An Event Algebra Extension of the Triggering Mechanism in a Component Model for Embedded Systems

In this article we present how the component triggering in SaveCCM, a component model intended for embedded vehicular systems, can be extended by means of an event algebra. The extension allows components to be triggered by complex event patterns, and not only by clock signals or single external events. Separating the detection of triggering conditions from the definition of the triggered services permits more general components and thus increases component reusability. Providing event detection mechanisms within the component model means that triggering conditions are explicitly available for system analysis at design time. An event algebra is used to define the complex triggering conditions. This algebra has a relatively simple declarative semantics and well documented algebraic properties which facilitates formal and informal reasoning about the system. The algebra also ensures that detection of triggering conditions can be efficiently implemented with limited resources, which is critical in embedded applications.