TMR1 on the PIC16C64 can be set up as an oscillator which can be used to cause an interrupt. The datasheet suggests that it is designed to be used with 32KHz crystals. Has anyone ever hooked this up as an R/C oscillator? I would like to use it with a pot to adjust the interrupt frequency from a few 10s of Hz to several hundred Hz. Actually the oscillator will probably be run much faster and the prescaler and/or TMR1 registers used to divide it down to the ~20Hz - ~500Hz interrupt frequency. Anyone try this before? Thanks! - Gary ------------------------------------------------------------------------ Gary Sutcliffe, W9XT Unified Microsystems ppvvpp@mixcom.com PO Box 133 Slinger, WI 53086 http://www.qth.com/w9xt 414-644-9036