Thread: Garmin eTREX 20 working as an eTREX 30

I think, values at 0x12009000 are filled by the bootloader. Unfortunately, I've found no bootloader in the boot.bin. Can you dump the bootloader (region 5) as suggested below?
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Hello, in the boot there is the same function as in the firmware to identify the pattern of PCB. I think memory is a memory 0x12009000 own the pcb that identifies it.
When you access USB-boot mode, this routine displays the gps as eTREX20, since it is not patched. In normal power mode is shown as eTREX30, (Windows Explorer, Basecam, etc ...).
I pass the link of boot 2.80.[Only registered and activated users can see links. ]
Very interesting TXT file commands, will try to prove if I understand.

Boot: 0418491C sub_4598491C; CODE XREF: +16 sub_459849A2? P
Boot: 0418491C LDR R0, = 0x12009000
Boot: 0418491E PUSH {R4, LR}
Boot: 04184920 LDR R3, = 0x428003C
Boot: 04184922 LDR R2, [R0, # 0x20]
Boot: 04184924 MOVS R1, 0x1E0000
Boot: 04184928 Orrs R2, R1
Boot: 0418492A STR R2, [R0, # 0x20]
Boot: 0418492C LDR R2, [R0, # 0x24]
Boot: 0418492E BICS R2, R1
Boot: 04184930 STR R2, [R0, # 0x24]
Boot: 04184932 LDR R0, [R0]
Boot: 04184934 LSLS R0, R0, # 0xB
Boot: 04184936 LSRs R0, R0, # 0x1C
Boot: 04184938 STRB R0, [R3]
Boot: 0418493A LDRB R0, [R3]
Boot: 0418493C STRB R0, [R3, # 1]
Boot: 0418493E BL sub_4599380A
Boot: 04184942 POP {R4, PC}
Boot: 04184942; End of function sub_4598491C

0x12009000 is just RAM, as it's writable.

I've extracted the boot.bin and found that function at 0x0418491C. But I'm not talking about boot.bin. I'm talking about the bootloader, which is not boot.bin. Bootloader is stored inside flash region number 5. Put rrgn,5,1:/5.bin into update.txt to dump it.
Those names boot.bin and fw_all.bin are quite bad, they don't reflect the real things.

hi, i test update.txt in /garmin/update.txt, /garmin/Updater/update.txt, sd:/garmin/update.txt, sd:/garmin/Updater/update.txt and it not write "5.bin".

How many regions have the GPS, when it is updating it show erase and writing in region 14.

You should create the following files:
sd:/Garmin/Updater/1305/update.txt (make sure it has one byte per character (ANSI encoding, not UNICODE))
sd:/Garmin/Updater/1305/ldr.bin (it's just renamed boot.bin)

The following files should be created after update.txt execution in case of success:
sd:/Garmin/Updater/1305/update.log
sd:/Garmin/Updater/1305/last_id.bin
sd:/5.bin