Design And Implementation Of EtherCAT Master-Slave Station Based On FPGA

In recent years,with the development of industrial automation,the traditional fieldbus has been unable to meet the requirements of modern industry due to its bandwidth and throughput limitations.Real time Ethernet has become an indispensable technology in the field of automation with its mature characteristics.As the representative of real-time industrial Ethernet,EtherCAT(Ethernet control automation technology)is widely used in the field of industrial automation because of its fast speed,good real-time performance and flexible topology.However,at present,the realization of domestic EtherCAT master-slave station still depends on foreign special chips and technologies.The research and development of controller chips with independent intellectual property rights is of great significance to gradually get rid of foreign products and reduce application costsBased on the deep research of EtherCAT protocol,a design scheme of EtherCAT master-slave station based on FPGA is proposed.This scheme realizes a master-slave EtherCAT communication system without relying on foreign special controller chips.In order to solve the problem of how to store efficiently in the communication between EtherCAT master station and application server,memory management is introduced.Finally,based on the above work,a smoke alarm system based on EtherCAT bus technology is designed.The main research contents and innovation work include:(1)Based on the full investigation of the existing research results,this paper proposes a low-cost and independent intellectual property design scheme of EtherCAT master-slave station,which uses FPGA chip to realize the related functions of master station and slave station.Firstly,the design ideas of EtherCAT master station and EtherCAT slave station modules are described in detail,and then the functions of each module of EtherCAT master station and slave station are realized by Verilog HDL.On this basis,the hardware platform is built to verify its performance.Finally,the real-time performance of EtherCAT master-slave station is measured by oscilloscope.(2)In order to solve the problem of how to store efficiently in the high-speed communication between EtherCAT master station and application server,a design scheme of buffer memory management for industrial Internet of things based on FPGA is proposed.SDRAM memory is divided into index area and data area by using FPGA as the main controller.In high-speed communication,when the network is blocked and the data frame is temporarily stored locally,the purpose of reading and writing data by reading and writing index is realized.Finally,RTL simulation and hardware platform verify that the function of the memory management system meets the design expectations.(3)On the basis of the above work,a design scheme of smoke alarm system based on EtherCAT bus technology is proposed.The scheme includes current smoke detection sensor access,network transmission control system,alarm system and other modules.At the same time,a handshake communication protocol between FPGA and arm is proposed to solve the asynchronous clock domain problem in the communication process.First of all,the design ideas of each module are introduced in detail.Finally,a test platform is built to test the accuracy of the smoke alarm system The scheme solves the problem that the smoke detection system based on non polarity two-wire data bus is difficult to access the industrial Internet of things,and the cost of smoke detection sensor designed for the industrial Internet of things is relatively high.