The Arduino Leonardo is a microcontroller board based on the ATmega32u4. It has 20 digital input/output pins (7 of which can be used as PWM outputs and 12 as analogueue inputs), a 16 MHz crystal oscillator, a micro USB port, a power supply jack, an ICSP header and a reset button. It contains everything was needed to support the microcontroller; simply connect it to a computer with a USB cable or supply it with an AC/DC adapter or a battery to get started. The Leonardo differs from all previous boards in that the ATmega32u4 has a built-in USB communication, which makes a second processor unnecessary. This allows the Leonardo to appear as a mouse and keyboard to a connected computer, in addition to a virtual (CDC) serial/COM port. It also has other effects on the behavior of the board; these are described on the Getting Started page.This text is machine translated.