Enter the ExtraCore library for Arduino, a software library that turns two or more Arduinos into a multi-core microcontroller with more pins than you’ll ever need.

[Trent M. Wyatt]’s CPUVolt library provides a fast way to measure voltage using no external components, and no I/O pin. It only applies to certain microcontrollers, but he provides example Ar… ...

Running out of GPIO pins? Learn how to connect multiple buttons to just one Arduino pin using clever wiring and resistor techniques. Perfect for compact projects, keyboards, or when using small boards ...