A Flexible Time-Triggered Communication System Based on the Controller Area Network: Experimental Results
Controller Area Networks are normally used in event-triggered communication systems. These are known for not supporting composability in respect with the system temporal behavior. When using a time-triggered communication paradigm, such composability is achieved. However, common time-triggered systems rely on static message scheduling which compromises system flexibility. This paper proposes the use of centralized scheduling together with a planning scheduler to achieve flexible time-triggered communication on a CAN system. A model is deduced to allow the prediction of message production delays for a particular implementation using low processing power microcontrollers (Philips 80C592). Experimental results shown confirm the validity of the model. These results are also in agreement with a model for the scheduler execution time presented by the authors in previous works concerning the use of the planning scheduler in FIP-like networks.
KeywordsCommunication Overhead Controller Area Network Data Message Producer Node Scanning Window
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