2).

Here, the time from the time point t1 to the time point t2 shown in FIG. 2 is the time from when the function key 2 is pressed until the microcomputer 1 detects the function switching operation and performs the function switching. Note that Ts shown in the figure indicates the time during which the function key 2 is pressed.

When the function is switched to "AM radio reception" (time t2), the signal ST1 output from the terminal 1c is set to the high level "H" and supplied to the anode of the diode 14 because the tuner is used. The signal ST2 is set to the low level “L”. Also, terminal 1d
Is high level "H".
Since the signal SFM output from the terminal 1e is not "FM radio reception", the low level "L" is held. Therefore, the signal S supplied to the base of the transistor 18
C2 is held at a high level "H", and the signal SC3 output from the collector of the transistor 18 is held at a low level "L" as in the case of the "clock display" function. Similarly, the signal SDP input to the terminal 1f of the microcomputer 1
Is held at the low level “L”, and the LCD display 3 displays “AM radio reception”.

In this state, when the function key 2 is pressed (time t3), the function is switched to "FM radio reception" (time t4). At this time, since the signal ST2 is at the low level “L”, the signal SAM is at the low level “L”, and the signal SFM is at the high level “H”, the signal SC3 output from the collector of the transistor 18 is low. Similarly, the signal SDP input to the terminal 1f of the microcomputer 1 has the low level "L".
Is held, and a display related to “FM radio reception” is displayed on the LCD display 3.

Further, in this state, the function key 2
Is pressed (time t5), the function is switched to the function "TV sound reception" to be deleted (time t6). At this time, since the signals ST2, SAM and SFM are all at the low level "L", the signal SC2 is at the low level "L", and therefore the signal SC3 output from the collector of the transistor 18 is at the high level "H". You. The transistor 20 is turned on when the signal SC3 output from the collector of the transistor 18 is set to the high level "H", and the pulse signal output from the terminal 1a of the microcomputer 1 is supplied to the terminal via the collector and emitter of the transistor 20. 1b is supplied as a switching signal. As a result, it is detected that the microcomputer 1 has performed the function switching operation, and the function switching is performed, and the function is set to the “clock display” function (time t).
7).

Since the capacitor 30 is connected to the base of the transistor 18, the signal SC2 changes from the high level "H" to the low level "L" in a predetermined time, and is similarly output from the collector of the transistor 18. The signal SC3 is also changed from the low level "L" to the high level "H" for a predetermined time. Therefore, the transistor 20 is turned on after a predetermined time has elapsed since the function was switched.

When a pulse signal is input from the terminal 1a to the terminal 1b in order to prevent a malfunction, the microcomputer 1 keeps the level of SC1 in FIG. 2A for a predetermined time, for example, a certain time after the function key 2 is pressed. The next signal is not accepted during the time from when the function key 2 is pressed to when it falls to a certain level.

As a result, the switching signal can be supplied after the microcomputer 1 can detect the switching signal, and the function of "clock display" can be reliably switched from the function of "reception of TV sound".

Since the signal SC3 output from the collector of the transistor 18 is at the high level "H", during the period when the function "TV sound reception" to be deleted is switched (time t6 to time t8), The signal SDP input to the terminal 1f of the microcomputer 1 is set to the high level "H", the display of the LCD display 3 is stopped by the microcomputer 1, and the display relating to "TV sound reception" to be deleted is not performed.

As described above, according to the present embodiment, even if the function key 2 is pressed to switch from "FM radio reception" to "TV audio reception", the display automatically switches to the next "clock display". Since the display related to “TV sound reception” is stopped, the user does not feel any trouble. Further, the specifications of the microcomputer 1 are not changed.

In this embodiment, the microcomputer 1 controls the LCD.
Although the display on the display 3 is stopped, the display on the function to be deleted without stopping the display on the LCD 3 may not be displayed. Furthermore, in this example, the case of deleting the function of “TV sound reception” is shown, but the function that can be deleted is not limited to “TV sound reception”. That is,
If the input signal of the diode is set so that a high-level "H" signal is output from the NOR circuit composed of the diodes 14, 15, 16 and the transistor 18 when the function is switched to the function to be deleted, it is easy. Other functions can be deleted.

In addition to the case where one function is deleted from the four functions, it is needless to say that an arbitrary plural function can be similarly deleted from an arbitrary plural function.

[0041]

According to the first aspect of the present invention, when a specific function is to be deleted, when the function is switched to a function to be deleted by a function key, the function is automatically switched to the next function without any operation. Since it can be switched, it is possible to immediately respond to the specifications of the device without having to change the specifications of the microcomputer.
Therefore, it is possible to avoid a schedule delay due to a change in the specifications of the microcomputer, and to prevent an increase in component costs due to an increase in the specifications of the microcomputer.

According to the second aspect of the present invention, after the function is switched to the function to be deleted based on the switching signal generated by the operation of the operating means, a switching signal is generated after a predetermined time elapses. It is possible to reliably switch to the next function.

According to the third aspect of the present invention, no display is performed while the function is switched to the function to be deleted, so that the inconvenience of displaying the function to be deleted can be prevented.

Therefore, the present invention is suitable for application to an audio device which can use a plurality of functions by switching.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of a function switching device according to the present invention.

FIG. 2 is a diagram showing a signal state of each unit in one embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Microcomputer 1a, 1b, 1c, 1d, 1e, 1f Microcomputer terminal 2 Function key 3 LCD display 5a, 5b Power supply terminal

Claims (3)

(57) [Scope of request for utility model registration] 1. A function switching device for sequentially switching a plurality of functions of a device, a function key operated to sequentially switch the plurality of functions, and a function key for switching a function each time the function key is operated. A first switching signal generating circuit for generating one switching signal; a function switching unit for performing control for sequentially switching the plurality of functions and outputting a plurality of signals capable of determining which function has been switched to When a plurality of signals output from the function switching unit are switched to a signal level indicating a specific function of the plurality of functions, one switching signal is output from the plurality of signals regardless of operation of the function key. Self A second switching signal generating circuit that generates the switching signal, wherein the function switching unit generates one switching signal generated by the first switching signal generating circuit and a second switching signal generated by the second switching signal generating circuit. A function switching device for performing control for sequentially switching the functions by one switching signal. 2. The method according to claim 2, wherein the second switching signal generating circuit switches the plurality of signals output from the function switching unit to a signal level indicating a specific function of the plurality of functions, and after a predetermined time elapses, The function switching device according to claim 1, wherein the function switching device generates a switching signal. 3. A display for performing a display or the like related to the function switched by the function switching unit, wherein a period from when the function is switched to the specific function to when the function is switched to the next function is the display. 2. The function switching device according to claim 1, wherein the display of at least the specific function is stopped.