The NuMicro MG51 series is an embedded Flash type 1T 8051-based microcontroller. The instruction set is fully compatible with the standard 80C51 and performance enhanced. It supports 16/24 MHz core speed and features up to 32 Kbytes Flash memory, 256 Bytes of RAM and 1 Kbyte of auxiliary RAM (XRAM), 4 Kbytes of Flash loader memory (LDROM), 2.4V to 5.5V operating voltage, and -40°C to105°C operating temperature. https://www.campuscomponent.com/products/nuvoton-mg51fb9ae-de-3467-d/2208614000049530031