The processor core of Keyestudio NANO PLUS is ATMEGA328P-AU. It is as same as the official Arduino Nano in addition to driver file and USB to serial chip (CH340G).
It also has 14 digital input / output interfaces (6 of which can be used as PWM output), 8 analog input interfaces, 1 16MHz crystal oscillator, 1 mini USB port, 1 ICSP interface, and a reset button.
The ICSP interface is used to program the Atmega328P-Au. We can supply power with a type-CUS cable, the port VIN GND (DC 7-12V) and GND