arduino uno smd rev3 [a000073] arduino <h1>arduino uno smd, rev3</h1> <br> <p>the arduino uno is a microcontroller board based on the atmega328 (datasheet). it has 14 digital input/output pins (of which 6 can be used as pwm outputs), 6 analog inputs, a 16 mhz crystal oscillator, a usb connecti