JPH09270685A - Operation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute lots of operations with a few operation keys. SOLUTION: A reference voltage Vref is given to an input terminal of a 1-chip microcomputer having an A/D converter function via a resistor R5. Plural series connection resistors R1-R4 are connected between the input terminal and ground and switches SW1-SW4 closed through key operation are provided in parallel with the plural series connection resistors R1-R4. Keys operated multiply are discriminated by comparing the input voltage resulting from combinations of plural switches with a content of a table representing a data range. A control output is outputted from the result of discrimination and lots of different operation commands are made.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to discrimination of operated keys among a plurality of keys such as operation keys.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, a circuit for recognizing a key having an AD conversion function has one end of a plurality of key switches SW1 to SWn (n = 4 in FIG. 3) of an operating section 3'grounded. The other end is connected in series to the connection point of the resistors R1 to Rn.

A reference input voltage Vref is supplied to a connection point between the resistor Rn and the key switch SWn via a resistor Rn + 1 and is input to an AD converter 2 provided at the input of the one-chip microcomputer. The value converted by the AD converter 2 is processed by the one-chip microcomputer 1, and which of the key switches SW1 to SWn is operated is compared with the value stored in the memory in advance to be discriminated and the key switch is operated. The operation is controlled according to the command issued.

[0004]

When the conventional key switch is operated in multiple, it is recognized that the key switch closest to the AD input side is operated because one end of the key switch is commonly grounded, and the multiple operation is performed. I couldn't order. An object of the present invention is to issue various operation commands with a small number of key switches.

[0005]

According to the present invention, reference voltage supply means for supplying a reference input voltage of an AD converter and a plurality of resistors (Rn-1) via the resistor (Rn + 1) from the reference voltage are provided. Connected in series and connected between input terminals of the AD converter, connected in parallel to each of the plurality of resistors (R1 to n) and connected or disconnected by operating means, and operated by the operating means. Further, the operating device comprises a discriminating means for detecting and discriminating a voltage value due to the contact or disconnection of the switch means, and means for performing control output according to the operation of the operating means by the discrimination of the discriminating means.

Further, in the present invention, when the impedance values of the resistors R1 to n are r1 to rn, r1 <r2, r1 + r2 <r.
3, ..., r1 + r2 + ... + rn <rn + 1. The present invention is an operating device capable of issuing various types of operation commands with a small number of operating means, because the operated combined voltage value can be stored and discriminated in advance even when a plurality of operating means are operated multiple times.

[0007]

Embodiments of the present invention will be described. FIG. 1 is a circuit diagram showing one embodiment of the present invention. The operating device of the present invention has a one-chip microcomputer 1 and issues commands for controlling the device.

The AD converter 2 is connected to the input of the one-chip microcomputer 1.
With 8 bits or 16
Bit digital data is temporarily stored in the memory and compared with the threshold value C of a table stored in advance in the one-chip microcomputer 1 to determine what the command by the key input of the operation unit 3 is.

The 1-chip microcomputer 1 uses V as a reference voltage.
ref is supplied. Further, the reference voltage Vref is connected to the input terminal of the AD converter 2 provided in the one-chip microcomputer 1 through the resistor R5, and further, a plurality of resistors R1, R2, R3, R4.
Are connected in series and are connected between the input end and ground.

A plurality of resistors R1 to R4 are connected to switches SW1 to SW1.
SW4 is connected in parallel, and the resistors R1 to R4 are short-circuited by the switches SW1 to SW4 by a key input operation. The resistance value of resistors R1 to R5 is r1
When r5 is set to r5, the input voltage V to the AD converter 2 is V when the switches SW1 to SW4 are short-circuited independently and when a plurality of switches are short-circuited (simultaneous multiple pressing) to short-circuit a plurality of switches. = A · Vref / (1 + A) However, A = (r1 + r2 + r3 + r4-B) / r5B is represented by the sum of the short-circuited resistance values.

The resistance values are r1 <r2, r1 + r2 <r3, ...
.., r1 + r2 + r3 + r4 <r5, r1
And r2 switches SW1 and SW2 are short-circuited, the key resistance is between r2 and r3.
3 and r1 or r2 are operated by multiple keys and switch SW3
When SW1 and SW1 or SW2 are short-circuited, the resistance value is r3
Between r4 and r4, as well as r4 and r1 or r2 or r3
When the multiple key operation is performed by the above, each resistance value is determined so that the resistance value becomes a value between r5 and r4, all the multiple short circuit states are made different, and the threshold value C is stored in advance in the memory of the one-chip microcomputer 1. The table is stored and it can be discriminated by comparing with the threshold value C. When the input voltage is AD-converted by the reference input voltage Vref, the threshold value C is the voltage in the state of each operation command so that it is possible to surely determine the input voltage value when a plurality of switches are simultaneously pressed by multiple operations. A value approximately in the middle of the values is stored in advance in the memory as a data table to reduce the probability of malfunction due to variations in the reference voltage, variations in resistance, and the like.

R1 = r, R2 = 2r, R3 = 4r, R4 = 8
The multiple key operation command when r and R5 = 16r will be described with reference to the flowchart shown in FIG. When the keys of the key operation unit 3 are operated and the switches SW1 and SW4 are short-circuited at the same time, the voltage V1-4 at the input end of the AD converter 2
Is V1-4 = (R2 + R3) Vref / (R2 + R3 + R5) = 3Vr
ef / 11, and the voltage V0 when no key is operated is V0 = (R1 + R2 + R3 + R4) Vref / (R1 + R2 + R3 + R)
4 + R5) = 15Vref / 31, and the one-chip microcomputer 1 detects that the voltage has fluctuated and determines that the key operation has been performed (S1).

When the key is operated in S1, the data converted into digital data by the AD converter 2 is temporarily stored in the memory (S2). The threshold values C of the table stored in advance in the memory are compared from the largest value, and the range of the threshold value C to which the data temporarily stored in S2 is included depends on whether the threshold value C is smaller than the threshold value C (S3). To determine.

According to the threshold value C of the table, for example, the switch S
W1 was operated alone or switches SW1 and S
It is determined that W4 is short-circuited and the command state when a plurality of operation keys are operated is detected (S4).

The operation keys detect that SW1 and SW4 are simultaneously short-circuited, and the one-chip microcomputer 1 outputs a control output according to the operation keys to control the apparatus (S5).

Similarly, even when the operation key is operated independently, it is possible to determine which switch is short-circuited by comparing the data digitally converted by the AD converter 2 with the threshold value C stored as a table. Can be done, AD
The converter 2 converts it into a high-precision digital value, and even when multiple operation keys are operated, it is possible to accurately determine which key has been operated, so that complex command operations can be performed with a small number of operation keys. It is possible to provide a device that can. Further, in the description of FIG. 2, the case where the comparison is performed from the larger value of the threshold value of the table has been described, but the same determination can be made when the comparison is performed from the smaller value to the greater threshold value.

[0017]

According to the present invention, since multiple operations of the operating section are accurately discriminated, it is possible to execute various commands with a small number of operating sections.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of an operating device according to the present invention.

FIG. 2 is a flowchart illustrating an example of the operation of the present invention.

FIG. 3 is a circuit diagram showing a conventional example.

[Explanation of symbols]

 1 1-chip microcomputer 2 AD converter 3 Operation unit

Claims (2)

[Claims] 1. A reference voltage supply means for supplying a reference input voltage to an AD converter, and a plurality of resistors (R n to 1) connected in series from the reference voltage via a resistor (R n + 1). Switch means connected between the input ends of the switch and connected in parallel to each of the plurality of resistors (R1 to n) and connected or disconnected by the operation means, and connection or disconnection of the switch means operated by the operation means. An operating device comprising: a discriminating means for detecting and discriminating a voltage value by the discriminating means, and means for performing a control output according to the operation of the operating means by the discrimination by the discriminating means. 2. The impedance value of the resistors R1 to n is r1 to
When rn, r1 <r2, r1 + r2 <r3, ..., r1
2. The method according to claim 1, wherein + r2 + ... + rn <rn + 1.
The operating device as described.