Toward a Basis for Protocol Specification and Process Decomposition

In a formalism of top-down design, we consider the decomposition of behavioral specications into interacting sequential components. The higher level of description speci es the operations to be performed in a major computation step. The goal is to incorporate a given interface speci cation in a lower-level speci cation that accounts for interactions with and among sequential components. This construction generalizes the earlier formalism of system factorization [14] to include interface protocols. It expands on the objectives of high-level synthesis by considering control-synchronization loops in scheduling. This paper presents a speci cation language for sequential process interaction and develops an interpretation based on nite-state-machines. Operations of minimization, composition and complementation are de ned; the last of these being the key to top-down decomposition. A small example is used to illustrate the ideas. Keyword Codes: B.4.3; B.4.4; F.3.1