Monday, August 27, 2012

NMEA O183 CRAZY MOUSE (not just a roller coaster in Greece)

Miller and Miller Boatyard recently had a customer looking to trouble shoot “crazy mouse” issue with his new laptop.  If you have dealt with the issue of a “crazy mouse” when interfacing NMEA 0183 devices you know how frustrating it is.  The mouse jumps all over the page pressing buttons at random, opening windows, closing windows and reeking havoc on any programs you might have running.  Using serial to USB converters make it all that much more difficult to remedy.  The issue arises from Windows registering a NMEA device as a mouse and misinterpreting the signals.  Our customer had just upgraded to Nobeltec Timezero Odyssey as well as upgrading his computer to one running Windows7.  He had done some research into t-shooting the NMEA “crazy mouse” issue and came to the conclusion that there was no solution for a system running Windows7.  I have seen some solution The key is in the timing…  Here is the trick.

1)      Unplug the offending NMEA device. If you are using a serial to USB converter leave the NMEA device connected to the converter but unplug the USB plug from you computer.
2)      Click the “Start” menu
3)      Click “Control Panel”
4)      Double click “System” icon
5)      Click “Hardware” tab
6)      Click “Device Manager”
7)      Click on the “+” next to the “Mouse and other pointing devices” icon

You should see only one (or maybe two) sub-icons here.  If you RIGHT click on any of these pointer devices you will get a drop down menu with “Update driver, Disable, Uninstall…” and so forth.  Here is where the timing comes in.  What you want to do is plug in your device and QUICKLY right click on the NEW icon that pops up under “Mouse and other pointing devices”  As soon as the new icon pops up UNPLUG THE DEVICE AGAIN, FAST.  The right click menu will remain open and with the NMEA device unplugged the “crazy mouse” will stop.  Click “Disable” and that’s it.  Next time you plug in the device it will register in the device manager but will come up as disabled.  Don’t worry if it takes you a few times to get the timing down.  I have done this a hundred times and it still can be tough some times.  If you have any questions leave a response or visit us at  Here is a great little discription of NMEA format in a text document,  It is handy when troubleshooting NMEA 0183 issue which I will address in future posts.