Jinx wrote:
> I'm sure someone somewhere has tried this for an older PIC
> 
> Any help greatly appreciated

Sometime back, an idea was floated on the piclist but I don't know how 
it worked out.

The plan was this.  Feed a microphone input through a  pre-amp and then 
to two separate op-amps setup as lowpass and highpass circuits.  Then 
each of these to comparators and into the pic of your choice.  Some form 
of agc or perhaps manual control with vu meters may be required for 
obtaining usable dynamic range.

The idea being to separate the users voice into low and high bands and 
produce waveforms that the pic could sort out for simple phrases such as 
  on, off, up, down, 1, 2, 3,... and so on.  The user must undergo some 
training.

I suppose if this idea is viable, at least for a small number of simple 
phrases enunciated well, that the pic could also modify the  front end 
analog characteristics perhaps (ie tune it) to help out a bit.  Plus, 
one could have more than 2 channels.

That's all I remember about the idea but it looked possibly feasible to 
me.  Whether it's feasible for you in the short time you have is 
something that could entertain us all!
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