>I never thought of it until just now, but I wonder how much resistance is >between the two grounds and two power supply pins. >Andy measured it's under 1 ohm (I do not trust the meter for readings lower thatn that) for C64 but I also saw troubles until I had both Vcc and Vdds tied together on the print/breadboard. Peter -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.