I was surprised that this question had no answer on Stack Exchange and I can't find much about it elsewhere so, in the hopes that it will be useful to people other than myself, I'd like to ask:
How can one power two arduinos using the same power source? Such that the first is connected by barrel jack to a 12v transformer.
I saw this youtube video which very briefly mentions doing this by make the connections:
Ardu1 --> Ardu2
5V --> 5V
GND --> GND
This surprised me as I was not aware the 5V could operate as a power input. I was expecting the use of the VIN
pin somewhere along the line.
Am I correct in thinking that the second arduino would take power on it's VIN
pin from 5V
on arduino one?
If so, where should the second arduino ground to?