# 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.**

## Adafruit METRO 328

Arduino UNO-compatible development board built around the ATmega328P at 16 MHz with 32KB flash, micro USB, and Adafruit's signature black PCB with gold-plated pads.

[Details](https://openhardware.directory/devices/adafruit-metro-328) | [Markdown](https://openhardware.directory/devices/adafruit-metro-328/md)

## Arduino Mega 2560 R3

High-pin-count Arduino board based on the ATmega2560 at 16 MHz with 256KB flash, 54 digital I/O pins, 16 analog inputs, and 4 hardware UARTs for complex projects.

[Details](https://openhardware.directory/devices/arduino-mega-2560-r3) | [Markdown](https://openhardware.directory/devices/arduino-mega-2560-r3/md)

## Arduino Uno Ethernet

Arduino UNO with built-in Ethernet and microSD slot based on the ATmega328P at 16 MHz — a self-contained board for networked Arduino projects without needing a separate Ethernet shield.

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

## 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 Due

Arduino's first 32-bit ARM board based on the AT91SAM3X8E Cortex-M3 at 84 MHz with 512KB flash, 96KB SRAM, dual USB ports, 2 DACs, and 12 PWM channels in Mega form factor.

[Details](https://openhardware.directory/devices/arduino-due) | [Markdown](https://openhardware.directory/devices/arduino-due/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 Metro Mini 328 V2

Breadboard-friendly ATmega328P Arduino-compatible board at 16 MHz, 5V, with USB-C, STEMMA QT I2C port, 32KB flash, and CP2102N USB-serial chip — a compact modern drop-in for the Arduino UNO.

[Details](https://openhardware.directory/devices/adafruit-metro-mini-328) | [Markdown](https://openhardware.directory/devices/adafruit-metro-mini-328/md)