We present a new semantics of Statecharts that excludes failures and a compositional formulation of this semantics based on Labelled Transition Systems (LTS). We consider a hierarchy of LTS equivalences and we study their congruence properties w.r. to statechart operators. 1 I n t r o d u c t i o n Statecharts are a specification language for reactive systems, introduced originally in [4]. The ...
