FPGA Design And Implementation Of Multi-device Data Acquisition System Based On Optimized EtherCAT Protocol

Measurement and control technology is widely used in many fields such as modern science and technology,industrial production and national defense technology It is an important indicator to measure the modernization of science,industry and national defense in a country.As the primary and important park in measurement and control technology,data acquisition plays an important role in the development of national science and technology and industry.The traditional data acquisition system has a low communication rate and is difficult to be compatible with the network,it has been unable to meet the requirements of modern industrial development.Applying Industrial Ethernet to data acquisition systems is the best solution for data acquisition systems.In recent years,the EtherCAT protocol has been widely used in industrial Ethernet due to its high real-time performance and high data transmission rate.This paper optimizes the existing EtherCAT protocol,designs a simplified real-time industrial Ethernet protocol,and based on this protocol,completes the FPGA design and implementation of a multi-device data acquisition system.The system adopts the master-slave working mode,and it can realize the EtherCAT communication of one master and nine slaves.The functions of the EtherCAT master and slave are fully implemented on the FPGA,breaking through the existing EtherCAT master requires the use of a standard Ethernet controller,and the slave uses the limitations of the dedicated ESC slave communication control chip.Secondly,the master-slave protocol switching of EtherCAT is realized,and the functions of the master station and the slave station are unified on one device.The master or slave function that the device can perform can be selected according to the needs of use,breaking through the limitations of existing EtherCAT device masters and slaves with a single function on the hardware.At the same time,based on the above optimized EtherCAT protocol,a multi-device data acquisition system is designed.This system not only has the advantages of high speed and high synchronism of parallel bus data acquisition system,but also has a simple and convenient serial bus data acquisition system and low cost.The advantages of the data acquisition system are greatly improved,and the synchronization accuracy of less than 100 ns is achieved.The whole system and protocol are completely implemented on FPGA,it is simple and reliable,and the system has high integration and high flexibility,which can be compatible with other embedded networks.The whole system is designed in VHDL language on Altera's QUARTUS ?software,and the simulation is verified by ModelSim software.Finally,the system test platform is built and the function of the system is tested and verified.The experimental results show that the design of this paper can realize the communication function of EtherCAT master station and slave station of a master multi-slave system and the function of data acquisition system based on optimized EtherCAT protocol.