Where is your Autonomous() function? It (or a prototype to it) should be before the routine that gets the error, Process_Data_From_Master_uP(). If the routine is in a separate file, then the prototype needs to go in a header. If Autonomous() is in the same file, then put it before Process_Data_From_Master_uP().
If you build the box, then you don't need the joystick trigger. One or the other. If you don't build the box, then it is easier to just use a joystick trigger.
p1_sw_trig should be valid..... it is.
http://ifirobotics.com/docs/legacy/2...2-apr-2004.pdf has a list of the IO definitions, you can find everything there. If you look at ifi_aliases.h it will tell you what the definition for everything is. If you created a C file for your code, you have to include ifi_aliases.h to use... anything (OI data, PWM outs, Analog, Digital inputs).