Implementation Study Of EtherCAT Master On Embedded Platform

The rapid development of the intelligent manufacturing industry proposes higher demands on the real-time,reliability,and communication bandwidth between nodes.As one of the most basic core technologies in smart manufacturing,industrial field communication technology has always been in rapid development.In recent years,a large number of outstanding industrial field bus standards have emerged.Among them,Beckhoff's industrial Ethernet technology standard stands out due to its advantages such as simple networking,low cost,and real-time reliability.The industrial Ethernet master station can operate on multiple platforms,requiring only a standard network port to be provided by the hardware.Therefore,a low-cost,simple,flexible,high-speed,real-time embedded platform can be used as an industrial Ethernet master station in hardware.Thus,the embedded platform and EtherCAT provide a new network,information,and intelligent solution.This thesis studies the EtherCAT protocol,and analyzes the application of EtherCAT in each platform.Aiming at the longer and unstable frame cycle of the EtherCAT master on the Windows platform,the STM32F767,an ARM based Cortex-M7 MCU was proposed to implement the EtherCAT master.Firstly,the RT-LAB open source Ether CAT master SOEM1.3.1(Simple Open EtherCAT Master)software architecture was analyzed;Secondly,the STM32F767 Ethernet device driver was optimized and the dependency on the OS was discarded,SOEM was ported to STM32F767 platform;Finally,by adopting 500 us interpolation cycle,using two Sanyo R series servo drivers and servo motors as EtherCAT slaves,tested two servo axes position control in CSP mode,verified the effectiveness of the implementation of the EtherCAT master on embedded platform.The experimental results show that the frame cycle of the process data on the embedded platform is stable at 68 us ± 1us compared with the non-real-time platform of 150-2000 us and real-time Linux platform of 70 us in the fastest speed with 10 us deviation.It is proven that the ARM platform at 216 MHz is fully capable for using as an EtherCAT master with real-time performance at 100 us or below,providing a more simple and lightweight EtherCAT industrial solution for industrial automation,Internet of things and other fields.