Hi Stephanos

I can't help with RC part, but I have recently
done PWM with a 16C84. I used four 8-bit
registers and just shifted them out an I/O pin.

For your application just one 8bit register will
be fine and if you set the TMR0 to generate an
interrupt every 41uS and then shift a bit out,
you'll have your 3KHz.

e.g.. 0000 0001 will be your slowest speed,
0000 1111 will be half speed and 0111 1111
will be the fastest although you may want
1111 1111 as the fastest.

Regards

Gavin
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vulcan@ihug.co.nz
http://www.geocities.com/TheTropics/Cabana/2625
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