A Multimodel and Computer Oriented Methodology for Synthesis of Sequential Discrete Systems

The synthesis of sequential discrete systems involves two major steps: 1) the abstract synthesis that yields a state-transition diagram, and 2) the structure synthesis that yields a realization. The structure synthesis, where the minimum state-transition diagram is assumed to be given, is discussed. Classically, two different models are in use to perform the structure synthesis: the finite-state model with memory span k=1, and the finitememory model. These classical models (the finite-state model extended for k¿1), are considered and other models are introduced that may be used for the structure synthesis. The latter, combined models with memory span k (k¿1), sometimes yield a better realization (according to specific engineering requirements) than the classical models. Structure synthesis based on the combined models and a rough evaluation of all the considered models from the standpoint of their realization is included in this paper together with an outline of a FORTRAN IV program being developed to automate the complete structure synthesis.