#21 read channel and value

[Johnny Osborne]

I am a newbie to the Arduino world; so i am hoping someone is willing to help. I am looking at the code and unable to figure out how to get the correct routine to read the incoming channel and the value being passed in.
My goal is to evaluate the incoming channel and value and then perform a function to perform another task based on the channel and value(1-255) being passing in.

currently using UNO R3, DMX RDM Shield, cheap 512 board, but open to other equipment if needed