Hello All: MPLAB allows programming an ID location--four Hex digits, or a non-protected checksum, which the programmer can read later. My question: has anyone found a way for the firmware to read this location so I can put the contents out a serial port or otherwise access them without pulling the chip and putting it back into the programmer? Most data books state rather clearly that "these locations are not accessible during normal execution." We need some simple way of maintaining and verifying version control during development and production. Our current plans are to store version information into the code, and have a command that will either send it out the serial port, or move it to an accessible memory location--sort of like DOS's "VER" command. Using the ID locations as a second storage location for validating the programming would be nice. I've got a couple of very expensive data loggers that have failed--with the most likely cause being an old version in one of the PIC's--but I've got no way to verify this since the whole thing is potted solid to survive 20,000 G impacts. Thanks **************************************************************************** ******** All legitimate attachments to this email will be clearly identified in the text. Please note our new address and phone numbers. William K. Borsum, P.E. DASCOR P.O.Box 462885 Escondido, CA 92046-2885 V&M&F) 760-796-7785 Direct) 760-796-7788