I'm building a project using an Arduino Nano, and I can't quite work out how to power it (other than USB). Elsewhere in the project, I'm powering a pump using a 12V adapter, capable of 3amps. The pump pulls a maximum of about 1.2amps - so I'm wondering if I can also rig the nano up to this. Hunting around the interwebs, I find that ...
The Arduino Nano can be powered via the Mini-B USB connection, 6-20V unregulated external power supply (pin 30), or 5V regulated external power supply (pin 27). The power source is automatically selected to the highest voltage source.
... I'm reading that this means I can run power through pin 30. But, I'm left with two questions ...
Where the devil is Pin 30? It's not easily identifiable from the board.
Do I just connect ground on the board up to ground on the supply?
Thanks for any help.