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Changing the COM port for a USB device

Some devices that connect to the USB port expose a serial port (also called a com port). This includes USB environment controllers, such as the Tira or the GEWA ProgressStar, Smartbox BackBox units and bluetooth mobile phones.

The Grid 2 only supports com port numbers up to 16, and in some cases Windows will allocate a higher numbered com port.


To change the com port (in Windows XP):

  • Click on the Start menu
  • Right click on My Computer
  • Select Manage
  • Select Device Manager from the list on the left


You will now have Device Manager showing in the right hand pane.

  • Expand the group Ports (COM & LPT)
  • Double click on your device from the list (it will probably say USB Serial Port (COM20) or similar)
  • Select the Port Settings tab
  • Click on Advanced


You now have the Advanced Settings window showing. Here you can change the port number – for best results, select a number between 5 and 16.

If all these port numbers appear to be taken, you can select one anyway (often they are marked as still being in use when they are no longer used).

Click Ok on the windows to close them.

Note that device manager will still list the device with the original port number, e.g. COM20. This doesn’t matter, but if you unplug the USB device and then reconnect it, this should report correctly.

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