TLC5940 libary http://playground.arduino.cc/learning/TLC5940 DMXSerial libary http://playground.arduino.cc/Learning/DMXSerial
TLC5940 pinout is the same as given in the library
PD5 is the DMX indicator led. (pin 5 on atmega168 and atmega328 based ardunio boards)
portC [0-3] are address pins to select DMX location in 16 channel steps. with the atmega168 and atmega328 based arduino boards these are A[0-3].