0任务要求: LEDO ~ LED7经限流电阻分别接至P1口的P1.0~P1.7引脚.上，阳极共同接高电平。实现高低四个LED交替点亮的代码

#include <reg52.h>

sbit LED0 = P1^0;
sbit LED1 = P1^1;
sbit LED2 = P1^2;
sbit LED3 = P1^3;
sbit LED4 = P1^4;
sbit LED5 = P1^5;
sbit LED6 = P1^6;
sbit LED7 = P1^7;

void main()
{
    while(1)
    {
        LED0 = 1; //点亮LED0
        LED2 = 1; //点亮LED2
        LED1 = 0; //熄灭LED1
        LED3 = 0; //熄灭LED3
        LED4 = 0; //熄灭LED4
        LED5 = 0; //熄灭LED5
        LED6 = 0; //熄灭LED6
        LED7 = 0; //熄灭LED7
        delay(500); //延时500ms

        LED0 = 0; //熄灭LED0
        LED2 = 0; //熄灭LED2
        LED1 = 1; //点亮LED1
        LED3 = 1; //点亮LED3
        LED4 = 1; //点亮LED4
        LED5 = 1; //点亮LED5
        LED6 = 1; //点亮LED6
        LED7 = 1; //点亮LED7
        delay(500); //延时500ms
    }
}

//延时函数，单位ms
void delay(unsigned int ms)
{
    unsigned int i, j;
    for(i=0; i<ms; i++)
    {
        for(j=0; j<110; j++);
    }
}