On Fri, Apr 11, 2008 at 2:34 AM, Dave Roseman wrote: > > I'm just starting PIC programming, so please forgive me if this is too > simple or obvious a question. No such thing! We all have to start somewhere. Do you have any programming / electronics experience? To start, I would read up on how interrupts work in microcontrollers, and I would look into section 4.2.3 and 14.3.3 of the datasheet, 'Interrupt On Change'. Alex -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist