蜂鸣器——清翔单片机（V3.0）

#include <reg52.h>
#include <intrins.h>

#define uint unsigned int
#define uchar unsigned char

sbit beep = P2^3;
uchar temp;

void delay(uint z)
{
    uint x,y;
    for(x = z;x > 0;x--)
        for(y = 114;y > 0;y--);
}

void main()
{
    temp = 0xf0;
    P1 = temp;
    delay(100);
    while(1)
    {
        temp = _crol_(temp,1);
        P1 = temp;
        beep = ~beep;
        delay(100);    
    }

}