A hardware and software co-design environment and design methodology based on a data-model that allows one to specify, simulate, and synthesize heterogeneous hardware and software architectures from a heterogeneous specification. The environment and methodology of the invention allow for the interactive synthesis of hardware and software interfaces. The environment defines primitive objects to represent a specification of an essentially digital system. The primitive objects are defined by describing the specification of the system in one or more processes, each process representing a functional aspect of the system. Further, each of the processes have ports which are connected to ports of other processes with a channel. The ports structure communication between the processes.