Firmware downgrade for 721xs to recognize custom maps

**ferabella** · 8th June 2022, 12:52 PM

Originally Posted by Pigom

...Now I can't use my own marine charts anymore. I would like to go back to v 3.80 (the last one whitch is working) but I can't nowhere find it...

Same situation here

Originally Posted by Cnfhbr

@ferabella

For the GPSMAP 721 unit, there is no point in going back to the old firmware, just patching your custom map with GCCMaps0.0.3 is enough.

Could you please direct me to some procedure or topic showing how to do it? Any link would be excellent, i am starting search çing that right now anyway
Sounds promising
It is a map done with cgpsmapper originally

**Cnfhbr** · 8th June 2022, 02:06 PM

Originally Posted by ferabella

Could you please direct me to some procedure or topic showing how to do it? Any link would be excellent ...

For example:

Code:

Please Login or Register to see the links

**ferabella** · 10th June 2022, 10:00 AM

I have installed GCCMaps0.0.3 (from the link above in boote-forum) and Visual Basic 6 Runtime Files (from sourceforge)
I copy the .img that show "map format not admitted" in gccmaps directory.
I drop the *.img file over the gccmaps program and it says "File patched correctly" in some .img and

I07246EF: No need to patch the tile
I07246FA: No need to patch the tile

in another .img

The .img is in the same directory of the GCCMaps, i pick it and drop over the GCCMaps.exe and the messages appear but no change in file, modified date of file, like if nothing would have been doone to the .img

I copy the .img to sd and put it in 721 software firmware version 6.80, not 6.50 not 4.2. This is the last one that blocks returnning to old firmwares and maybe blocks gccmaps too.
Message "map format not admitted" appears again

What am i doing wrong?

It is correct i pick the file in the gccmaps directory as it were "modified" or should i pick it from other place?

May be that version 6.80 introduces new system to block the possibility to patch .img´s?

**Cnfhbr** · 10th June 2022, 03:20 PM

Originally Posted by ferabella

What am i doing wrong?

You can PM me your source custom map and the one supposedly patched by you, and I'll see what's wrong.

**kornynz** · 2nd March 2023, 11:23 PM

hi everyone.

Could someone please help me where i can get old firmware versions for gpsmap 557xs.
I am stuck on version 6.4 and it will not update.
something weird happening with device as after a factory reset when i make any changes and reboot device, it has forgotten all the changes.
I delete all the waypoints and after re-boot they are all back...
I want to try downgrade to older versions and try upgrade from there.
Could you point me to older version and maybe even version 6.50?
Thanks