On Tue, 21 Aug 2012 12:20:51 +1000 "David Meiklejohn" wrote: > The reason I (mistakenly) pointed to comparators is that I've been caught= by > what looks like a similar issue - where the PIC's outputs are demonstrabl= y > changing on actual hardware (e.g. LEDs are blinking), but the simulator > shows the same pins stuck on '0'. But when I've scratched my head over > that, I've found that actually the simulator was correct - the pin was > reading 0, despite working correctly as a digital output and the output > being high. Not due to RWM, nor external pin loading, but because when > configured as a comparator input it will read as '0', as per the data she= et. David, There is actually a very complete document on possible pin issues in the Microchip library (TB3009). It describes the comparator, AD and several others. I wish I had know about that info about a year ago when I bashed my head with the A/D being default on part A issue. John --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .