Circuit Idea

I have this idea. I was using the Lift one day when I began wondering how the "floor display" was able to tell which floor the elevator was in.

I think a circuit using IR sensors, possibly encoders and decoders, a flip-flop (probably a bistable) and a seven segment.

When the Lift breaks the IR, a transistor connected to the circuit would be reverse biased and its collector voltage shoots up. this could be used to enable a decoder(?) and the floor number is displayed. Now how would it know which floor is which i.e how does it make each floor unique? That's where the MUX comes in. But where exactly does it come in :?

Ideas guys. I need contributions.

No they use a much simpler method than IR. Just a small microswitch which is fixed on every floor. The moving elevator presses the switch which increments or decrements the display.

ELEVATOR DISPLAY

Ha, ha ha! :lol: So I was complicating matters eh? But I think the ideal was a good one, and perfectly realizeable.