A compositional method for the top-down design of real-time systems

To specify and verify real-time systems, we consider a formalism based on Hoare triples (precondition, program, postcondition) which are extended with a third assertion, called commitment, to express the real-time communication interface of the program. In this paper we axiomatize concurrent programs that communicate by means of a common bus. To support top-down program Verification we formulate a compositional proof system for these extended Hoare triples. The method as illustrated by a distributed arbitration protocol.