> I tried a resistor of 15K and a Cap of 0.1 mfd.
> But it does not work.
>
> Could someone advise me on how to get this working
> and how to calculate the frequency for a given value of
> R and C ?

I have 390k and 82pF on a PIC16F84A which runs nicely at 25kHz
with a 5V supply.

Usually for this kind of thing I use R x C to give a first
approximation to the period, then use the trial and error method
from here on. In my example above, 1/(RC) = 31.3kHz

Brent Brown
Electronic Design Solutions
16 English Street
Hamilton, New Zealand
Ph/fax: +64 7 849 0069
Mobile/text: 025 334 069
eMail:  brent.brown@clear.net.nz

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