I want to make 2x arduino talk to each other via rf and using sensors. If 1x arduino detects an obstacle it sends a signal to another arduino to lyt a red lyt, if the first arduino area is clear it sends a signal to the 2x arduino to switch the red lyt to green.
This is to be used in a railway station, were arduino 1 is in the station arduino 2 is on the approach to the station, if 1 has a train then 2 is red, if no train in 1 area then 2 can proceed to station.
I hope that is understandable to you.
Plz try to help.