Application And Research Of CAN Bus In On Board Measuring Product System

Electronic information technology achievements have been applied in agricultural machinery equipment technology in recent years, and the technic performance and operation precision of the agricultural machinery are improved. Centralized monitoring and decentralized control play an important role in agricultural machinery system. To exchange information between relatively independent ECU (Electronic Control Unit) and central controller and the display unit, the communication network must be stable and reliable. Integration of control and management of the agricultural machinery work process can be realized by exchanging information between the agricultural machineries and their parts through the communication network.CAN (Control Area Network) is a field bus technology, and it is widely used in small mobile equipment, industry control and automotive electronics industry. Its application in agricultural machinery is becoming mature. CAN bus has the function of priority and arbitration. It also has better performance in reliability and real-time. The application of CAN to modem agricultural machinery is analyzed in this paper. According to the shortcoming that traditional communication way in domestic agricultural machinery has poor reliability, wiring complex and big volume, CAN bus network of onboard measuring product system is designed.In view of the CAN application in other industry and measuring product system of the combine harvester, this paper discusses the technical specification, communication principle and design procedure of the CAN bus, and achieve the development process of CAN bus network. The hardware circuit and software program of communication network base on CAN bus is designed in this paper.On the basis of studying the international open higher layer protocol and user-defined protocol, application layer protocol of CAN bus is defined. The communication system is debugged, and its function test is carried out. Qualitative analysis of the CAN bus network real time is conducted.