Development Of Car Body Controller With CAN Bus Communication (Based On SAEJ1939 Protocol) JH476

With the rapid development of the modern automobile industry,the increasing of automobile electronic control unit and electronic device,using the traditional wire harness for point-to-point connection has been far unable to meet this demand,in this situation,using CAN bus as the representative of the vehicle bus came into being,car body controller based on CAN bus technology not only meets the the functional requirements of vehicle control,the cost can be reduced effectively,simplify the redundant wiring harness,brought a qualitative leap to optimize the control of the car.This paper first to the domestic and foreign body control system development makes a brief introduction to the volume,analyzes the advantages and disadvantages of the vehicle body controller of centralized and distributed,and the development trend of domestic and foreign body controller of the corresponding instructions.And then starting from the CAN bus,the hierarchical structure of CAN bus for the corresponding description with the schematic drawing,the form of the four frame types of CAN bus and the frame are described in detail.The SAEJ1939 protocol defined in each layer and message format,message identifier allocation,data definition frame in detail and the communication process and communication process of analogy,then according to the functions of the technical specification of customers for sorting out the functional requirements of the vehicle body controller modules,such as power supply,input and output,MOSFET driver module,circuit design of each module is explained,and the effect of some of the important components in the circuit are described in detail.In the aspect of software design of system software design scheme for the corresponding description in the CAN bus communication of each layer of CAN bus and relevant specifications,software process,node initialization,message sending and receiving a message of explanation and description.The vehicle body controller designed experiment and a series of tests,to appear in the real car test in the right turn signal frequency in detail,and finally find the problem and solve the problem.This paper based on SAEJ1939 protocol of CAN bus in the body of the controller hardware circuit and software driver module is detailed expounded,in the real vehicle tests show problems for the future development of similar products have a very good reference,through a series of tests verify the final developed body controller completely meet the functional requirements of customers,to prove the feasibility of the system.It is hoped that these efforts will provide some value to the independent development of the CAN bus control system and the body control system of relevant automobile electronics manufacturers in the future.