A question of protocol ...

affinite

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I have a Garmin 40 GPS giving location info to a laptop running Maptech Offshore Navigator. I also have a NASA GPS repeater "listening" and repeating position info. All three work together OK on simple NMEA protocol except that I cant upload/download waypoints from the software to GPS. The only way to exchange waypoint data is to change the protocol settings to Garmin. The problem is that the reapeater only seems to like vanilla NMEA and complains that is isnt getting GPS data.

At the moment I swap between GARMIN and NMEA for planing and on water but Id like a clean single protocol setup.

Any of the electronic wizards out there solved this one before ?
 
If memory serves me right there is no proper NMEA protocol to upload Waypoints to a GPS. Garmin has chosen to only use their own protocol to enable waypoint upload which is not so clever because when you change the settings it also change the output format of the GPS.
I had the same issue on a Garmin 126 GPS. These days I use a Furuno 32 GPS which is slightly better, but still requires manual intervention at the GPS to prepare the upload. To me it looks like none of these manufacturers actually use their own stuff because this functionality could have been set up in a much more clever way.

Arno
 
To upload, almost anything to a Garmin unit, you have to set it’s interface to ‘Garmin/Garmin mode’ it will then output positional data etc onto the NMEA interface in a mode that your NASA will not comprehend, hence the ‘no GPS data’ complaint.

Think of it as your daily exercise, walking to and fro all the data gear aboard, pressing buttons!
 
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