Newb Power Question

Using Arduino IDE 1.x
1

Just want to clarify If I can have the USB plugged in at the same time as the 9VDC wal-wart (board power jack).

thanks

2

GaseousAnomaly:
Just want to clarify If I can have the USB plugged in at the same time as the 9VDC wal-wart (board power jack).

thanks

Yes you can, and in the case where there is both USB and external power available the auto-voltage switch on the board will use the external power, cutting off the USB power.

Lefty

3

External voltage needs to be greater than 6.6V for the autovoltage switch to enable the external voltage vs the USB voltage.