一、声光报警器

#include <REG51.H>

void delay(unsigned int i);

sbit S1=P0^0;
sbit beep=P1^0;
sbit red=P1^2;
sbit green=P1^1;

void main()
{
	green=0;
	red=1;
	while(1)
	{
	if(S1==0)
		{
	delay(1200);
			if(S1==0)
			{
				green=1;
				red=0;
				beep=0;
				delay(5000);
				red=1;
				beep=1;
			}
	}
		else green=0;
	}
}
void delay(unsigned int i)
{
	unsigned int k;
	for(k=0;k<i;k++);
}

二、一直报警

#include <REG51.H>

void delay(unsigned int i);

sbit S1=P0^0;
sbit beep=P1^0;
sbit red=P1^2;
sbit green=P1^1;

void main()
{
	green=0;
	red=1;
	while(1)
	{
	if(S1==0)
		{
	delay(1200);
			if(S1==0)
				while(1)
			{
				green=1;
				red=0;
				beep=0;
				delay(5000);
				red=1;
				beep=1;
				delay(1200);
			}
	}
		else green=0;
	}
}
void delay(unsigned int i)
{
	unsigned int k;
	for(k=0;k<i;k++);
}

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链接：https://pan.baidu.com/s/1wV6i-nDFsJw0882sDD-ung 
提取码：2222