[jtdowney]

The format for the microcontroller I was speaking of is the .hex. IIRC the C18 compiler takes the code and compiles it to a COF (common object format) file which is then linked into a .hex file. Since that is what you send to the RC you should be able to dump it from the RC using the tool Alan provided. That will allow you to get the current .hex file which you can save in case you ever need it again. The executable format the microcontroller uses probably has a disassembler somewhere if not the format is generally not to bad from my experience working with Linux ELF files. Once disassembled you will have the original code in assembly language which will show you the logic you used assuming you have someone who knows PIC18 assembly.