This format can...
Read-only support for the csv file format used by Visiontac VGPS-900™ and Columbus V-900™ GPS data loggers. These seem to be two brand names for the exact same product.
The the V-900 stores logs on a microSD card in a custom csv format. This format contains NULL chracters and fixed length fields, and therefore can not be handled by the normal csv module in GPSBabel.
Example 3.2. Conversion of a v900 csv log file to a gpx format
gpsbabel -i v900 -f 09040400.csv -o gpx -F outfile.gpx
The device support logging of trackpoints, waypoints, and voice recordings (.wav files).
If you create voice recording waypoints, a link (url) to the corresponding wav file is added to the waypoint. If you happen to use this for OpenStreetMap.org project, you can easily click on a waypoint and open the wav file from within JOSM. For this you must use gpx version 1.1 as the output file. The next example shows exactly how to do that.
Example 3.3. Conversion of a v900 csv log file to a gpx 1.1 format
gpsbabel -i v900 -f 09040400.csv -o gpx,gpxver=1.1 -F outfile.gpx