Research On The Implementation Of CANopen DS402 Protocol In Motion Controller

The CANopen DS402 protocol which is a CAN-based protocol is designed for motion control systems.In foreign countries,the CANopen DS402 protocol has been applied to real-time Ethernet protocols and is widely used in many industries.In recent years,the CANopen protocol has been studied gradually in China.However,CANopen DS402 protocol itself is relatively complex,and major manufacturers have modified the protocol to some extent in order to protect their own interests,which has made the research of the protocol more difficult.At present,domestic universities and colleges are still in the study of the protocol itself and CANopen equipments independently developed in industry are scarce and expensive.Therefore,according to the CIA standard,this paper studies the implementation of CANopen DS402 protocol based on STM32F407,and successfully exchanges data with the motion controller.The specific work of this paper is as follows:Firstly,the implementation process of CANopen DS402 protocol is emphatically studied.Also the message syntax of process data object(PDO),service data object(SDO),network management object(NMT),emergency and synchronous message service is analyzed,laying a foundation for the software implementation of CANopen DS402 protocol.Secondly,in order to construct the CANopen DS402 protocol that conforms to the CIA standard,this paper takes STM32F407 as the protocol carrier and designs the circuit of CAN port and serial port on the hardware;on software,according to the idea of modularization,the software development of the object dictionary,SDO,PDO,NMT,sub-protocol state machine and other modules in the protocol is carried out,and the functions of synchronous and asynchronous transmission of PDO,the access of SDO to object dictionary,state machine management of NMT and switch of sub-protocol state machine are completed.Then,in order to solve the problems caused by debugging CAN analyzer,such as large amount of data and difficulty in analysis,a debugging system based on serial communication is developed by using idle serial port resources in this paper,which realizes the functions of protocol stack status display,human-computer interaction interface and reading and writing the object dictionary.By using this debugging system,the debugging between communication interface and object dictionary,application program and object dictionary in the protocol has been completed.Finally,in order to solve the problems of low usability and complicated configuration caused by using USB-CAN card as analog master station,a motion control system based on PILZ motion control card is built.It also realizes the barrier-free data exchange between CANopen interface and the motion control card,and the position and speed operation mode in motor control,achieving the expected effect and provided research experience and experimental method for the research and development of independent equipment.