JPH0540556A - Key switch controller - Google Patents

Abstract

PURPOSE:To facilitate control by generating a control signal from a clock signal to select each switch group from a key switch group. CONSTITUTION:A count part 2 inputs a clock signal 1, executes clock counting and outputs the counted data to an information conversion part 4. The information conversion part 4 decodes the counted data and transmits a signal to an output driving device 5 for key switch control so as to always select one switch group from the plural switch groups with time division, and this driving device 5 outputs the control signal to a key switch group 13. The key switch group 13 transfers the ON/OFF information of each key switch to an input device 7 for key switch control. The input device 7 for key switch control transfers this information through an information transmitting output 12 to a CPU.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a key switch control device, and more particularly to a control method of an output drive device for key switch control.

[0002]

2. Description of the Related Art A conventional key switch controller is a central processing unit (hereinafter referred to as "center processing").
The key switch is connected to each input / output device, and the key switch control is such that the CPU executes the program data held in the memory so that a specific switch having a periodicity is output from the output device. The control code is output to a plurality of key switches, and the plurality of key switches are realized by transmitting the ON-OFF state of each key switch to an input device.

[0003]

However, in the prior art, in order to obtain the information of the key switch, the CPU occupies most of its information processing ability for the key switch control, and therefore, for the key switch control. Main CP in addition to CPU
A system configuration in which U performs information processing was adopted and it was expensive in price. Further, when the information processing and the key / switch control are performed by one CPU, the information processing takes a long time, or the programs for the information processing and the key / switch control become complicated, resulting in an adverse effect on the memory capacity.

Therefore, an object of the present invention is to provide a control device capable of key switch control with a simple circuit configuration in order to solve the above-mentioned conventional problems.

[0005]

In order to solve the above-mentioned problems, a key switch control device of the present invention has a plurality of key switch inputs to the output terminals of a plurality of key switch control output drive devices. Keys in which the terminals are respectively connected and the output terminals of each key switch are connected to the input terminals of a plurality of key switch control input devices.
In a switch control device, a counting unit that inputs a clock signal and measures the clock signal, an information conversion unit that inputs count information of the counting unit and converts measurement information, and the converted information from the information conversion unit by the key. -It is characterized by having an electric transmission path for transmitting to the input terminal of the switch control output drive device.

[0006]

As described above, the data of the information conversion unit (hereinafter referred to as a "decoder") for converting the data of the counting unit (hereinafter referred to as a "counter") for inputting the clock signal and measuring the clock signal is output-driven for key switch control. Outputting to the output terminal of the device, driving a plurality of key switches at the output terminal, and taking in ON-OFF state data from the output terminal of the key switch from the input terminal of the key switch control input drive device. With this, key switches can be controlled independently of CPU control.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration and embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a key switch control device of the present invention. The counting unit 2 inputs the clock signal 1 and performs clock counting, and outputs the count data to the information converting unit 4. The information conversion unit 4 decodes the count data, and sends a signal for selecting one switch group from a plurality of switch groups in a time division manner to the key switch control output drive unit 5 and the drive unit. Reference numeral 5 outputs a control signal to the key switch group 13. The key switch group 13 transfers ON / OFF information of each key switch to the key switch control input device 7. The key switch control input device 7 is a CPU via an information transmission output 12.
To transfer the information to.

FIG. 2 shows an embodiment of the circuit configuration of the counting section and the information converting section. This circuit uses a 3-bit synchronous counter to count CL, that is, the clock signal 1, and the outputs Q0, Q1, Q2 of the data input type flip-flop 14 are periodically changed by the rising edge of CL. .. Q0, Q1 and Q2 have eight output states,
It can be expressed, and the state is converted into eight output signals 6 (OUT0 to OUT7) corresponding to each state in the information conversion unit 4. The output signal is the output device 5 for controlling the key switch.
The key switch group 13 is controlled.

In FIG. 5, CL, Q0 to Q2, OUT0 to OU
The timing diagram of T7 is shown. Of the output signals 6 (OUT0 to OUT7) from the information conversion unit 4, only one output signal is at the LOW level for a certain period of time, and only the switch group connected to the signal line is operable for the certain period. Figure 3
Is an embodiment of the key switch group 13. The output signal 6 is connected to the anode terminal of the diode, and LOW is output to the cathode terminal only when the output signal 6 is LOW.
When the level is propagated and the output signal 6 is at the HIGH level, the cathode terminal is in the open state (state in which the potential is not fixed)
Becomes The input terminals of a plurality of key switches are connected to the cathode terminal, and each output signal 6 is divided into eight switch groups, so one of the switch groups is always selected periodically. Will be done.
Focusing on the switch group selected for OUT0, the input terminal of the key switch is L during the selection period.
The OW potential is applied. At this time, if a certain key switch is in the ON state, LOW appears at the output terminal of the key switch, and in the OFF state, the open state appears. Also, during the non-selection period, the key switch O
The open state appears regardless of the N / OFF state. Different switches for output terminals IN0-INn
One switch output terminal of each group is connected, and the switch status of each switch group is time-divisionally output. FIG. 4 shows an embodiment of an input device for controlling a key switch. The output terminals IN0 to INn from the key switch group 13 are connected to the key switch information input terminal 15 to store the key switch information in the data holding circuit 10.
Can be taken into. To capture data, output terminals IN0 to IN from the key switch group 13
Since the output state of n is two states of open and LOW level, it can be taken in by the data holding circuit 10.
Since it is necessary to convert to the H / LOW state, the input pull-up circuit 9 is provided, and 16 is a pull-up resistor for converting the open state to the HIGH state. The latch clock 17 (LC) is input so that the data can be fetched within each of the eight selection periods. Key via the data latch output terminal 12
The switch information is transferred to the CPU, for example. OU in Figure 6
The timing diagram of T0-OUT7, IN0-INn, LC is shown.

[0010]

As described above, the key switch control device of the present invention generates the control signal for selecting each switch group in the key switch group 13 from the clock signal, and therefore, the key switch information. The system or CPU requesting the request is released from the work of outputting the control signal, and only the work of obtaining the key switch information is required.

[Brief description of drawings]

FIG. 1 is a block diagram of a key switch control device of the present invention.

FIG. 2 is a circuit diagram of an embodiment of a counting unit and an information converting unit according to the present invention.

FIG. 3 is a circuit diagram of an embodiment of a key switch unit of the present invention.

FIG. 4 is a circuit diagram of an embodiment of an input device for controlling a key switch of the present invention.

FIG. 5 is a timing diagram of a counting unit and an information converting unit according to the present invention.

FIG. 6 is a timing diagram of the information conversion unit and the key switch control input device of the present invention.

[Explanation of symbols]

1 clock signal 2 counting unit 3 counting information transmission signal 4 information conversion unit 5 key switch control output drive device 6 key switch control output signal 7 key switch control input device 9 key switch control input device Pull-up circuit 10 Data holding circuit in input device for key switch control 12 Data latch output terminal 13 Key switch section 17 Key switch information capture signal

Claims (1)

[Claims] 1. The input terminals of a plurality of key switches are respectively connected to the output terminals of a plurality of output switches for controlling a key switch, and the output terminals of each key switch are for controlling a plurality of key switches. In the key switch controller connected to the input terminal of the input device, a counting unit for inputting a clock signal and measuring the clock signal,
An information conversion unit for inputting count information of the counting unit and converting measurement information, and a transmission path for transmitting the converted information from the information conversion unit to an input terminal of the key switch control output drive device. Key switch control device.