Using a multiplexer, it is possible to make the Arduino read over a hundred buttons easily. A multiplexer/demultiplexer is an integrated circuit that selects one of several inputs and forwards them to the output. It requires a few control pins to determine which input to forward to the output.
Following are the ingredients required for this recipe:
- An Arduino board connected to a computer via USB
- A breadboard and jumper wires
- Four buttons
- A 4051 multiplexer or similar, which we can find at any electronics store and online at Digikey, Sparkfun, Adafruit, and so on
How to do it…
We implement a simple configuration using only four buttons. Here are the steps:
- Connect the Arduino GND to a long strip on the breadboard. Also ...