A New input-filtering method for High Speed Counter module of PLC using embedded timer pulse function of general purpose MPU

범용 MPU 내장 타이머 펄스 출력을 이용한 PLC 고속 카운터 모듈의 입력 필터링 기능 개선

In this paper, A new cost-effective and accurate input noise rejection method for High Speed Counter module of PLC (Programmable Logic Controller) is proposed. By using combination of simple additional logic circuit and the Timer Pulse function of general purpose MPU, Cost-effectiveness and improvement of accuracy of filtering function can be achieved. This proposed method is verified by simulation. This proposed method is much useful for simple industrial controller based on simple microprocessor because of simplicity, accuracy and low cost.