If you want to program in C (as opposed to Intellitek's graphical language, easyC) you will want to get the default code that Innovation First publishes. All the way at the bottom of
this page, there is a link for 2007 default code. The controller has not changed for a few years, so the 2007 code is the most up-to-date.
I've been looking for a good reference guide to this code, such as the one that IFI published in 2004, but I can find no such creature...it seems that basic documentation is missing...I just might have to write somthing up.
Let me know if you need more help than what I've given. I can write a "basic intro to the default code" manual if that's what you need.
JBot