USB to Serial COM Port Assignment

We sell a number of USB to Serial adapters that will allow you to connect a serial device to a USB port on your computer. Installing the drivers will set up a COM port in the device manager, and from then on your computer will think that it is using a serial communication port.

Generally Windows will automatically assign the USB to Serial port as the first unused COM port… but Windows can see many things as using a port. Often if a device has polled a port, Windows will show it as In Use.

Sometimes as you disconnect and reconnect the USB to Serial, it will set up a new COM port each time you reconnect the adapter. (We had a test machine that got as high as COM14). If this is happening you can simply reassign the COM port and Windows should remember the new port and continue to use it in the future.

Changing the COM port is simple, we have detailed instructions on our USB to Serial Support page.