Hierarchical State Machines: a Fundamentally Important Way of Software Design


Date Thursday May 6th 2004
Time 4:00-5:00pm
Venue George E. Pake Auditorium

PARC Forum

State Machines provide perhaps the best way of specifying and implementing the omnipresent event-driven (reactive) systems. Unlike the traditional finite state automata, however, the modern Hierarchical State Machines (HSMs) allow sharing of behavior among many states and therefore no longer “explode” with the increasing complexity of the systems they describe. This talk summarizes the key ideas behind HSMs, how they relate to other trends in programming and other disciplines (physics), and what impact HSMs might have in the future. The attendees will learn that HSMs are a powerful way of software design, no less fundamental than object oriented programming.


Miro Samek is the author of "Practical Statecharts in C/C++: Quantum Programming for Embedded Systems" (CMP Books, 2002), a contributing editor to C/C++ Users Journal, and an Embedded Systems Conference instructor. He is the Software Architect at Global Locate (San Jose, CA). He previously worked at IntegriNautics Corporation (Menlo Park, CA) and before that at GE Medical Systems. Miro earned his Ph.D. in nuclear physics at GSI (Darmstadt, Germany) where he conducted heavy-ion experiments. Miro welcomes contact at miro@quantum-leaps.com.

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