01 arm11 led 跑马灯程序

.text
.globl _start
_start:
        ldr r0, =0x70000000
        orr r0, r0, #0x13
        mcr p15, 0, r0, c15, c2, 4

        ldr r0, =0x7e004000
        mov r1, #0
        str r1, [r0]

        ldr sp, =8*1024
        bl xxxx

        b .

start.S文件代码；

 

void delay ()
{
	int i;

	for (i = 0; i < 100000; i++)
		;
}

int xxxx (void)
{
	volatile unsigned long *gpmcon = (volatile unsigned long *)0x7f008820;		volatile unsigned long *gpmdat = (volatile unsigned long *)0x7f008824;
	int i;

	for (i = 1; i <= 4; i++){
		if (1 == i){
			*gpmcon &= ~0xffff;
			*gpmcon |= 0x1;
		}else if (2 == i){
			*gpmcon &= ~0xffff;
			*gpmcon |= 0x10;
		}else if (3 == i){
			*gpmcon &= ~0xffff;
			*gpmcon |= 0x100;
		}else if (4 == i){
			*gpmcon &= ~0xffff;
			*gpmcon |= 0x1000;
			i = 0;
		}
		*gpmdat = 0;
		delay();
	}

	return 0;
}

led.c 文件代码；

all:start.o led.o
        arm-linux-ld -Ttext 0 -o led.elf start.o led.o
        arm-linux-objcopy -O binary led.elf led.bin
        arm-linux-objdump -D led.elf > led.dis
        cp led.bin /tftpboot/led.bin
start.o:
        arm-linux-gcc -c start.S -o start.o
led.o:
        arm-linux-gcc -c -o led.o led.c
clean:
        rm -rf *.o *.elf *.dis *.bin /tftpboot/*.bin

Makefile文件代码；