Hi New to Arduino and have not found any explicit answer to this issue. The Uno can be powered from a computer via usb or via Wall-wart (~9v) according to the write up on the Uno Can I plug both sources into the Uno at the same time? What I want to do is use the wall wart for the normal power an…

power to UNO - both wall wart and usb

CrossRoads August 29, 2015, 11:31pm 2

Yes. If the barrel jack is >~7.3V, the barrel jack voltage will be selected for power instead of USB for power.

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