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Show CHAPTER 3 simulation. Specification of a speed-independent control-unit SPECIFICATION AND FUNCTIONAL SIMULATION The design of speed-independent control-units using the One-Hot state assignment technique requires both specification and functional consists of describing the functions of states (outputs), movement between states (transitions), and actions to be taken during movement from state to state. Such a specification consists of both syntax and semantics. .Syntax is the format portion of a specification which can be formally specified by something like a BNF description of a language or a. graph. Semantics is the low-level behavior underlying the syntactic definition. Functional simulation 1s essentially a test the designer runs on the syntactic definition he has just created to see if he properly understood the specification of the problem and the semantics of the implementation or solution to the problem. Functional simulation maps sets of current states and sets of input changes to sets of state transitions to next states and sets of output changes. Using this tool, the designer is able to partially verify that the design will perform the intended function. In the case of speed-independent .., control-\.l!1i ts, functional simulation is nearly equivalent to logic simulation because, while delay may have semantic meaning L the |
