This paper compares different scheduling policies applied todistributed systems intended for automotive real-time controlapplications. We describe the characteristics of systems using fixedpriority (FP) and static cyclic (SC) scheduling of processors and buscommunication, with combinations ranging from FP bus-FP processors to SCbus-SC processors. FP bus is represented by the Controller Area Networkprotocol (CAN) and SC bus by a Time Division Multiple Access (TDMA)protocol. We also study the effects of using a global time base. Ourmain concern is control performance, including input and output jitterand control delay and therefore the response time of a sequence ofcontrol tasks and the related communication. For each systemconfiguration we analyze the expected response times of a series ofcontrol related tasks (delay) and the temporal variation of the inputand output instants (jitter)
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