Bassed On The Automobile Node Point Promotion’s Designing And Reasearching Of CAN Bus

Modern cars are more and more intelligent as the development of automobileindustry.Much more electronic equipments are used in the motors. Meanwhile, it aslobrings some problems, increasing the amount of electricity wire and the automobile’scircuit complexity, decreasing the reliability, increasing the difficulty of maintenance.To solve this kind of problem and improve communication in real time, the CAN buspriority promotion ideas are applied to the vehicle control networkIn this paper,situation of study about CAN bus at home and abroad isanalysed.CAN protocol’s instantaneity are studyed on the basis of fully learning aboutbasic theory of CAN bus. It can valuably improving system’s instantaneity by takingreasonable measures to overcome the defects of fixed priorityFirst, the defects of CAN bus real time and the reasons were analysed. A prioritypromotion algorithm was proposed and the mathematical model and implementationswere given.Second, CAN bus communication experiment system was constructed onthe idea of modular design.Five CAN nodes formed the system were the dataacquisition module,window control module,display module,lamp control module andmain node module.The hardware circuit and software realization were given in theexperiment system.The simulation model of CAN communication protocol wasestablished in Matlab/Simulink/Stateflow by applying the strong function of Matlab.Anew way is provided for CAN net reserch.The correctness of the hardware circuit is verified though the whole systemcommissioning.As expected,using the single chip processor as the microprocessor ofthe CAN bus multi node communication is realized.