Response-time analysis of a CAN network used for supervisory control and diagnostic systems

This paper refers to construction methods of Supervisory Control and Diagnostic Systems (SCDS) based on a CAN bus. Emphasis is put on the construction of such systems. Meeting real time constraints has become one of major aspects of this elaboration. The study enumerates possibilities of using various communication mechanisms of CAN, applicable for real-time systems. Proposed solutions are especially suitable for general-purpose SCDS. Principles of real-time analysis for CAN bus based systems are discussed as well. An example of SCDS implementation for a Swiss Light Source (SLS) large scale accelerator project is given. Time analysis is made for the constructed system with real-time conditions met. Experiments performed in the SLS confirm the results of the analysis.