Hello. I'm working on the Iris+ drone of my University in order to add some new sensors (it's the purpose of my master thesis) but I don't have experience in programming. Right now, in order to make the first simple attemp, I would like to connect an external led to the pixhawk. The idea is to connect it to one of the I/O digital pins and then set the code to give voltage and make the led shine in some particular situations. Are you able to tell me wich file of the firmware should I modify andhow in order to change the on boot configuration of the pins?

Thanks.