Abstract:

For the scheduling algorithm applied in CAN FD network, when the earliest deadline algorithm of average partition coding method performs non-preemptively scheduling on messages, it will have the problems of limited encoding ability for a large range of deadlines, high probability of priority reversal of messages and high bus load. By analyzing various causes that cause of message transmission delay and combining with the shortcomings of previous partition scheduling algorithms, this study proposes an improved method of message scheduling based on the earliest deadline first algorithm based on exponential-power function partition, that is, on the basis of exponential partition of message deadline, power function partition subdivision is further adopted. In this study, the schedulability of the algorithm is analyzed and verified by simulation using CANoe. Experiments show that compared with the existing average partition scheduling algorithm, the improved algorithm expands the representation range of deadline, reduces bus load, optimizes priority inversion problem, and achieves better scheduling effect.

Key words: CAN FD, internet of vehicles, the early deadline first algorithm, schedulability, bus load, power function partitioning, exponential-power function partitioning, priority reversal