Re: Dropping marker signals?

[Joyce Poon <poonj@ecf.utoronto.ca>]

Hm... I think there is a clock oscillator chip thing available (I'm not
looking at the catalog right now).  On the other hand, it would seem to be
a little silly to have the circuit run on a clock or frequency diff from
the computer.

More on Hall Sensors & Speed Feedback:
I think we can use Hall sensors to measure speed. We just have to mount a
magnetic switch near the wheel and a companion magnet on the wheel.  So
every time the magent comes close to the switch, the signal will become
high/low (ie it'll change).  We keep track of the # of times the signal
changes within a certain period of time.  This is something that the Rice
U website talked about (though rather briefly). This is slightly different
from the interrupter blade method I wrote about before which is used in
cars (of GM make?).  

Joyce :)