Matt, Could you point me in the right direction for finding information on this "hidden" feature of the PIC firmware? I've never seen it mentioned in any other place. Thank you! Regards, Andres Tarzia Technology Consultant, SMART S.A. e-mail: atarzia@smart.com.ar -----Original Message----- From: Matt Burch [mailto:mburch@PINNACLET.COM] Sent: Sunday, September 12, 1999 21:15 To: PICLIST@MITVMA.MIT.EDU Subject: Re: multifunction ICSP programmer ... As for software on the PIC, there really is none required. The "debugging" feature I mentioned refers to the hidden ability to send serial data to and from the PIC firmware while it's being developed, so you can insert tx commands at strategic points to let you see what the thing is doing. I don't know how useful this will be to anyone else, but I personally use this trick a lot. ... mcb