>Does anyone recall alternative methodologies?
>Has anyone got a set of semantic rules?

I do mine in a matrix.  Rows are states, columns are stimuli.

Each cell contains two lines:  New state, Action

An empty cell implies no change.

These are very to implement in this fashion in a PIC (done it several
times), even easier in a Z-80.

Sometimes it's handy to have both the old state and the new state available
to the Action function.

The other nice part about this technique is that it lends itself to easy
reading in the source code (as long as you use a fixed-pitch font), and to
compression (I have used offsets from the current state in the ROM table).

Attached is a state table I did for an IR-based alarm clock/cable TV
converter in a PIC'57.

Andy

Attachment converted: wonderland:STATETBL.SRC (TEXT/CSOm) (0000BAD6)
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Andy Kunz               Life is what we do to prepare for Eternity
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