Projectable Semantics for Statecharts

Statecharts is a language for the speciication of reactive systems. Semantics of Statecharts enforcing causality and synchronous hypothesis cannot be modular, and therefore do not allow general bottom-up construction of speciication and reuse of components. In this paper we propose both a global-consistent and a non global-consistent semantics which, in contrast to the known ones, are projectable, in the sense that the behaviour of a system projects into behaviours of subsystems as they result from considering each subsystem in isolation.