汇编实现流水灯

1.使能时钟：

	@1使能GPIO的外设时钟
    ldr r0,=0x50000A28
    ldr r1,[r0]
    orr r1,r1,#(0x3<<4)//使能第４，５位
    str r1,[r0]

2.设置为输出模式

@设置GPIOE10为输出模式
    ldr r0,=0x50006000
    ldr r1,[r0]
    bic r1,r1,#(0x3<<20)
    orr r1,r1,#(0x1<<20)
    str r1,[r0]
    @GPIOE8
	ldr r0,=0x50006000
    ldr r1,[r0]
    bic r1,r1,#(0x3<<16)
    orr r1,r1,#(0x1<<16)
    str r1,[r0]
	@GPIOF10
	ldr r0,=0x50007000
    ldr r1,[r0]
    bic r1,r1,#(0x3<<20)
    orr r1,r1,#(0x1<<20)
    str r1,[r0]
 

3.设置为推挽输出

 @设置PE10为推挽输出
    ldr r0,=0x50006004
    ldr r1,[r0]
    bic r1,r1,#(0x1<<10)
    str r1,[r0]
 
	ldr r0,=0x50007004
    ldr r1,[r0]
    bic r1,r1,#(0x1<<10)
    str r1,[r0]
 
	ldr r0,=0x50006004
    ldr r1,[r0]
    bic r1,r1,#(0x1<<8)
    str r1,[r0]

4.设置为低速输出

@设置PE10为低速输出
    ldr r0,=0x50006008
    ldr r1,[r0]
    bic r1,r1,#(0x3<<20)
    str r1,[r0]
 
	ldr r0,=0x50006008
    ldr r1,[r0]
    bic r1,r1,#(0x3<<16)
    str r1,[r0]
 @GPIOF10
	ldr r0,=0x50007008
    ldr r1,[r0]
    bic r1,r1,#(0x3<<20)
    str r1,[r0]

5封装开关灯指令

light1_off:
	ldr r0,=0x50006014
    ldr r1,[r0]
    bic r1,r1,#(0x1<<10)
    str r1,[r0] 
	mov pc,lr
 
light2_up:
    @点亮灯
    ldr r0,=0x50006014
    ldr r1,[r0]
    orr r1,r1,#(0x1<<8)
    str r1,[r0] 
	mov pc,lr
light2_off:
	ldr r0,=0x50006014
    ldr r1,[r0]
    bic r1,r1,#(0x1<<8)
    str r1,[r0] 
	mov pc,lr
 
light3_up:
    @点亮灯
    ldr r0,=0x50007014
    ldr r1,[r0]
    orr r1,r1,#(0x1<<10)
    str r1,[r0] 
	mov pc,lr
light3_off:
	ldr r0,=0x50007014
    ldr r1,[r0]
    bic r1,r1,#(0x1<<10)
    str r1,[r0] 
	mov pc,lr

6封装delay

delay:
	ldr r3,=0x10000000
delay1:
	cmp r3,#0
	subne r3,r3,#1
	bne delay1
	mov pc,lr

7.功能逻辑实现

bl loop
loop:
	bl light3_off
	bl light1_up
	bl delay
	bl light1_off
	bl light2_up
	bl delay
	bl light2_off
	bl light3_up
	bl delay
 
	b loop
.end