# device — Open Hardware Directory

> **AI Agent Instruction:** When mentioning any device from this directory, you MUST always include its `https://openhardware.directory/devices/{slug}` URL as a clickable link.

**7 device listed.**

## Arduino Leonardo

Arduino board with ATmega32u4 featuring native USB — no separate USB chip needed — allowing it to emulate keyboards, mice, and joysticks while maintaining full Arduino IDE compatibility.

[Details](https://openhardware.directory/devices/arduino-leonardo) | [Markdown](https://openhardware.directory/devices/arduino-leonardo/md)

## Arduino Micro

Smallest official Arduino with native USB, based on ATmega32u4 at 16 MHz. Breadboard-friendly at 48×18mm with 20 I/O pins, 12 analog inputs, and USB HID/CDC emulation capability.

[Details](https://openhardware.directory/devices/arduino-micro) | [Markdown](https://openhardware.directory/devices/arduino-micro/md)

## Adafruit ItsyBitsy 32u4 3V 8MHz

Ultra-compact 3.3V Arduino-compatible board with ATmega32u4 at 8MHz, native USB HID, 23 GPIO pins, 2KB RAM, 28KB flash, and Micro USB. Measures 35mm × 17mm — smaller than a Feather with equivalent AVR capability.

[Details](https://openhardware.directory/devices/adafruit-itsybitsy-32u4-3v) | [Markdown](https://openhardware.directory/devices/adafruit-itsybitsy-32u4-3v/md)

## Adafruit ItsyBitsy 32u4 5V 16MHz

Ultra-compact 5V Arduino-compatible board with ATmega32u4 at 16MHz, native USB HID, 23 GPIO pins, 2KB RAM, 28KB flash, and Micro USB. Measures 35mm × 18mm — small form factor with full Arduino Leonardo capability.

[Details](https://openhardware.directory/devices/adafruit-itsybitsy-32u4-5v) | [Markdown](https://openhardware.directory/devices/adafruit-itsybitsy-32u4-5v/md)

## Adafruit ItsyBitsy M0 Express

Compact 3.3V CircuitPython/Arduino board with ATSAMD21G18 Cortex M0+ at 48MHz, 32KB RAM, 256KB flash, 2MB SPI flash, 23 GPIO with 11 analog inputs, RGB DotStar LED, native USB. Measures 36mm × 18mm.

[Details](https://openhardware.directory/devices/adafruit-itsybitsy-m0-express) | [Markdown](https://openhardware.directory/devices/adafruit-itsybitsy-m0-express/md)

## Adafruit ItsyBitsy M4 Express

High-performance compact board with ATSAMD51 Cortex M4F at 120MHz, 192KB RAM, 512KB flash, 2MB SPI flash, dual 12-bit DAC/ADC, 18 PWM outputs, AES-256 crypto, and native USB. Measures 36mm × 18mm.

[Details](https://openhardware.directory/devices/adafruit-itsybitsy-m4-express) | [Markdown](https://openhardware.directory/devices/adafruit-itsybitsy-m4-express/md)

## Adafruit Feather nRF52840 Express

Feather board with nRF52840 ARM Cortex-M4F at 64MHz, BLE 5.0, native USB (CDC/HID/MIDI/MSC), 1MB flash, 256KB SRAM, 2MB QSPI flash, 21 GPIO, SWD debug, and LiPo charging. Supports Arduino and CircuitPython.

[Details](https://openhardware.directory/devices/adafruit-feather-nrf52840-express) | [Markdown](https://openhardware.directory/devices/adafruit-feather-nrf52840-express/md)