Minimizing CAN Response-Time Jitter by Message Manipulation

Delay variations (jitter) in computations and communications cause degradation of performance in control applications. There are many sources of jitter, including variations in execution time and bus contention. This paper presents methods to reduce the jitter caused by the bit-stuffing mechanism in the Controller Area Network (CAN). By introducing some restrictions, such as a small reduction of available frame priorities, we are able to reduce the number of stuffed bits in the worst case. We also combine this with some of our previous work that reduces the number of stuffed bits in the data part of the frame. We show the actual penalty introduced by forbidding priorities, and we show the overall improvement by using these techniques together in a small case study.

• Type: Conference
• Year: 2002
• Where: RTAS
• Authors: Thomas Nolte, Hans Hansson, Christer Norström
• Keywords: Available Frame Priorities, Communications Cause Degradation, Delay Variations, Embedded Systems, RTAS 2002