2、8个二极管来回亮，每次亮蜂鸣器滴滴两声；

#include<reg52.h>

#include<intrins.h>

#define uint unsigned int

#define uchar unsigned char

uint x,y,z;

uchar temp;

sbit b=P2^3;

void delay(uint);

void main()

{

temp=0xfe;

P1=temp;

while(1)

{

b=0;

delay(100);

b=1;

delay(100);

b=0;

delay(100);

b=1;

delay(620);

temp=_crol_(temp,1);

P1=temp;

}

}

void delay(uint z)

{

for(x=z;x>0;x--)

for(y=100;y>0;y--);

}