This paper studies the semantics of hierarchical finite state machines that are composed using various concurrency models, particularly dataflow, discrete-events, and synchronous/reactive modeling. It is argued that all three combinations are useful, and that therefore the concurrency model should be selected independently of the decision to use hierarchical FSMs. In contrast, most formalisms that combine FSMs with concurrency models, such as StateCharts (and its variants) and Hybrid Systems, tightly integrate the FSM semantics with the concurrency semantics. An implementation that supports the three combinations studied is described.
@Article{GLL99, author = {A. Girault and B. Lee and E.A. Lee}, title = {Hierarchical Finite State Machines with Multiple Concurrency Models}, journal = {IEEE Transactions on Computer-Aided Design}, year = {1999}, volume = {18}, number = {6}, month = {June}, pages = {742--760}, note = {Research report UCB/ERL M97/57} }