JPH0625959B2 - Input device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an input device having a key such as a membrane.

Conventional technology In recent years, even in high-frequency heating devices, the use of microcomputers,
Although complicated cooking sequences and various sensors are applied, in general, equipment having a control circuit device including a microcomputer is equipped with an input keyboard for transmitting the intention of the outside, especially the operator. An operation unit is provided.
In the conventional key input system, as shown in FIG. 7 (a), by forming a matrix circuit with the output signal system and the input signal system of the microcomputer, it is possible to determine what the key-in input is to the keyboard 6. The key-matrix method to know is the mainstream. There are a minute switch and a membrane structure as a constituent of the switch part of the key-matrix type keyboard. In particular, a membrane structure is preferred in terms of design feeling and flexibility.

Problems to be Solved by the Invention However, in this key matrix method, if the operation content becomes complicated, the number of keys on the keyboard 6 increases correspondingly, and it becomes difficult to handle the key input. This is because the input terminals of the microcomputer itself are limited (mainly 4 input terminals), and if the output terminals for output signals are frequently used, other output terminals for the intended control content will be insufficient,
There is a possibility that control will not be possible, and it is generally considered that the maximum is a maximum of 6 terminals with 24 keys. In addition, when the number of key inputs increases, the program capacity of a microcomputer such as a key scan of the output terminal increases, which puts a strain on the ROM capacity.

Further, as a conventional example, a key input method utilizing A / D input of FIG. 7 (b) is also considered. However, this method requires A / D resolution as the number of keys increases, and each voltage needs to be generated by a highly accurate resistor, which is disadvantageous in terms of cost and practicability.

The present invention solves the above-mentioned conventional drawbacks, in the key input method of the operation unit, instead of the key matrix method,
The purpose is to provide an effective key reading method.

In order to achieve the above object, the microcomputer of the control circuit device of the present invention is provided with a general input terminal and an analog / digital conversion input terminal (hereinafter abbreviated as A / D input terminal), and an operating unit. Is equipped with a keyboard, and the key portion of the keyboard is provided with a switch configuration that is directly connected to the input terminal of the microcomputer and the A / D input terminal. When the key is pressed, the same voltage is applied to each switch. The voltage is applied to the general input terminal, and the applied voltage is input to the general input terminal, and the analog voltage corresponding to each key is input to the A / D input terminal directly or through a resistor.

Operation According to the present invention, the switch is closed and each signal is input to the microcomputer according to the above-mentioned configuration, and the program processing of the microcomputer determines what the pressed key is by the input terminal and the A / D level. To increase the number of keys, press A /
By increasing the resolution in the D level program processing, it is possible to sufficiently cope with it. In addition, since the number of input terminals can be kept small and the output terminals are not used in the case of the usual number of input keys, there are no more output terminals. Can be used to expand the control range and improve specifications and performance.
Further, since the ROM capacity of the microcomputer corresponds to the A / D level resolution, it is possible to freely change the A / D level classification in the program processing and to increase the ROM capacity margin. It is a thing.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 shows an external view of the present invention. Reference numeral 1 denotes a main body of the high-frequency heating device, and a heating chamber 2 is provided in the main body 1. In the heating chamber 2, a stirrer, a turn
A table (not shown) is provided. 3 is heating chamber 2
An openable and closable door 4 provided at the opening of the operation unit 4 is an operation unit provided on the front surface of the main body 1 and is provided for the user to set a cooking sequence such as cooking output and time. Is provided with a control circuit device 5 including a microcomputer and a keyboard 6 for transmitting the user's intention to the microcomputer. Based on the input signal and information of the microcomputer 5a given from the keyboard 6, the microcomputer 5a executes the cooking sequence according to the contents already programmed and controls it.

FIG. 3 shows a circuit diagram of an embodiment of the present invention. The magnetron 7 is provided as a high-frequency oscillator, and a transformer 8 for supplying electric power to the magnetron 7 and switches 9a, 9b for opening and closing the power supply for the transformer 8 and continuing the high-frequency output of the magnetron 7 are provided.

The microcomputer 5a, normal input terminals K ₁ ~K _4, A / D input terminal A / D _1, provided with a respective terminal, the keyboard 6
Are wired corresponding to each key. The keyboard 6 is provided with keys such as a cooking output key, a cooking time key, and a start key. Each key has an independent switch function, and each switch function is input by the microcomputer 5a. Terminals (K _{1 to} K ₄ , A / D ₁ )
It is configured to open and close.

FIG. 4 shows the configuration of the switch function of the key portion of the keyboard 3. Reference numeral 10 is a panel which clearly shows the position of the key portion and which constitutes the outer appearance portion, and is designed to be easily understood by the user. Reference numeral 11 denotes a pattern sheet that constitutes contacts for a switch function. A spacer 12 is provided between the contact sheets of the spacer 12, which constitutes a contact gap between them and which is provided at a portion other than the contact of the key to ensure insulation. Has a space portion so that the pattern sheet 11 directly faces each other, and when the key portion is pressed, the contacts 13 provided on the pattern sheet 11 are touched between the upper and lower sides through the spacer 12. , The contacts are closed. Further, a reinforcing plate 14 is provided to reinforce the whole.

The operation of the above configuration will be described below.

When food is put in the heating chamber 2 and each key on the keyboard 6 of the operation unit 4 is pressed in order to set the cooking time and the output, the pattern sheet 11 of the pressed key is bent and the pattern. Contact points 13 provided on the sheet 11
However, the circuit is closed through the spacers 12. For example, if you press the Power key, the microcomputer 5
Input signals are given to the input terminal K ₁ of a and the A / D input terminal J ₁ , respectively. The key contact portion 13 of the pattern sheet 11 is connected to + 5V, and when the contact is closed, the "Hi" level is input to the input terminal K ₁ from FIG. ₁ and the other input terminals K ₂ , K ₃ and K ₄ are at “Lo” level. Next, the A / D input terminal A / D ₁ connected to the contact provided on the same key is
When the contact is closed by applying + 5V potential to the ladder circuit, the A / D level is input, and the key (Power) pressed by the level (level 1) is input.
Key). Now set the resolution of the laser circuit to 4 levels. The microcomputer 5a has input terminals K ₁ , K ₂ , K ₃ ,
It has a program process that has a matrix configuration of K ₄ and A / D input terminal A / D ₁ as shown in Table 1. By pressing a key, an input is given to each input terminal, and the key is pressed accordingly. Determine what the key is and read it. In this case, it becomes the "Power" key from FIG.

Next, a method of identifying each key will be described with reference to FIG. The resistance of the resistance values R ₁ , R ₂ , R ₃ , and R _X shown in FIG.
The following four types of A / D voltage are input to the A / D ₁ terminal.

Further, since the four common input terminal _{(K 1, K 2, K} 3, K 4) each of the four keys in are connected, so that the matrix of the table as in the fifth diagram write.

In other words, with the POWER key in the above example, input K ₁ at level 1. If it is S ₃₃ , it means that K _{3 is} input at level 3. The microcomputer 5a first determines the type of general input (K ₁ ~
K ₄ ) and then the level of A / D input to determine the type of key. Also, the POWER, S ₁₂ , S ₁₃ , and S ₁₄ keys connected to the level 1 voltage are in the preferential positions in their respective columns. For example, POWER key and S ₂₁
This is because when the keys are simultaneously input, a voltage of level 1 is generated at the A / D ₁ terminal, and the lower the level number, the higher the priority. Therefore, the priority key can be realized only by determining the matrix position, and the RO
M capacity and RAM capacity are not required.

As described above, according to the present embodiment, the number of input terminals for key scanning of the microcomputer 5a can be reduced and the A / D resolution of the A / D input can be increased as compared with the conventional key matrix system, so that the keyboard The increase in the number of keys can be easily dealt with. Further, since it is not necessary to use the output terminal of the key scan output of the microcomputer 5a, it is possible to expand the utilization and control function of the sensor and the switch.
In addition, since the output terminal of the microcomputer 5a having a margin can be secured, the degree of freedom in design is expanded in the program design of the microcomputer 5a, and as a result, the margin of the ROM capacity of the microcomputer 5a is produced.

The present invention is also advantageous for migration between patterns, which is a problem in the actual membrane structure, because a voltage is applied to the patterns only when a key is pressed. Also, A
Since the resolution of / D requires only a small resolution as shown in the embodiment, it is very advantageous in terms of accuracy in drawing a resistance pattern on an actual membrane.

Also, a second embodiment will be described with reference to FIG. In this example, the number of keys can be doubled by increasing the number of A / D input terminals by one.

That is, a similar matrix can be mounted on the other A / D input terminal, and the general input can be doubled to K ₁ and K ₂ without increase.

The key judgment table is as shown in FIG. Also, A / D
The dividing resistors R ₁ , R ₂ , R ₃ and R _X are A / D ₁ and A
The same can be applied to / D ₂ , or different values can be applied, and the feasibility in the implementation is also easy.

EFFECTS OF THE INVENTION (1) Compared with the conventional key matrix method, the number of microcomputer input terminals can be reduced, and by increasing the resolution level of the A / D input terminals, it is possible to easily cope with the increase in the number of keyboard keys. You can

(2) Since the key matrix is composed of the general input terminals and the A / D input terminals, it is possible to easily increase the number of keys only by increasing the number of terminals having a margin to increase the number of keys.

(3) Since the key matrix is composed of general input terminals and A / D input terminals, the accuracy of A / D does not need to be improved compared to the conventional key input composed of only A / D input terminals. A pattern resistor can be configured in the membrane, and it can be easily realized without increasing the cost.

(4) Compared with the conventional key matrix method, since the microcomputer output terminals are not used at all, it is possible to use these to expand the control functions such as the utilization of external devices such as sensors and switches, and expansion. It is also possible to make detailed correspondence.

(5) Compared with the conventional key matrix method, the number of extraction patterns is reduced, so the number of pins of the connector connecting the membrane and the P plate can be reduced.

(6) In the configuration of the present invention, since the voltage is applied only after the key is pressed, there is no potential difference when the key is not pressed, and therefore migration between patterns does not occur, so that the pattern design of the membrane is easy. .

(7) Compared with the conventional key matrix method, since the key scan output terminal of the microcomputer is not used at all, the program for the key scan can be omitted, and the margin of the ROM capacity of the microcomputer can be increased.

(8) Keys with high priority can be configured simply by arranging them, which can be realized without burdening the ROM of the program.

[Brief description of drawings]

FIG. 1 is a block diagram of an input device according to an embodiment of the present invention,
FIG. 2 is a perspective view of a heating device provided with the same device, FIG. 3 is a circuit diagram of the same embodiment, FIG. 4 is an exploded perspective view of the same main parts, FIG. 5 is an explanatory view of the same operation, and FIG. FIG. 7 is an explanatory diagram for comparing the same device with the input device according to the second embodiment of the present invention, and FIG. 7 is a configuration diagram showing a conventional example. 5a ... Microcomputer, 6 ... Keyboard, A / D ₁ ... Analog / digital conversion input terminals, K _{1 to} K ₄ ... General input terminals.

Claims (1)

[Claims] 1. A control circuit device comprising a microcomputer having an analog / digital conversion input terminal and a general input terminal and having a program function, and a keyboard for inputting an input signal to the microcomputer, wherein the keyboard is provided. To form an independent key contact circuit group connected to the analog / digital conversion input terminal and the general input terminal respectively, and by inputting a key of the keyboard, a direct or resistor is connected to the analog / digital conversion input terminal. The same voltage is applied to the analog / digital conversion input terminal contact and the general input terminal contact connected to the general input terminal, and the generated analog / digital conversion input terminal voltage and general input terminal are generated. By the voltage, the microcomputer is input Input device to determine the key.