Design of Modbus-RTU master station gateway based on EtherCAT bus
EtherCAT is widely used in the field of industrial control in China,and many industry fields use it as the control system bus.Modbus is also a standard and open communication protocol,many instruments,sensors,and frequency converters support the Modbus protocol,as Modbus slave device is widely used in industrial control sites.In order to solve the communication prob-lem between EtherCAT bus and Modbus equipment in industrial control field,a Modbus-RTU master station gateway module based on EtherCAT bus is designed,which realizes the conversion between EtherCAT bus and Modbus protocol.The design supports two RJ45 interfaces and one DB9 interface,the RJ45 interface supports the EtherCAT interface protocol,and the DB9 interface sup-ports the Modbus-RTU main protocol.The design can be configured with chain and ring topologies structure through two RJ45 in-terfaces,so it can be flexibly applied in EtherCAT networks.