Mouse Interference with Serial Port

From the Time Nuts Mailing List:

I am running XP Pro with a USB laser mouse and a USB to serial adapter
to the T'Bolt.
The USB to serial adapter drivers are on hand and they loaded nicely,
with the computer setting the USB port to COM10.
To date I still have a conflict with the mouse.
The symptoms include: erratic mouse cursor that stabilizes (corrects)
after I disconnect the USB port to the T'Bolt.

The OS thinks the serial data coming from the TBolt is actually coming from a serial mouse. Therefore, the messages from the TBolt are interpreted as mouse movements. Typically, if you wait until the OS has completed booting before plugging the GPS receiver in the serial port, you will not have this problem.

It is not a driver problem or an interrupt conflict, it is just Microsoft trying to be helpful. Like many “helpful” features in Microsoft operating systems, this one is extremely frustrating and hard to eliminate.

Didier

If your adapter uses one of the popular FT232 chips from FTDI, then your “mouse” will be rediscovered from time to time, thanks for the “Serial Enumerator” feature present in the driver (see http://www.ftdichip.com/Documents/AppNotes/AN_107_AdvancedDriverOptions_AN_000073.pdf).

To disable this incredibly frustrating function, open the windows device manager and remove the serial mouse. Then open the properties of the serial COM port.

On the tab “Port Settings” click “Advanced” and in that window uncheck the box next to “Serial Enumerator”.

http://lh5.ggpht.com/_zKkNaqX3vkM/S-mRNIaXuoI/AAAAAAAAAw8/W6mWXYShUC8/s1600-h/serial-properties%5B2%5D.png

You'll have to repeat this whenever your USB-to-serial adapter is re-discovered, for example when you've moved it to a different USB port on your machine.

Greetings,

Chris