Analysis of Combinational Cycles in Sequential Circuits
نویسندگان
چکیده
This paper addresses the analysis of combinational cycles in synchronous, sequential circuits. A circuit that has a com-binational cycle does not necessarily have unstable output behavior: the cycle may be \false" for all reachable states and possible input sequences, or the unstable behavior on the cycle may not aaect the outputs. We provide a procedure to determine whether a circuit produces a unique, stable output sequence for every input sequence provided by the environment, under all possible circuit delays; such a circuit is called \output-stable". In addition, if a circuit is determined to be output-stable, then we provide a means of producing an equivalent sequential circuit, without com-binational cycles.
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