.section .startup
.code 32
+startup:
ldr sp, =_stacktop
- mov r0, #1
+ mov r0, #2
bl dbgled
@ clear bss
mov r0, #0
bl dbgled
-halt: wfe
- b halt
+ .global exit
+exit: wfe
+ b exit
+ .global dbgled
dbgled:
ldr r3, =0x3f200000 @ gpio base
ldr r2, =0x9000 @ gpio 24 and 25 -> output
str r2, [r3, #8] @ store to GPFSEL2
ldr r2, =0x01000000 @ bit 24
- teq r0, #0
- streq r2, [r3, #0x1c] @ GPSET0
- strne r2, [r3, #0x28] @ GPCLR0
+ tst r0, #1
+ strne r2, [r3, #0x1c] @ GPSET0
+ streq r2, [r3, #0x28] @ GPCLR0
lsl r2, #1
+ tst r0, #2
strne r2, [r3, #0x1c] @ GPSET0
streq r2, [r3, #0x28] @ GPCLR0
bx lr
+
@ vi:set filetype=armasm: