From STG to extended-burst-mode machines

A method is presented for deriving a system of parallel extended-burst-mode (XBM) machines from a signal transition graph (STG) specifying required input-output behaviour. First, a primitive finite-state machine is derived as the most general, sequential solution, from which allowable concurrency can still be recognized. Output concurrency is dealt with by decomposition (output partitioning, omission of irrelevant inputs). The component FSMs, with input concurrency only, are tested for XBM feasibility and-if positive-their XBM specifications are constructed. The entire procedure is systematic and is illustrated by deriving two XBM machines from an STG with input and output concurrency. We propose to view the STG as the most general and most precise causal specification of any asynchronous design problem, above and beyond considerations of circuit models and delay assumptions