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.syntax unified
.cpu cortex-m0plus
.thumb
.equ SRAM_BASE, 0x20000000
.type octedit, %function
.global octedit
octedit:
ldr r6, =SRAM_BASE
adds r5, r6, 1
10:
movs r4, 11
movs r0, 0x1E
rors r6, r0
movs r0, 0x01
b 1f
0:
movs r0, 0x1D
rors r6, r0
movs r0, 0x07
1:
ands r0, r6
adds r0, 0x30
bl uart_send
subs r4, 1
bne 0b
movs r0, '
bl uart_send
20:
bl uart_recv
cmp r0, '\r
bne 30f
bl uart_send
movs r0, '\n
bl uart_send
strh r4, [r6]
adds r6, 2
b 10b
30:
cmp r0, 'G
bne 40f
bx r5
40:
cmp r0, 'B
bne 50f
movs r0, '\r
bl uart_send
subs r6, 2
b 10b
50:
bl uart_send
subs r0, '0
lsls r4, 3
adds r4, r0
b 20b
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