JPH02307775A - Operating switch control circuit of printer - Google Patents

Abstract

PURPOSE:To reduce the number of control signal lines controlled by a microcomputer by connecting switches in parallel or in series to an analog port input terminal equipped with a microprocessor and monitoring the state of switches using a 1 to 2-bit analog port. CONSTITUTION:A control panel circuit 2 consists of resistors 2g to 2l and operat ing switches 2a to 2l, and a voltage divided by each half of the total resistors, for example, the resistor 3a and resistors 2g to 2i connected in parallel using a power supply voltage connected to a terminal A, generates at a terminal K, and a voltage divided by the resistor 3b and resistors 2j to 2l generates at a terminal K. If this voltage value is entered from analog ports AN1, AN2 on microcomputer of a control circuit 1, the ON/OFF state of the operating switches 2a to 2c, 2d to 2f can be determined using the analog/digital conversion function of the microcomputer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printer operation switch control circuit, and more particularly to a printer operation switch control circuit for managing a plurality of switches on an operation panel.

[Conventional technology]

Conventionally, an operation switch control circuit for this type of printer has been configured to include operation switches 2a to 2 of an operation panel circuit 2, as shown in FIG.
The same number of control signals as f are input through the input port of the microprocessor of the control circuit 1, and the operation switches 2a to 2a are input.
2f or, as shown in FIG. By performing parallel-to-serial conversion, the control signals are reduced to several bits.

[Problem to be solved by the invention]

The conventional printer operation switch control circuit described above has a simple circuit in the example shown in FIG. Therefore, it is necessary to add a human output port circuit, or the number of signal line cables from the operation panel increases, which has the disadvantage that the cables and connecting connectors become expensive. In addition, in the example shown in Figure 3, although the number of connection signals is reduced, the circuit becomes more complex and the control program for the microprocessor also becomes more complex, resulting in an increase in the cost of the circuit and an increase in the capacity of the control program. There is a drawback that it can be done.

SUMMARY OF THE INVENTION An object of the present invention is to provide a printer operation switch control circuit that can reduce the number of control signal lines controlled by such a microcomputer, simplify the circuit, and realize it at low cost.

[Means to solve the problem]

The operation switch control circuit for a printer of the present invention includes a plurality of switches provided on the operation panel and a plurality of switches provided on the operation panel. and a control circuit centered on a microprocessor that inputs the state of the switches and sets various functions and controls operations based on the state, and connects the plurality of switches in parallel or in parallel to the analog port input provided in the microprocessor. It is configured to connect in series and monitor the status of multiple switches using a 1- to 2-bit analog port.

〔Example〕

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

FIG. 1 shows an operation switch control circuit for a printer showing an embodiment of the present invention.

As shown in FIG. 1, this embodiment includes means for connecting a plurality of switches 2a to 2f in a control panel circuit 2 in parallel or series, and a voltage dividing resistor 3 for dividing the power supply voltage supplied from a terminal A. a, 3 b and 2g to 21, and has analog-to-digital conversion function, analog port input A
N1. The control circuit 1 includes a microprocessor having an AN2.

That is, the operation panel circuit 2 is composed of resistors 2g to 21 and operation switches 2a to 2f, half of each of which are connected in parallel, and the power supply voltage supplied to terminal A is divided by the resistors 3a and 2g to 21. A voltage is generated at terminal J, and a voltage divided by resistor 3b and resistors 2J to 21 is generated at terminal K. This voltage value is applied to the analog port AN1 of the microcomputer of the control circuit 1. When input from AN2, the analog-to-digital conversion function of this microcomputer converts the operation switches 2a to 2C and 2d.
~2 f(7) The state of ONloFF can be identified.

Although the circuit of this embodiment is composed of six operating switches and half of them are connected in parallel, the number of operating switches and the number of circuits connected in parallel are arbitrary. These are determined by the resolution of the analog-to-digital conversion capability of the microcomputer.

〔Effect of the invention〕

As explained above, the printer operation switch control circuit of the present invention connects operation switches in parallel or series,
The voltage division ratio is changed by changing the resistance value connected by the 0N10F'F of the operation switch, and the voltage value is converted into a voltage value registered in advance in the microcomputer by the analog-to-digital conversion function of the microcomputer.The relationship between the voltage value and the operation switch is shown below. By constantly monitoring the state of the operation switch from the table, the number of control signal lines controlled by the microcomputer can be reduced, additional circuitry is unnecessary, and the system can be realized at low cost.

[Brief explanation of drawings]

FIG. 1 is a printer operation switch control circuit diagram showing one embodiment of the present invention, and FIGS. 2 and 3 are printer operation switch control circuit diagrams showing one conventional example and another example, respectively. 1... Control circuit (microcomputer), 2
......Operation panel circuit, 2a-2f...Operation switch, 2g-21...Resistor, 3a,
3 b...Resistor, A...Power voltage supply terminal, J, K...Analog input terminal, H...
...Ground terminal.

Claims (1)

[Claims] In an operation switch control circuit of a printer having an operation panel for setting and controlling various states when printing on a recording medium, a plurality of switches provided on the operation panel and the states of the plurality of switches are inputted and the states thereof It has a control circuit centered on a microprocessor that sets various functions and controls operations, and the plurality of switches are connected in parallel or in series to an analog port input provided in the microprocessor, and a 1- to 2-bit control circuit is provided. A printer operation switch control circuit characterized by monitoring the states of multiple switches using an analog port.