I am going to use arduino interfacing with processng. Processing will be used for developing the interface which is going to be triggered when somebody walks by in. I have kind of rough idea right now using ping method to trigger interface on the screen. My question is
Lets say if I have two ultrasonic rangers, how can I trigger two different events on the same screen?i.e. how can I make two different arduino sketch talk to the same processing sketch? and I have this doubt because I am going to use two arduinos instead of one,because 1st event should be triggered when a person is 15meters away from the screen and another event when he gets closer like 6 meters away from the screen.
One more question, can I setup this physical environment using single arduino?
Thanks a lot,