Research On CAN Bus System Based On FIFO And Priority Sequence

In the modern automotive electronics technology,CAN bus is the most important serial communication bus.Because of reliability,real-time,interoperability,flexibility,economy and other characteristics,CAN bus are widely used in communication and control system of various automotive electronic components.CAN bus communication is a communication system based on priority arbitration and scheduling.Therefore,the study of scheduling based on CAN bus is of great significance to improve the utilization of CAN bus and the communication performance of the system.This paper mainly studies CAN bus system based on FIFO and priority sequence,an idea of model optimization is proposed,and the specific research content is divided into the following parts:(1)Study based on FIFO and priority sequence of CAN bus network system schedulability analysis algorithm.For the two models,the transmission characteristics of messages are analyzed to calculate the worst-case response time.The minimum bus rate and maximum bus utilization that the system can schedule are discussed,and the performance of the system is studied through the bus utilization.(2)Study the optimal priority allocation algorithm and assign appropriate priority to messages of different sequences.By reducing the influence of priority inversion caused by FIFO sequence,the bus utilization can be improved under the condition that the sy stem is schedulable.(3)The experimental results show that the schedulability analysis of the two models is consistent with the experimental results,and the node queuing sequence has different effects on the system performance of the two models.Optimal priority allocation algorithm can ensure that CAN bus network is schedulable and improve bus utilization.The factors that affect system performance include the number of buffers,the number of FIFO sequence nodes,the priority of node messages,the number of node messages and the number of nodes.Through theoretical analysis and experimental verification,the study of schedulability algorithm and optimal priority allocation algorithm provides a theoretical basis for improving bus utilization.The experimental results verify the validity of the theoretical analysis.The research of this subject is of great significance to the further development of CAN bus.