XYXDI Arduino compatible Nano V3.0 ATmega328 Mini USB Microcontroller Board Cable OT8G Support for external 5V ~ 12V DC power supply 14 Digital input / output ports:TX,RX,D2 ~ D13 1 pairs of TTL level serial transceiver ports RX / TX Using Atmel Atmega328P-AU MCU Support power supply by 9V battery