Recommended · for some experience
How to Control a Ton of Inputs using Shift Registers!
Why people recommend it
Explains how a shift register can scan many buttons or inputs from a handful of Arduino pins, sometimes linked alongside the same creator's output video.
Watch for: Uses the 74HC595 with diodes; there is a part two
In their words
Could you suggest a modification to your circuit to enable the use of a "shift register" technique to monitor the ACIN transitions (multiples detection circuits) (ref: [video] )
Daniel Auger on electronics.stackexchange.com, Feb 2017. CC BY-SA.
Also the tutorial I use ([video]) don't really agree with you.
Dan Chaltiel on arduino.stackexchange.com, Aug 2015. CC BY-SA.
