PlC of cpu module

plc cpu modules is the control center PLC is the core of the PLC from the nerve center of the action, each PLC has at least one CPU. It functions in accordance with the procedures given PLC system receives and stores from the programmer type of user programs and data; check the power supply, memory, I / O and watchdog timer status, and diagnose user program syntax error. When the PLC into operation, the first of its way to scan each site receiving state and data input device, and are stored in the I / O image area, then one by one to read the user program from the user program memory, after the command interpreter Press the results of the implementation of the provisions of the instruction of a logical or arithmetic fed into the I / O image area or a data register. And so after all of the user program is finished, the final transfer of data I / O image area of each output state or output register to the appropriate output device, so the cycle run until it stops running.