I've written a timer tutorial (geared toward the 18F452, but generally applicable) which deals strictly with the math involved, since I could not find one that suited my purposes. It is pretty basic, but there are some timing tables included which might be valuable for someone. I'm not into including attachments when posting to a mailing list, but if anyone wants me to send them a copy just e-mail me and I will ship it to you. The only thing I ask is that you point out to me any errors you find. :-) Comments are welcome also, of course. Cheers, John -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads