How to store more than one map on an SD card

[BigJohnny59]

I am very new at this.  I installed one map on a micro SD card.  I decided to install a second map on that same micro SD card, and discovered it simply over-wrote the first map. 

There is a folder on the SD card named Garmin that holds the map files.  And apparently the new map simply over-wrote that Garmin folder with a new Garmin  folder on the SD card.

How can I install more than one map on the SD card?  Or will I have to have a separate SD card for each map?

Thanks

[Boyd]

What GPS do you have? it makes a big difference. Also, was the card inserted in the GPS when it was connected to your computer? Or was the card in a USB reader or internal computer slot? That also makes a difference.

[BigJohnny59]

It's an Oregon 550T.  I have an 8GB micro SD card. 

I installed the maps on the card using a card reader.   I installed one map, inserted it in the Oregon 550T, and it found it perfectly.  So I took the SD card out of the Oregon 550T, installed another map on the SD card (using the card reader again), and that is where I discovered it simply over-wrote the first map.

Thanks

[Boyd]

Your GPS will recognize any map file with an .img extension. This should also work with a map on a card. If you connect the GPS itself to your computer, then use Basecamp/MapInstall to send maps, the software should be able to figure this out all by itself and will assign unique names to each map.

However, if you have the card in a reader then the software won't know what kind of GPS you have. Older Garmin handhelds would only recognize a single file name - gmapsupp.img. So the software will fall back to the lowest common denominator and always name a map gmapsupp.img if the card is in a reader.

There should be several solutions. The easiest is probably just to put the card in the GPS and connect it to your computer, then let MapInstall figure out the rest.

Another possibility is to copy the file GarminDevice.xml from the GPS to the card. This file is used to describe the GPS capabilities to MapInstall. So if you copy it to a card, MapInstall will think the card actually *is* your GPS. It should then assign unique map names.

Then there's the brute force approach. After sending the first map, manually change the name form gmapsupp.img to WhatEverYouLike.img. Then send another map and repeat. This will also work with Mapsource.

Personally, I rarely use Garmin's new software like Basecamp and MapInstall. So I use the brute force approach with Mapsource most of the time. 

[BigJohnny59]

Thanks for the quick and very thorough responses.  It's starting to make sense.  I was able to get all the maps installed.  Appreciate all the patience for a "newbie" like me!