The Arduino Uno-compatible board has an MCS-51 (often called 8051 instead) instead of the usual ATmega328P/ATmega168. Specifically, [ElectroBoy] uses the AT89S52 .

Both the Arduino Nano and Uno can be powered via their integrated USB connectors. This automatically supplies regulated 5V power to the board, allowing you to use any USB-supported power source ...

Arduino, the world's leading open-source hardware and software platform, today announced the launch of its next-generation UNO board, a significant re ...

Arduino has announced the new UNO R4 board family for prototyping and learning. The new models feature a faster microcontroller, a USB-C connector, improved power, Wi-Fi and Bluetooth LE, and more.