Enabling/Disabling USB port?


I use a UD 3900 and I have a telephone recording device which saves its files to sd card. The device can be connected via usb to allow these files to be uploaded to a pc. I want the device to be permanently connected to the usb port and not to have to connect/disconnect cables however the device itself needs to be disconnected from the usb port in order to function. Is there a way to easily switch on and off a usb port on the UD3900? That is to easily enable a usb port to allow transfer or should I just get a usb switch and manually switch on the device when needed?


Hi Ed,

Thanks for posting. I’d be happy to answer your question.

The short answer is no, there is not an ‘easy’ way to switch off a USB port on the docking station. There are ways to disable USB devices within Windows (which I am assuming you are running) but I think trying to do so back and forth over time will be more hassle than it is worth.

The idea of using a USB switch is probably the best alternative, but depending on the type of device it may still not work as intended. You don’t mention which device you are using, but a quick Google shows me a large number of devices like you describe. In my experience with similar devices they function in one manner when not connected to a host and then transition to mass storage mode when connected to a PC to transfer data from internal memory. The question is will the device you are using correctly switch states when connected to a USB switch that is currently switched to the port that is not connected to the device in question.

I would presume the device you are using is a USB 2.0 device and as such our USB 2.0 switch (http://plugable.com/products/usb2-swi…) would be the most appropriate unit to try. We have a no hassle 30 day return policy so if it doesn’t work as expected you could return it for a full refund.

Let us know if you have any additional questions.

Thank you,

Plugable Technologies


Hi Bob.
Thank you for taking the time to answer my question. You correctly identified the function of the device. I will try the usb switch. Hopefully it will work. Its not expensive to try.
Thanks aagin


Hi Ed,

You are very welcome. If you have time please update this thread with your results (and the model of the phone recording device you are using if possible).