Design And Implementation Of Pulse Width Modulation PLC Slave Station Based On EtherCAT Protocol

PLCs have evolved from the very first relay control to today's fully functional embedded control systems.The PLC can perform excellent control tasks such as sequential logic control,process control,and motion control.Because of its complete functions,short communication cycle,high reliability,high safety,and high degree of modularity,PLC is currently being widely used in power electronics,energy manufacturing,environmental protection,machinery manufacturing,and medical equipment,food manufacturing,and industrial control.And other civil industries as well as aerospace,armament and other defense industry.The PLC combined with the high-speed fieldbus is the basis for achieving "Industry 4.0".While PLC is so important,90% of the domestic PLC market is occupied by foreign products.Therefore,whether it is to guarantee the security of national defense,or to achieve the "Industry 4.0" to complete the smart production and all things connected,we need a series of high-speed,high-efficiency,self-controllable PLC.The main work of this article includes the following points:(1)In combination with the requirements,the hardware composition of the slave station is given.The domestic CPU(BM3107)was selected as the microprocessor,the ET1200 chip as the slave station microcontroller,and other devices compose the slave hardware(2)The overall architecture of the slave station was designed based on the requirements and the hardware resources and the Ether CAT protocol.The software is divided into the driver layer,application layer and control layer.And implement the code.(3)Based on the rules of writing traditional ESI files,some rules were modified and new rules added.The new ESI file makes the user's operation simple and efficient in the case of transmitting large amounts of data,and also improves the data transmission efficiency.(4)After completing the hardware and software,the slave station has undergone rigorous testing.The test results show that the design and implementation of pulse width modulated PLC slaves completes the initial design requirements.