Peter Cousens <peter@cousens.her.forthnet.gr> wrote:

> >     The trick is to wire an I/O pin to the TMR0 input, in parallel
> >     with the incoming signal... You make the I/O pin a hi-impedance
> >     input while TMR0 and its prescaler are counting incoming pulses,
> >     then you make it an output and use it to manually clock "extra"
> >     pulses into the TMR0 input until the TMR0 register increments.
> >
> >     At that point, you subtract the number of extra pulses that you
> >     generated from 256 (or whatever divide-by ratio your prescaler
> >     is set to)... The result is the value of the prescaler when you
> >     stopped counting incoming pulses.
>
> Yes I understand what your saying
> and thanks for the info
> But this will only give you 256
> resolution, to be of much use you realy need a few more bits

    No, Peter... It gives 16 bits of reolution.  Remember that the
    total pulse count is the 16-bit quantity represented by the TMR0
    register AND the prescaler, so the counter's range is [0-65535].

    -Andy

=== Andrew Warren - fastfwd@ix.netcom.com
=== Fast Forward Engineering - Vista, California
=== http://www.geocities.com/SiliconValley/2499