Thread: Basemap Replacement in Regional Devices without Mass Storage Mode Access.

Preamble:

Older automotive units such as StreetPilot c3x0/26x0/27x0 and early outdoor units such as GPSMAP 60/76C(S)x and other GPSMAP's use region 3 for basemap storage. As the space available on the unit for storeage is limited, most were supplied with a Regional basemap which included reasonable detail for the market area intended for the unit, and only some very basic roads for the rest of the World.

Typically Garmin will advise that these regional basemaps are fixed and cannot be replaced with another region however that's untrue. An Americas model can be flashed with an Atlantic or Pacific basemap and vice versa. In many cases there may be insufficient space available to flash a large World basemap, however it should be possible to at least flash the regional map suitable for the area in which the unit's being used.

Tutorials:

1. Attached below are several basemaps in rgn file format ready to be flashed via Updater.exe to region 3 of a compatible unit. Approximate extracted sizes are shown in brackets.

Spoiler: RAR files

Americas: 1. [Only registered and activated users can see links. ] 2. [Only registered and activated users can see links. ]
Atlantic: 1. [Only registered and activated users can see links. ] 2. [Only registered and activated users can see links. ]
Pacific: 1. [Only registered and activated users can see links. ] 2. [Only registered and activated users can see links. ]
World: 1. [Only registered and activated users can see links. ] 2. [Only registered and activated users can see links. ] 3. [Only registered and activated users can see links. ]

To flash one of the ready-made gmapbmap.rgn files:

• Confirm your unit is compatible BEFORE flashing
• Take note of the basemap presently loaded to your device and check what size it is, look for a similar sized basemap for your preferred area or try a larger one if you wish
• Extract the desired rar file to a convenient location on your PC to obtain gmapbmap.rgn & Updater.exe
• Drag gmapbmap.rgn onto Updater.exe
• Connect your unit to PC
• Select the appropriate connection on Updater's GUI and press OK to flash when unit is detected (some devices will need to be connected to a power source)
• Don't interrupt the flash or your unit may brick
• Your current basemap will be overwritten provided the unit's region 3 has sufficient space for the new basemap

If you receive an error message such as the following from Updater.exe when trying to flash a basemap larger than your existing, then your device probably has insufficient room for the intended one and you'll need to flash a smaller map:

[Only registered and activated users can see links. ]

If you do receive that message, disconnect and check the device. Even though it may show the new basemap details on the start-up screen you'll still need to check if the basemap is present by zooming out on the Map screen and browsing around. Probably it's missing entirely and you'll need to flash a smaller one. [For instance: Atlantic V3 is a full basemap and at 12,816 KB may not fit on your device, however V2 is a Recreational Basemap and at 6,604 KB should fit].

2. If you want to create an rgn file from a different basemap here's how:
Either do (a) or (b).
(a):

• Change the extension name of the selected gmapbmap.img file to gmapbmap.bin
• Open gmapbmap.bin in RGN_Tool
• Save as gmapbmap.rgn
• Open gmapbmap.rgn in a hex editor
• Search for 'R' in plain text or '52 33' in hexadecimal, typically R is at offset 0x31
• Change 33 to 03 [at offset 0x32 typically]
• Save the changes and then flash using Updater.exe as detailed in Tutorial 1 above.

(b):

• Change the extension name of the selected gmapbmap.img file to gmapbmap.bin
• Copy the following 60 byte hexstring to the PC's clipboard:
  Code:

  Please Login or Register to see the links

  Note that the above string is only correct for making an RGN to flash a basemap to region 3. If you wish to make an RGN for a detail map then look for "52 03" in the string and change "03" to the desired region, for example "0A" for region 10 (Supplementary detail map) or "31" for region 49 (Primary detail map)
• Open gmapbmap.bin in a hex editor and paste the string at the start of the file
• Save as gmapbmap.rgn then flash it using Updater.exe as detailed in Tutorial 1 above.

EDIT: There's an easier way, look at Post #3 for makergn.exe use to automate and simplify the process of converting an img file to an rgn file. Thanks to kunix.

DISCLAIMER: All flashing carries some risk. You alone must accept all risk and make an informed assessment as to whether you have the necessary knowledge to do the above tasks. If you don't understand or are uncomfortable doing it, don't do anything until you are.