Modeling Synchronous Action Systems

The action systems framework has recently been applied to the area of asynchronous VLSI design. In this paper, we present a set of concepts necessary in the formal modeling of synchronous hardware, the synchronous action systems. These explicitly model synchronous two-phase behavior and are developed using the refinement calculus in the usual manner. The fundamental idea of synchronous action systems is to make a formal description transparent in the sense that its hardware implementation can be obtained by direct mapping. Such an implementation is composed of synchronous primitives called basic cells.