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A comment on State Machines. Parent comment

Re:State Machines by nova on Tuesday May 15, 2012 @04:37AM (#3975597)
I like the approach of "Practical UML Statecharts in C/C++", at least the simple one. More or less, keep the state on a function pointer, each state is represented by a function which gets incoming messages or events and returns the next state. I used it for a RS485 protocol running on a microcontroller quite successfully.
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Re:State Machines by pierrebouchet on Tuesday May 15, 2012 @05:56AM (#3975768)
There is also the HSM (hierarchical state machine) extension of this concept (by the same author, not sure it's in the same book) where a given state either handles an event or returns a pointer to a "superstate" that handles it. This kind of "behavioral inheritance" allows for a much more compact code.

Compact and efficient state machines are immensely useful when working with small microcontrollers that don't even run an OS.

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Re:State Machines by nickmain on Tuesday May 15, 2012 @12:15PM (#3977246)
The other nice thing about HSMs are concurrent sub-states. They allow clean modeling of the orthogonal aspects of the state.
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