Abstract:
Currently, the controller area network (CAN) bus suffers from poor frame-identifier coding, a complex dynamic scheduling algorithm, and a large overhead of priority updating. To improve network utilization, ensure real-time data transmission, and improve the fairness of network use, we propose a dynamic scheduling algorithm in which the CAN message frame identifier domain is segmented, encoding the amplitude and variable frequency promotion (SSVP) according to the principle of priority dynamic promotion. First, we demonstrate the basic requirements for the dynamic scheduling algorithm, the promotion function, and its control elements (i.e., amplitude and frequency). We then define the segmented encoding for a frame identifier and promotion-function-based deadline; and discuss the initialization, updating amplitude, and the updating frequency of intra-class priority. We describe the SSVP dynamic scheduling algorithm and analyze its scheduling ability and communication time delay. The simulation results show that the SSVP dynamic scheduling algorithm is reliable for message communication and can improve network utilization.