It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 8 analog inputs, a 16 MHz crystal oscillator, a mini USB port, an ICSP header and a reset button.
Note that ICSP (In-Circuit Serial Programming) header is used to program the firmware to ATMEGA328P-AU, but generally the chip has been preburned before leave the factory. So use it less.
The keyestudio Nano can be powered via the Mini-B USB connection, or female headers Vin/GND (DC 7-12V).
