>...mileometer...

Odometer.

>Firstly I think it is essential to use TMR0 to count prop shaft revaloutions

This will give you the number of revolutions of the shaft, not the
distance.  If you want to know the distance, you have to have two sensors,
one of which "closes" before the other in forward, and after in reverse.
Otherwise, you can't drive backwards to get rid of excess miles. <G>  (My
brothers-in-law did this to their parents 1960's-era Plymouth).

You also need to know this information from a very slow movement as well -
Just think of the great Northeast part of the country and it's many miles
of parking lots at rush hour.

I have this problem with counting mileage.  What's really important is to
know how many times the crankshaft turned over, as is done in tractors and
aircraft (they are rated in so many "hours" at a particular RPM).    A
comparison of miles traveled to revolutions would tell a lot about
low-speed operation, which kills cars.  Another nice thing would be to know
actual hours of operation vs. hours at RPM to know how much the car sat on
a "parking lot."

>Oh by the way I can send Male again cause new modem fitted and it works

Sending Male, huh.  That's kinda pushing the envelope, isn't it?  Or are
you one of those smut peddlers <G>

Andy

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                     Andy Kunz - Montana Design
          Go fast, turn right, and keep the wet side down!
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