[mkgmap-dev] OT: Edge 705 firmware hacking

Fri Jun 3 10:55:50 BST 2016

Hi Roger,

On Wed, Jun 01, 2016 at 08:09:45AM -0400, Roger Stevenson wrote:
>I have been having issues with my Garmin Edge 705 seeing the map SD 
>card and was hoping i could get copied of on older GCD file.

In the time frame when I had the 705, I do not remember experiencing 
that kind of trouble. Maybe once or twice the map would just disappear 
suddenly.

There were clear bugs in the conversion of recorded traces from the 
hidden internal format to the FAT file system in the internal memory.  
The bugs would slightly change between firmware updates, but never get 
fixed.

>I’ve been reading that downgrading then upgrading might take care of 
>issue with the 705.

If the issue is some corruption of an internal database, maybe a factory 
reset (hold Mode while powering up) would help? I remember that the list 
of recently searched places would appear corrupted whenever the map was 
updated. Maybe it will get too corrupted if the gmapsupp.img is updated 
sufficiently many times?

If the issue is dirt, have you tried taking apart the Edge 705 to clean 
the contacts of the card slot? You should only need a Torx screwdriver.  
If I remember correctly, there is something attached with a cable to the 
back cover. Maybe it was the battery or the SD card slot. No soldering 
should be needed.

>Would it be possible to get the file 3468836 Edge605_705_310.gcd from 
>you?

I still have the files, but I cannot guarantee that they did not get 
spontaneously corrupted, because I did not store any checksums 
separately. I have expericenced spontaneous corruption a few times for 
photos that had not been accessed for years.

	Marko