I now would like to use an external power source (battery).
Which pins should I use on the board to connect my battery (2 wires to connect : + & -).
Thanks for your help.
Erwan
The nano has a built in 5vdc voltage regulator so the most common method to power the board externally is wiring your voltage source (Input Voltage (recommended) 7-12 V ) to the Vin pin and ground pin.