Thread: Dakota 20 firmware study

ataro1, yes, you've got a boot.bin which simply doesn't flash regions 5 and 43. Obviously, they were flashed in factory and have never changed since then. It's still possible that Garmin will some day release boot.bin which would update regions 5 and 43.
Take a boot.bin from say nuvi 55 and you will find bootloader and x-loader copies inside it. Also you will find some function which references those copies and also contains proper region number constants.

Code:

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I think putting x-loader and bootloader inside boot.bin is a good idea, as it makes the x-loader and bootloader flashing procedure atomic.
I.e., either boot.bin executes correctly and flashes x-loader and bootloader, or boot.bin fails and flashes nothing.
Also I think it's a pretty standard practice in embedded systems world.
As an example of a non-atomic procedure, imagine you're flashing bootloader over USB and USB connection fails. So bootloader is corrupt and it will never boot again most probably.

Originally Posted by kunix

ataro1, yes, you've got a boot.bin which simply doesn't flash regions 5 and 43. Obviously, they were flashed in factory and have never changed since then. It's still possible that Garmin will some day release boot.bin which would update regions 5 and 43.
Take a boot.bin from say nuvi 55 and you will find bootloader and x-loader copies inside it. Also you will find some function which references those copies and also contains proper region number constants.

Code:

Please Login or Register to see the links

I think putting x-loader and bootloader inside boot.bin is a good idea, as it makes the x-loader and bootloader flashing procedure atomic.
I.e., either boot.bin executes correctly and flashes x-loader and bootloader, or boot.bin fails and flashes nothing.
Also I think it's a pretty standard practice in embedded systems world.
As an example of a non-atomic procedure, imagine you're flashing bootloader over USB and USB connection fails. So bootloader is corrupt and it will never boot again most probably.

I hope that in the future i don't have never the needs to flash 5 and 43. In the case, what do you say, the SD procedure with xrgn is safer respect the usb preboot?

I can definitely state that in Dakota are present only the followings rgn numbers: 5, 14, 15, 16, 34, 41, 43, 45, 86.
I've tested the full range of rgn numbers between 0 and 255 (>256 results all errors).