One of the ports on the parlor board is designated as a USB On The Go (OTG) port. I ran into that same problem a while back.
See this link for more info:
You can connect a USB hub to the working port or I hear (but cannot confirm ) that you may be able to reconfigure the kernel to get both ports to work in normal USB mode.

-Alex Ray

On Apr 13, 2013 9:39 PM, "William Bryan" <> wrote:
One of the USB ports on our Parlor board is not functioning. Upon booting the kernel, it displays that it finds a USB 1.1 Hub (3 ports) and a USB 2.0 Hub (3 ports). When plugging a USB camera into the ports, one of them allows the OS to interface with the camera, while the other does not.

Using a multimeter, I found that the working port has +5 V at the + terminal in the USB port, while the + terminal in the other USB port appears to be floating, as it hovers around +5 mV.

What can be done to resolve this problem?


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