Handling event driven messaging in distributed flight critical systems

Using events rather than time to schedule messaging between nodes in a distributed avionics architecture can lessen data communication/processing requirements and reduce the cost of system expansion. Regulating bus access via the Flexible Time Division Multiple Access (FTDMA) method promises to enable event driven messaging without affecting the predictability of message response times. This paper investigates the FTDMA method in a distributed system handling both closed-loop control and discrete event detection/response tasks. Calculations are derived for placing an upper limit on message response times. The formula is then evaluated using empirical data from an experimental setup employing the Byteflight communications protocol.