Quote Originally Posted by astouffer View Post
... The power company makes small frequency adjustments over a 24 hour time so it always averages to 60Hz...
I didn't know they bothered.


If you're only interested in triggering an event every 60 Hz, have you looked at Darrel's interrupt I posted above? You can control the exact hertz you want a trigger without external parts. If you're not going faster than 16 MHz it's perfect for you.

Robert