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.section ".text"
.globl uart_init
uart_init:
//*UART0_IMSC = 1 << 4;
mov r2, #0x1038
movt r2, #0x3F20
mov r3, #0b10000
str r3, [r2]
//*IRQ_ENABLE2 = 1 << 25;
mov r2, #0xB214
movt r2, #0x3F00
mov r3, #0
movt r3, #0b1000000000
str r3, [r2]
//*GPU_INTERRUPTS_ROUTING = 0x00;
mov r2, #0x000C
movt r2, #0x4000
eor r3, r3
str r3, [r2]
bx lr
.globl uart_char
uart_char:
mov r2, #0x1000
movt r2, #0x3f20
uart_char.loop:
ldr r3, [r2, #24]
tst r3, #0b100000
bne uart_char.loop
str r0, [r2]
bx lr
.globl uart_string
uart_string:
push {r4, lr}
mov r4, r0
ldrb r0, [r0]
cmp r0, #0
popeq {r4, pc}
uart_string.loop:
bl uart_char
ldrb r0, [r4, #1]!
cmp r0, #0
bne uart_string.loop
pop {r4, pc}
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