Your board needs two sorts of power to work : 12-24V power to turn motors, heat hotends, etc, and 5V ( or "logic" ) power to power the microcontroller ( the brain ).
There are three ways to provide 5V power to the board :
- By plugging a USB cable in, USB cables provide 5V
- By soldering a voltageregulator to the board ( and providing 12+24V, which the voltage regulator then turns into 5V )
- By providing 5V directly to the 5V power input ( next to the VBB power input )
If you want to keep it simple, the easiest solution is just to connect your Smoothieboard to your computer via USB.