- Color: Blue - 14 Digital input / output RX, TX, D2~D13 - 8 analog inputs AO~A7, 2 x TTL level serial port RX/TX - 6 PWM ports: D3, D5, D6, D9, D10, D11; Adopt Atmel Atmega328P-AU singlechip - Supports serial download - Supports external 3.3V~12V DC