Performance analysis of mixed asynchronous synchronous systems

Abstract

The paper is concerned with the timing analysis of a class of digital systems called mixed asynchronous-synchronous systems. In such a system, each computation module is either synchronous (i.e. clocked) or asynchronous (i.e. selftimed). The communication between modules is assumed to be selftimed for all modules. We introduce a graph model called MASS for describing the timing behaviour of such architectures. The graph contains two kinds of nodes, synchronous and asynchronous nodes. The operation model of a MASS is similar to that of a timed marked graph, however, additional schedule constraints are imposed on synchronous nodes: A synchronous node can only fire at ticks of its local module clock. We analyze the behaviour of MASS, in particular period, periodicity and maximal throughput rate.