One more thing: gpsim DID catch the glitch but I did not look at the right place. Turn on the 'breadboard' and the IO pins on the pic turn red (high) = when input and RBPU on, and green when RBPU off (pins '0'). --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .