> if B <> SaveB then
>
>     if A is high then increment the controlled value
>     else decrement the controlled value
>
>     Set B to SaveB
>
> endif
>
> It is really that simple.

Not quite.  This doesn't take into account which B edge it was.  I you were
constantly going back and forth over a single B edge without any A edge
occurring, this algorithm would count in one direction instead of going back
and forth.


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Embed Inc, embedded system specialists in Littleton Massachusetts
(978) 742-9014, http://www.embedinc.com

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