Abstract
Graphical communicating shared resources, GCSR, is a formal language for the specification and analysis of real-time systems including their functional and resource requirements. GCSR allows a modular and hierarchical, and thus, scalable specification of a real-time system. GCSR supports notions of communication through events, interrupt, concurrency, and time to describe a real-time system. In addition, GCSR allows the explicit representation of resources and priorities to arbitrate resource contention in a natural way that produces easy to understand and modify specifications. The semantics of GCSR is the algebra of communicating shared resources, a timed process algebra with operational semantics. The process algebra provides behavioral equivalence relations which can be used to verify the correctness of one GCSR specification with respect to the other.