Thread: How to see a GPSmap 278 as a mass storage device?

SF, it's quite possible to load a detail map using command prompt or a text command in a .bat file and invoke WebUpdater to do the task. GPSMAP278 uses the same regions as StreetPilots 26x0 & 27x0 and that's region 3 for the basemap, 49 for the primary detail map and probably 50 for an oem map [that's reserved for a map with dealer PIO's for instance and they're usually quite small, won't work with all maps particularly bigger CNNT types] I'm not sure rgn 50 is available to all these older units so best not to write anything to it unless you're sure. Region 10 is the Garmin data card. They are usually supplied pre-loaded with mapping and can be reprogrammed as Giomen said, or you can write the new map with the card in the unit using similar commands as for the other 2 regions. That also works with SPc3x0 to write gmapsupp.img as an rgn to the SD card when inserting in the unit [tested] and i suppose would work to write to the inserted CF card of 26x0, but it's quite academic there as card reader/writers for those media are freely available unlike for Garmin data cards. Those region numbers are in Decimal by the way.

You can read about the commands for rgn49 [it's the same for 50] here: [Only registered and activated users can see links. ]. Garmin data card info here: [Only registered and activated users can see links. ].

Another supplementary map [gmapsupp.img] can be sent to the unit using Sendmap20, or from a PC installed version via MapInstall or MapSource. I don't know to what region that map is sent, if anyone knows please post it.

If you want to use the Updater.exe flash for maps, you need to change the map's .img extension to .bin, load it into RGN_Tool and save it as an .rgn file. Then open the file in a hex editor and search near the start of the file for 'R' in plain text [hex 52], you'll usually find it at offset 0x31 from memory. The next number after 52 will have been auto-saved as 33 by RGN_Tool, so you can also search in hex for '52 33'. Then change 33 to the region you require in hex [03 for rgn3, 0A for rgn10 (media card), 31 for rgn49 or 32 for rgn50 as applicable] and save the changes to the rgn file. The rgn file can then be flashed using Updater.exe. You don't need to find pre-boot with these units, they are constantly in a kind of pre-boot mode.

Whichever method you use, your currently loaded maps will be overwritten of course. If you want to just delete a supplementary map to gain more space for a primary map, you can do that using Sendmap20.

PS: These units cannot be updated by GE for either mapping or software. Use either MapUpdater for purchased maps or WebUpdater for software, audio packs etc.