Power source is an important part because we’re going to have many boards/parts that need power and we no longer have the NXT Brick as a source..
To stay in the “Lego realm” a good solution is to use the Power Function battery boxes.
There are different battery boxes available in Power Function :
The basic one, using 6 AA batteries.
So we need to customize a cable like this one:
When plug in the battery box, here what voltage we have:
Switch is on Left
Switch is on Right
So we can see that the :
So, when you have one Power Function cable, you can make two power cables like this one:
The inner wires will be used to plug directly on a motor and the outer ones to plug on a board, like this: