I wrote a little utility for my Mac, to connect the X-Plane flight simulator to other software which accepts GPS data in NMEA or Garmin Aviation format. This can be used to practice using GPS devices while on the ground.
I successfully tested the program with PocketFMS running on a PDA, transferring data via a Bluetooth Serial connection from the Mac to the PDA, and with a Garmin GPSMAP 495 unit.
The program is available for X-Plane version 8 and X-Plane version 9.
This application runs on Mac OS X. It is not a classical "X-Plane Plugin" but an external program which receives data from X-Plane (position, speed etc.), converts it to NMEA or Garmin format, and sends it to the serial device which you selected.
If you run X-Plane on Windows, you do not need this program, because X-Plane can send NMEA by itself on this platform.
If you want to be notified about changes or new versions, please send me a mail!
NMEA-Converter for X-Plane version 8
NMEA-Converter for X-Plane version 9
If you need the version which talks to Garmin GPSMAP units in Garmin Aviation format, please download this file - it is not yet very stable but it seems to work: X-Plane-to-Garmin-Converter for X-Plane version 9 (file updated on Feb 7th 2010 - the old one was corrupt).
Setting the Baud rate of your serial connection
Currently my program does not allow you to directly change the Baud rate (speed) of the serial connection. The main reason is that I did not need this feature myself, since my PDA does auto-detect the Baud rate.
If you want to connect a Garmin GPS unit, you can not use the USB cable which comes with the device, but you have to use the Serial cable which is sold separately by Garmin, and - if on a Mac - a USB-to-Serial converter.