I think I may not have been clear on my intent... I am using DCCppESP32 as my base station, so the signal is already being sent out TO the rails. What I am trying to do is now read that signal back FROM the rails at another spot on the track. That's why I was wondering why two arduinos were needed, I just want a simple accessory decoder that will pick up turnout commands and apply them to the appropriate servos on the PCA9685. Hope that makes more sense?