Testing out Pixhawk outside the copter

Hey, my setup is the following:

Pixhawk with an RC reciever connected to it. Pixhawk is getting its power from the USB port connected to the PC


Do I need anything additional connected to the Pixhawk, for example the arming switch, in order to use the AUX pins?

What I want to achieve:

“Passing trough PWN values with Pixhawk” (Click the link)