Method for transmitting and receiving data between mpu and memory in plc

Abstract

A method for transmitting and receiving data between an MPU and a memory operating in mutually different operating voltages in PLC is proposed, the method including: outputting, by the MPU, a CS (Chip Select) signal and an address signal in order to read data by approaching to the memory; outputting, by an OR gate, an activation signal for activating a data input buffer by receiving the CS signal and the address signal; outputting, by an access signal output buffer, a memory access signal for operation of the memory by receiving the CS signal and the address signal; outputting, by the memory, data requested by the MPU to the data input buffer by responding to the memory access signal; and outputting, by the data input buffer, the received data to the MPU by receiving the data outputted by the memory.

Dependencies are inferred from the claim text.