Mini-statecharts: A compositional way to model parallel systems

Statecharts are well accepted in industrial applications for specifying parallel, reactive systems. Tools have been developed that supply the Statecharts specification method. Unfortunately a reference semantics has not been developed until now. Therefore, formal semantics and simulator-tool semantics often differ. This contribution outlines how to specify parallel systems with Mini-Statecharts, a special subclass of Statecharts. A compositional semantics of Mini-Statecharts is given in a fully functional way. It can be immediately executed by a suitable interpreter. Thus, we do not only define a theoretical semantics, but in addition provide the basis to write a simple program for simulating and prototyping Mini-Statecharts.