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.include "constants/gba_constants.inc"
.syntax unified
.arm
Start: @ 8000000
b Init
.incbin "baserom.gba", 0x4, 0xBC
.arm
.align 2
Init: @ 80000C0
mov r0, #0x12
msr cpsr_cf, r0
ldr sp, sp_irq
mov r0, #0x1F
msr cpsr_cf, r0
ldr sp, sp_sys
ldr r1, =INTR_VECTOR
adr r0, IntrMain
str r0, [r1]
ldr r1, =0x800095C + 1
mov lr, pc
bx r1
b Init
sp_sys: .4byte IWRAM_END - 0x100
sp_irq: .4byte IWRAM_END - 0x60
.pool
.global IntrMain
IntrMain: @ 8000104
mov r3, REG_BASE
add r3, r3, OFFSET_REG_IE
ldr r2, [r3]
ldrh r1, [r3, OFFSET_REG_IME - OFFSET_REG_IE]
mrs r0, spsr
stmdb sp!, {r0-r3,lr}
mov r0, 1
strh r0, [r3, OFFSET_REG_IME - OFFSET_REG_IE]
and r1, r2, r2, lsr 16
mov r12, 0
ands r0, r1, INTR_FLAG_SERIAL
bne IntrMain_FoundIntr
add r12, r12, 4
ands r0, r1, INTR_FLAG_TIMER3
bne IntrMain_FoundIntr
add r12, r12, 4
ands r0, r1, INTR_FLAG_VBLANK
bne IntrMain_FoundIntr
add r12, r12, 4
ands r0, r1, INTR_FLAG_HBLANK
bne IntrMain_FoundIntr
add r12, r12, 4
ands r0, r1, INTR_FLAG_VCOUNT
bne IntrMain_FoundIntr
add r12, r12, 4
ands r0, r1, INTR_FLAG_TIMER0
bne IntrMain_FoundIntr
add r12, r12, 4
ands r0, r1, INTR_FLAG_TIMER1
bne IntrMain_FoundIntr
add r12, r12, 4
ands r0, r1, INTR_FLAG_TIMER2
bne IntrMain_FoundIntr
add r12, r12, 4
ands r0, r1, INTR_FLAG_DMA0
bne IntrMain_FoundIntr
add r12, r12, 4
ands r0, r1, INTR_FLAG_DMA1
bne IntrMain_FoundIntr
add r12, r12, 4
ands r0, r1, INTR_FLAG_DMA2
bne IntrMain_FoundIntr
add r12, r12, 4
ands r0, r1, INTR_FLAG_DMA3
bne IntrMain_FoundIntr
add r12, r12, 4
ands r0, r1, INTR_FLAG_KEYPAD
bne IntrMain_FoundIntr
add r12, r12, 4
ands r0, r1, INTR_FLAG_GAMEPAK
strbne r0, [r3, OFFSET_REG_SOUNDCNT_X - OFFSET_REG_IE]
bne . @ spin
IntrMain_FoundIntr: @ 80001D4
strh r0, [r3, OFFSET_REG_IF - OFFSET_REG_IE]
mov r1, INTR_FLAG_GAMEPAK | INTR_FLAG_TIMER3 | INTR_FLAG_SERIAL
bic r2, r2, r0
and r1, r1, r2
strh r1, [r3]
mrs r3, cpsr
bic r3, r3, PSR_I_BIT | PSR_F_BIT | PSR_MODE_MASK
orr r3, r3, PSR_SYS_MODE
msr cpsr_cf, r3
ldr r1, =gIntrTable
add r1, r1, r12
ldr r0, [r1]
stmdb sp!, {lr}
adr lr, IntrMain_RetAddr
bx r0
IntrMain_RetAddr: @ 8000210
ldmfd sp!, {lr}
mrs r3, cpsr
bic r3, r3, PSR_I_BIT | PSR_F_BIT | PSR_MODE_MASK
orr r3, r3, PSR_I_BIT | PSR_IRQ_MODE
msr cpsr_cf, r3
ldmfd sp!, {r0-r3,lr}
strh r2, [r3]
strh r1, [r3, OFFSET_REG_IME - OFFSET_REG_IE]
msr spsr_cf, r0
bx lr
.pool
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