(gdb)target remote localhost:3333

(gdb)monitor reset halt

(gdb)load

(gdb)continue

(gdb)stepi

...

const1: .word 0x40020400    @@GPIOB base mode register

const2: .word 0x55555555

const3: .word 0x40020414    @@GPIOB base output register

const4: .word 0x0000FFFF

...
...
...

reset_handler:

    ldr r0, =const2
    ldr r2, [r0]    @r2=const2
    ldr r0, =const1
    ldr r1, [r0]    @r1=const1
    str r2, [r1]                    @@set mode to output

    ldr r0, =const4
    ldr r2, [r0]    @r2=const4
    ldr r0, =const3
    ldr r1, [r0]    @r1=const3
    str r2, [r1]                    @@set output register to 1

loop:
b loop