820 ohm resistor goes between Arduino digital out pin and PS2 input pin. 1.2k resistor goes between PS2 input pin and ground. Or, you can use a logic level converter module. About. An Arduino library ...

PS2 Mouse Handler Library for Arduinos This library allows you to easily interface any PS2 compatible mouse to your Arduino using only 2 digital I/O pins. Most USB mice will allow you to connect them ...

[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… ...