Pin 4 (purple wire) on EMS22A (Digital Output) connects to pin 28 on Arduino Mega 2560. Pin 5 (red wire) on EMS22A (VCC) connects to VCC. Pin 6 (yellow wire) on EMS22A (Chip Select) connects to pin 24 ...

[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… ...