Garmin GPSMAP 545 waypoint / route and the SD slot

[jarcher]

Is it possible to create waypoints and/or routes for a Garmin GPSMAP device using something like a text editor to create a file, then put that file on to an SD card and have a Garmin GPSMAP just read the routes off the SD card?

I have the lat/lon of a bunch of race course marks, and I want to put the routes for the various pre-defined courses into the GPS ahead of time. The only charting software I have is SeaClear II, which does not seem to export to Garmin, or even handle route creation properly.

Thanks...

[jarcher]

Hm, upon more research it seems that Garmin uses an undocumented binary format in a file called UserData.ADM. Very nice of them. There is a shareware utility called, generically enough, "GPS Utility" that allows you to enter waypoints and create routes and export them to the SD card.

GPS Utility - Home

I am still playing with it but it seems that it will do the job. Unfortunately for me, I need a SD card formatted by the Garmin unit to put the test data on, and my laptop can not write an SD card. So I either need to get a portable USB card reader or go to the boat, fetch the card, bring it home, write the date, then go try it out. I think I'll get a portable card writer.

[CapnRon47]

I purchased the Garmin 545s as my chart potter at the helm, it was small but large enough to read. But I was unable to download my tracks to the computer, because while it has an SD card it has no laptop connection. Fortunately I bought my daughter a Garmin 255W for her car and it takes the SD card and also has a computer connection. So I could load the SD card from the 545 and download it to Garmin Software on the laptop using the 255. I am thinking of getting the 255 as a backup for use on boat and car (it comes with street maps loaded) and then I can have a connection between the 545 and laptop as well.

cheers