Even if you sync both PICs in software (because of power up timers and other issues) you can't control the internal divide-by-four clock. Actually I suppose you can only get them completely syncronized one fourth of the power-ups. The ouputs will not switch at the same internal clock cycle causing spikes and maybe letting the smoke out the devices if you're unlucky.. -Henrik -- ( "If we aren't supposed to eat animals, why are they made of meat?" ) mailto:henrik@lewander.com c[] http://henrik.lewander.com