ARM笔记: GPIO口LED程序

leds.bin:crt0.S    leds.c
    arm-linux-gcc -g -c -o crt0.o crt0.S
    arm-linux-gcc -g -c -o leds.o leds.c
    arm-linux-ld -Ttext 0x00000000 -g crt0.o leds.o -o leds_elf
    arm-linux-objcopy -O binary -S leds_elf leds.bin
    arm-linux-objdump -D -m arm leds_elf>leds.dis
clean:
    rm -f leds.dis leds.bin leds_elf *.o


.text
.global _start
_start:
    ldr     r0,=0x56000010
    mov    r1,#0x0
    str    r1,[r0]
   
    ldr    sp,=1024*4
   
    bl    main
halt_loop:   
    b     halt_loop;


#define GPFCON    (*(volatile unsigned long *)0x56000050)
#define GPFDAT    (*(volatile unsigned long *)0x56000054)

#define GPF4_OUT    (1<<(4*2))    //dfjlf
#define GPF5_OUT    (1<<(5*2))
#define GPF6_OUT    (1<<(6*2))

void Delay(volatile unsigned long dly)
{
    for(;dly>0;dly--);
}

int main(void)
{
    unsigned long i=4;
    GPFCON=GPF4_OUT|GPF5_OUT|GPF6_OUT;
    GPFDAT=0x11111111;
    while(1)
    {
        GPFDAT=~(1<        Delay(10000);       
        i++;
        if(i==7)
        i=4;       
    }
    return 0;
}