Save your project by multiplexing GPIO pins - The Byte Sized Engineer | DigiKey

[@colormaker5070]

Your method would result in a short if 2 buttons are pressed at the same time on 2 different rows. To fix this you would need to make the row pin as input (high impedance) after reading so there would not be a possible short for any row. In my opinion. Back in the days where 3 state outputs were not widely available we used row diodes to prevent shorting.

[@JonathanRansom]

This cleared up a few questions I had, thanks!

[@BeckyStern]

Great video, thanks Zach!

[@KaiseruSoze]

I like a 4-16 decoder with latchable outputs.

[@jtmcdole]

The Arduino page link is broken (page not found)

[@stivosaurus]

So, by multiplexing enough multiplexers, one could conceivably connect an infinite number of LEDs. Hypothetically speaking, of course.