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

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

To accommodate more complex projects, the UNO R4 is fitted with 32 kB of SRAM and 256 kB of flash memory. The Arm Cortex-M4 core also features a floating point unit (FPU), bringing a performance boost ...