This site uses cookies to offer you a better browsing experience. Find out more about how to manage cookies, or dismiss this message and continue to use cookies.

ETREX 30X - Can I move an installed Topo map to my SD card and still use it?

A new user to GPS but trying to learn. This is really a follow on to a recent question on the etrex 30x about freeing up the internal memory.

My etrex came with a free Topo map of Europe which has a file size of 3.62Gb, the total internal memory of the device (Etrex 30x) is 3.63Gb. This doesn't leave much space for tracks etc but to date it hasn't been a problem. However now that I have an update available for the device I can't down load it because as it reminds me I don't have enough internal memory space available.

The obvious solution would be to transfer the big gmapprom image file where the topo map lives to my SD card. I am told that yes I could do that but won't be able to use it, the image file is tied to the device to where it was originally downloaded and won't operate from the Sd card.

Is this correct?

If I move every file starting with gmapprom (GMA, SUM, UNL, image) to the garmin folder of the SD card would it work then?



  • Boyd 1955 Points
    edited October 2016
    I think it will work, however the only way to know for sure is to try, and I can't see any harm in doing so. The obvious first step is to fully backup internal memory to your computer and satisfy yourself as to the integrity of that backup. Then delete the files from internal memory, create a folder named Garmin at the root of a SD card and copy all three files to it. The only possible issue is that gmapprom is a file name normally reserved for a pre-installed map that originally ships with a device. Theoretically you can use any map filename if it has an .img extension, but that name might be treated differently.

    If it doesn't work, try naming all three files on the card to something else, like topo.img, topo.gma, etc.

    I think it's true that your map is tied to your device, but you will be using it on your device. Normally, maps with this form of copy protection can be placed on any media you like, but only usable in the original gps for which it was registered. This is different from the maps that Garmin sells on pre-loaded SD cards. They have a form of copy protection that only allows them to work on the original card, so you cannot copy them to internal memory for example.
  • sussamb 780 Points
    Boyd's correct. I've moved maps from my devices to the card, even those pre-installed.
  • claret 2 Points
    Thanks for the quick replies, I'll give it a go.
  • claret 2 Points
    Well I tried it and it works.
    For the benefit of others who must be in the same situation where the installed map fills the devices (Etrex 30X) internal memory and are new to all this as I am this is what I did.

    The disclaimer is to obviously make sure you are comfortable with and understand the following steps and most importantly can retrieve the situation if it goes wrong. I did quite a bit of searching through these forums to get an idea of the files I needed to move about.

    With the device connected to your PC use your PC's File explorer to see the internal files individually.
    Copy the following files - gmapprom img, gmapprom.gma and gmapprom.unl This is a very slow process, think it took nearly an hour.
    Paste them to a new folder on your PC. This is effectively a back up in case you lose the files some how. I also put a copy of the whole internal hard drive onto a separate hard drive as a diverse back up just in case.
    On the SD card fitted to the etrex I already had a folder named GARMIN with no files in it similar to gmapprom so I just pasted the gmapprom. img, gma and unl files straight into it.
    Then I deleted the gmapprom img, gma and unl files on the etrex internal drive.

    That's it , the etrex may be a little slower to boot up but it does and all my maps seem to work both on the device and on Basecamp.

    This forum is a tremendous resource thanks for the help.

  • Boyd 1955 Points
    Boyd said:

    satisfy yourself as to the integrity of that backup.

    Well you certainly took my advice to heart! :D Glad that it worked.
Sign In or Register to comment.
↑ Top