Keyboard processing system

Abstract

Abstract PURPOSE: To make a complicated logical circuit unnecessary and simplify the equipment, by scanning the matrix by simple hardware, and executing the code conversion of the key code which has been read by scanning the matrix, by means of the firmware processing of the processor. CONSTITUTION: The respective key switches constituting the key matrix 1 are made to have the prescribed key codes, respectively, the decoder 2 is controlled by the counting value of the prescribed bit from the oscillating circuit 8 of the counter 3, and the input lines #0W#7 in the line direction of the matrix 1 are scanned in order. Also, the selector 4 for selecting the output of the output signal lines #0W#7 of the matrix 1 is selectively scanned by the counting value of the counter 5, and the keyboard status is provided to the processor 6 and the inhibiting gate 7. Also, the counting value of the counters 3, 5 is provided to the A register as a key code, the code conversion of the key code is executed in accordance with the keyboard processing routine of the storage device, by the processor, and the device can be simplified. COPYRIGHT: (C)1981,JPO&Japio

Inventors

• 👤 Takatoshi Ishii
• 👤 Takahisa Nakano
• 👤 Tamaki Hayama

Bibliographic Details