Updating a 16-year-old GPS receiver
May. 21st, 2022 06:53 pmThere's a geocache I've got my eye on that has loads of stages to it, and as useful as the Geocaching Android app is it is very fiddly to work with child waypoints on it. So I thought I'd dig out a classic Garmin yellow eTrex I've got and give that a go. There's a snag though: it's so ancient (it's the same one we used when
talismancer first introduced me to geocaching in 2006!) that it had fallen foul of the GPS date rollover in 2019 and was convinced that the year was sometime in 2002!
I know that several GPS receivers have firmware updates to fix this (even very old models) so I thought it's worth a try, and if not I can always ignore the incorrect date (assuming that doesn't cause problems with getting a GPS fix). So, first up was the Garmin website and their WebUpdater which detected the GPS (handily my new PC has a real serial port, and the serial cable I made up years ago based on this somehow still works) and proclaimed that I was running the latest version! Some more searching threw up a changelog which had the latest version as 2.14... which was rather confusing, as the eTrex claimed it was actually on 3.10.
So I did more digging and found this archive which had some v3.x firmware installers and suggested (based on the folder naming) that they would work on a basic eTrex. Well, I don't have anything to lose, so I pulled down the v3.30 updater, ran it, and it merrily detected the eTrex. A couple of minutes later it'd loaded the new firmware on and everything seemed to be working.
The later versions hadn't been picked up by the wayback machine but they gave me a hint for what to search for and I tracked down the actual latest v3.70 firmware on the Garmin website. It appears that there's two hardware revisions of the basic yellow eTrex, and the newer revision uses v3 firmware. Anyway, after running the 3.70 firmware update I did a factory reset, left it outside for a while to get a fix, and one of those updates has fixed things as it's now showing the correct date!
I know that several GPS receivers have firmware updates to fix this (even very old models) so I thought it's worth a try, and if not I can always ignore the incorrect date (assuming that doesn't cause problems with getting a GPS fix). So, first up was the Garmin website and their WebUpdater which detected the GPS (handily my new PC has a real serial port, and the serial cable I made up years ago based on this somehow still works) and proclaimed that I was running the latest version! Some more searching threw up a changelog which had the latest version as 2.14... which was rather confusing, as the eTrex claimed it was actually on 3.10.
So I did more digging and found this archive which had some v3.x firmware installers and suggested (based on the folder naming) that they would work on a basic eTrex. Well, I don't have anything to lose, so I pulled down the v3.30 updater, ran it, and it merrily detected the eTrex. A couple of minutes later it'd loaded the new firmware on and everything seemed to be working.
The later versions hadn't been picked up by the wayback machine but they gave me a hint for what to search for and I tracked down the actual latest v3.70 firmware on the Garmin website. It appears that there's two hardware revisions of the basic yellow eTrex, and the newer revision uses v3 firmware. Anyway, after running the 3.70 firmware update I did a factory reset, left it outside for a while to get a fix, and one of those updates has fixed things as it's now showing the correct date!


