微處理器 - Nuvoton NUC972 - Assembly - GPIO(IRQ)

參考資訊：
https://github.com/OpenNuvoton/NUC970_NonOS_BSP

GPIO Interrupt = 57


AIC Mask


GPIOB_IFEN


Clear


main.s

    .equ GPIOB_DIR,     (0xb8003000 + 0x40)
    .equ GPIOB_DATAOUT, (0xb8003000 + 0x44)
    .equ GPIOB_DATAIN,  (0xb8003000 + 0x48)
    .equ GPIOB_IFEN,    (0xb8003000 + 0x54)
    .equ GPIOB_PUEN,    (0xb8003000 + 0x60)
    .equ CLK_PCLKEN0,   (0xb0000200 + 0x18)
    .equ AIC_MECR,      (0xb8002000 + 0x130)
    .equ AIC_MECRH,     (0xb8002000 + 0x134)
    .equ AIC_EOSCR,     (0xb8002000 + 0x150)

    .text
    .align 2
    .global _start
_start:    b reset
_undef:    b .
_swi:      b .
_pabort:   b .
_dabort:   b .
_reserved: b .
_irq:      b irq_handler
_fiq:      b .
 
reset:
    mrs r0, cpsr
    bic r0, #0x80
    msr cpsr_c, r0
 
    ldr r0, =AIC_MECRH
    ldr r1, =(1 << (57 - 32))
    str r1, [r0]
    
    ldr r0, =CLK_PCLKEN0
    ldr r1, [r0]
    orr r1, #(1 << 3)
    str r1, [r0]
    
    ldr r0, =GPIOB_DIR
    ldr r1, =(1 << 0)
    str r1, [r0]
        
    ldr r0, =GPIOB_PUEN
    ldr r1, =(1 << 1)
    str r1, [r0]
        
    ldr r0, =GPIOB_IFEN
    ldr r1, =(1 << 1)
    str r1, [r0]
        
    ldr r0, =GPIOB_DATAOUT
    ldr r1, =(1 << 0)
    str r1, [r0]
    b .
 
irq_handler:
    ldr r0, =GPIOB_DATAOUT
    ldr r1, =~(1 << 0)
    str r1, [r0]
    ldr r0, =AIC_EOSCR
    ldr r1, =1
    str r1, [r0]
    subs pc, lr, #4
    .end

完成