A digital system modeling philosophy and design language

With the increasing complexity of digital systems, a new approach to system decomposition and modelling must be developed. Such an approach must not only permit a system to be described in a modular fashion, but the basic system modules must be able to be decomposed to allow a precise description of the module function. In this paper, a modelling philosophy and language are presented which permit the system designer to: (1) specify the system design in a hierarchical, modular fashion; (2) describe the function of each module by independently specifying the structure and the control function of the module; (3) build arbitrarily complex structures and control functions through the use of macro like definitions; and (4) handle the problem of specifying complex concurrent control functions in a straight forward and unambiguous manner. Examples are used throughout the paper to clarify the semantics of the language. A complete unit design and a Backus Normal Form (BNF) specification of the language syntax are presented.