A region-based theory for state assignment in asynchronous circuits.
Jordi Cortadella, Michael Kishinevsky, Alex Kondratyev, Luciano Lavagno, Alex Yakovlev · 1997
State assignment problems still need satisfactory solutions to make asynchronous circuit synthesis more practical. A well-known example of such a problem is that of Complete State Coding (CSC), which happens when a pair of dierent states in a specication has the same binary encoding. A standard way to approach state coding conicts is to insert new state signals into the original specication in such a way that the original behavior remains intact. This paper proposes a method which improves over existing approaches by coupling generality, optimality and eciency. The method is based on the use of a class of \\ground objects", called regions, that play the role of a bridge between state-based specications (Transition Systems, TSs) and event-based specications (Signal Transition Graphs, STGs). We need to deal with both types of specication, because designers usually prefer a timing diagram-like notation, such as STG, while optimization and cost analysis work better at the state lev...