led_statusset.s

ARM嵌入式系统关于IRQ中断处理基于c语言的实验代码

	IMPORT	led_dummyAddress
	IMPORT	ledStatusSetDelay

	IMPORT	gpio_GAFR2L
	IMPORT	gpio_GPSR2
	IMPORT	gpio_GPCR2
	IMPORT	initGpio_GAFR2L
	IMPORT	initGpio_GPDR2


	EXPORT	led_statusSet

	AREA led_statusSet ,CODE ,READONLY

	stmfd r13!,{r4,r5,r8-r11,r14}

	ldr r5,=initGpio_GPDR2
	ldr r8,=gpio_GAFR2L
	ldr r9,=gpio_GPSR2
	ldr r10,=gpio_GPCR2
	ldr r11,=led_dummyAddress

	mvn r0,r0
	and r0,r0,#0xff
	mov r4,#0x0
	str r4,[r8]

	ldr r4,=ledStatusSetDelay
setStatusLoop
	sub r4,r4,#0x1
	cmp r4,#0x0
	bne setStatusLoop




	str r0,[r11]
	nop
	str r5,[r10]
	str r5,[r9]

	nop
	nop
	ldr r4,=initGpio_GAFR2L
	str r4,[r8]
	nop
	nop
	ldmfd r13!,{r4,r5,r8-r11,pc}
	END