Button multiplexing

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.

Getting ready

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:

  1. Connect the Arduino GND to a long strip on the breadboard. Also ...

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