Application:
automatic selector of wine bottle from wine cellar: I would have a 132 bottle wine rack (1.2x1.8 m) to which I want to add LEDs (was thinking 5mm, red) below each bottle for rapid selection. I am currently considering a maximum distance of about 3 meters from my arduino mega 2560 R3 to the furthest LED. At most 1 LED would be ON at any given time.
I am reasonably new to all this so I am having a bit of a hard time choosing between charlieplexing my solution or multiplexing the LEDs.
With my understanding of chalieplexing, I would just need 12 digital IO pins and 12 220 Ohm resistors. Only 2 LEDs would be connected to each pair of IO pins, so the driving current would not be a problem. The downside is that I would have a lot of cables (264) to connect to the breadboard. I am also a bit unsure on the diameter sizing of the cable to employ.
Using a multiplexing approach instead, I would require 11+12 = 23 digital IO pins: 12 pins and 12 220 Ohm resistances for the anode lines, and 11 pins for the cathode lines. The idea was to use a single wire (AWG22) for each pin, to which the LEDs are attached by using a T-connector. I am not sure if I would need any more components for this solution (transistors?).
Could you suggest which solution would be best? (Also taking into account the coding difficulty in either case)
