A tasking model for reactive systems

The problem of task specification and activation in a hard real-time software system is addressed. Discussed is the reactive systems model (RSM), which describes such a system as a finite set of reactions. Based on a rigorous analysis of the activation requirements, the model provides a classification scheme and specification patterns for describing reactions. The software architecture induced by the model and its special features concerning software engineering are presented and compared with those implied by the conventional tasking model. An executive named RSEX, which implements the model, is discussed