When programming a PIC, you're supplying a clock signal externally, so that the configured clock doesn't really apply. ______________________________ Reply Separator _________________________________ Subject: PIC programming Author: COROURKE@CCVAX.UCD.IE at internet Date: 11/5/96 2:55 PM Hi!, This may sound like a silly question but.... I've been reading the PIC data sheets and I understand the PIC pretty well and how it's programmed but I'm puzzled by one thing - the clock source.