Garmin Data Card & SD Formats

Does anyone know where I can find info on the various Garmin card
formats and how to "change" them?

To be more specific, I have a couple friends that have GPS's that can
use G2 SD cards. One is a 420 and the other a 4212 (I think). I tried
a map (no unlock needed) from Mapsource and neither would read it.
Incorrect format error, as I recall.

I have a 178 and use Mapsource with no problem. But I also have an old
185 that uses the same Garmin Data Card, but get the same incorrect
format error.

Seems that there should be a way to use Mapsource maps????

TIA

Rick

        I don't have any of the GPSes you guys have to know much about your
problem. But in general, it doesn't matter what you guys have.

- The SD is SD, if some GPS can't read it then there may be something is
wrong with the GPS.

- If the GPS can't read some SD card then you may try different brand or a
newer firmware

- If the SD larger than 2GB then it's called SDHC which will require a
different hardware or firmware to be able to recognize the SDHC card.

- MapSource has nothing to do with the SD card. If the GPS can read the
card then it can read just about anything, and MapSource has almost nothing
to do with the GPS but a front-end to transfer data from computer to GPS or
memory card.

        I believe I may know what kind of problem you have at your end, but it
isn't part of the question so I don't know if I need to spell it out or not.

Actually, Joel, the above statement is incorrect. Or maybe it's more
incomplete.

For want of a better term, the "G2" GPS's will in fact read waypoints
and routes off the card, and write them, with no problem. The problem
is reading any maps. That's where the "incorrect format" error comes
in.

Mapsource writes a file, gmapsupp.img, in a "Garmin" directory on the
card. This file has all the selected maps in it.

I have a Street Pilot C530 that will read this map file and display it
with no problem. The two GPS's that take the G2 maps on SD give the
error.

There is a way to read a G2 card file, break it apart into individual
.IMG files and install into Mapsource. This would say the maps
themselves are the same. I'm assuming that gmapsupp.img file is put
together diffently or maybe there's another file in there that "tells"
the GPS it's G2? It seems that Garmin is using the same data, but
putting a gotcha' in there so you have to purchase new maps on the SD
card. Several people have complained about this, having to buy the
same thing twice - A G2 SD for their GPS _AND_ the same map on
Mapsource CD for planning.


As to the older unit. The Garmin Data Card is the same for both. I had
a pre-written card I had used in the older unit. Putting it into the
newer, it gave the format error. I erased the card using Mapsource and
put new maps on it. I could then use it fine in the newer unit, but
the older gave the format error. I would really like to be able to use
the older unit as a backup.

We live and cruise on a sailboat, so that old GPS could very well be a
lifesaver. Well, to be honest I have several laptops with other
software I could use, but it's still aggrevating to know I have a
perfectly good GPS that is all but useless.

One of our friends with the G2 unit bought the latest Bluechart
Americas. His GPS has US waters built in, but they're going to Canada.
Putting the Canadian charts on an SD doesn't work. So now he's got to
spend more money for a Canadian G2 SD for his GPS.



By all means, please do spell it out. I'm not really sure what you
mean. :-)

Rick

there are several different topics you are blending togther.... each to it's
own

#1 - a map is either download/DVD into Mapsource,
and then transferred to ANY GPS that will support that mapping firmware

#2 - a map purchased on SD Card is locked to that SD card (via card serial
number)
and can be swapped around physically into any GPS that supports that mapping
firmware.
However - the SD Card can't be copied to another card NOR can it be copied
to a PC
and therefore used with Mapsource.

#3 - old units vs new units vs SD card vs Mapsource -
well... the firmware has to be able to read the card,
along with the mapping data files on it..... and they have to be at the
appropriate level.

Sort of like trying to read a Word 2007 DOCX on any previous version of
Word.

just so others have a reference to the G2 maps -
here they are - (if this is what you are discussing)
https://buy.garmin.com/shop/shop.do?pID=6452
and - http://www8.garmin.com/bluechartrecall/
http://www8.garmin.com/cartography/g2vision/g2vision.jsp

and the GPS product list -
https://buy.garmin.com/shop/shop.do?pID=9618#productTab