[tiny nit-pick] James Paul on 2001-06-13 08:44:56 AM claimed that > And as far as the PIC pin is concerned, it's general knowledge that > a TTL/CMOS output is better at sinking current than at sourcing it. Yes, everyone knows this. However, everyone is wrong :-/. All the CMOS devices I work with have exactly the same current sink as current source. For example, the PIC16F7X data sheet http://www.microchip.com/0/lit/pline/picmicro/families/16f7x/index.htm http://www.microchip.com/download/lit/pline/picmicro/families/16f7x/devices/16f77/30325a.pdf says, on the first page, High Sink/Source Current: 25 mA . I would be surprised to learn of any PIC output that had a significant difference in current sink vs. current source (except for ``open drain'' pins like RA4). -- David Cary electronics nit-picker -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body