Thread: Garmin eTREX 20 working as an eTREX 30

It's always hard to disassemble GUI code, as it's huge and messy. Also I've tried to start from GCD parsing algorithm but found nothing.
I think AlexWhiter's advices are good. The following place seems to be the only one where SWVR is tested for being less or more than some integer. Also there is a reference to GUPDATE string in the BLS branch. So try to replace BLS at 0x80113B50 with B and replace BNE at 0x80113B6A with B and see what happens.

Code:

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UPD:
And, actually, there is a connection with GCD parsing code: 0x80113BA8 -> sub_801136A2 -> sub_8029D7D4 -> sub_801B9D60.
sub_801B9D60 is a GCD parsing and flashing routine.