单片机蜂鸣器代码

我用的蜂鸣器固定的控制端口是P1.5这个端口
蜂鸣器必须通过脉冲来实现发声

//最简单的蜂鸣器发声代码:
#include
#include
sbit beep=P1^5;
typedef unsigned int u16;
typedef unsigned char u8;

void delay(u16 i)
{
     
	while(i--);
}
void main()
{
     
	while(1)
	{
     
		 beep=~beep;//变化来实现一个脉冲
		 delay(100);//延迟程序来控制脉冲的频率，以达到不同的声音
	}	
} 

用蜂鸣器来播放一首歌曲《两只老虎》:

#include 
#define RldTmr(fr) 65536 - (11059200 / 12) / (fr << 1)
#define FuDian(n) (n << 1) / 3    //附点n分音符的换算
 
typedef unsigned char UCHAR;
typedef unsigned int UINT;
typedef unsigned long ULONG;
 
sbit BUZZ = P1^5;
 
UINT code noteFreq[] = {
         //中音 1-7 和高音 1-7对应的频率列表
    523, 587, 659, 698, 784, 880, 988,
    1047, 1175, 1319, 1397, 1568, 1760, 1976
};
UINT code tmrRld[] = {
           //中音 1-7 和高音 1-7对应的定时器重载值
    RldTmr(523), RldTmr(587), RldTmr(659), RldTmr(698), RldTmr(784), RldTmr(880), RldTmr(988),
    RldTmr(1047), RldTmr(1175), RldTmr(1319), RldTmr(1397), RldTmr(1568), RldTmr(1760), RldTmr(1976),
};
UCHAR code musicNote[] = {
           //音名
    1, 2, 3, 1,
    1, 2, 3, 1,
    3, 4, 5,
    3, 4, 5,
    5, 6, 5, 4, 3, 1,
    5, 6, 5, 4, 3, 1,
    1, 5, 1,
    1, 5, 1
};
UCHAR code noteDuration[] = {
            //音名对应的时值，4表示4分音符，8表示8分音符，16表示16分音符
    4, 4, 4, 4,
    4, 4, 4, 4,
    4, 4, 2,
    4, 4, 2,
    FuDian(8), 16, FuDian(8), 16, 4, 4,
    FuDian(8), 16, FuDian(8), 16, 4, 4,
    4, 4, 2,
    4, 4, 2
};
bit enable = 1, tmrFlg = 0;
UCHAR T0RH = 0XFF, T0RL = 0X00;
 
void Delay(UINT n);
void PlayMusic(UCHAR speed);    //固定标准为4分音符的速度：例如speed = 108 表示一分钟扫过108个4分音符
 
void main() {
     
    EA = 1;
    TMOD = 0X01;
    TH0 = T0RH;
    TL0 = T0RL;
    ET0 = 1;
    TR0 = 1;
    while (1) {
     
        PlayMusic(72);
        Delay(40000u);
    }
}
 
void Delay(UINT n) {
     
    UINT i;
    for (i = 0; i < n; i++) ;
}
 
void PlayMusic(UCHAR speed) {
     
    UCHAR i;
    UCHAR idx;
    UINT cnt = 0;
    UINT durationCnt = 0;	//当前音符的时值对应的定时器计数
    UINT soundCnt = 0;		//当前音符的发声时值对应的计数值
    for (i = 0; i < sizeof (musicNote); ) {
     
        while (!tmrFlg) ;
        tmrFlg = 0;
        if (cnt == 0) {
     
            idx = musicNote[i] - 1;
            T0RH = tmrRld[idx] >> 8;
            T0RL = tmrRld[idx];
            durationCnt = (ULONG)240 * (ULONG)noteFreq[idx] / ((ULONG)noteDuration[i] * (ULONG)speed);
            soundCnt = durationCnt - (durationCnt >> 2);	//当前音符时值的前3/4发声，后1/4静音
            enable = 1;
            cnt++;
        }
        else {
     
            if (cnt == durationCnt) {
     
                cnt = 0;
                i++;
            }
            else {
     
                cnt++;
                if (cnt == soundCnt) {
     
                    enable = 0;
                }
            }
        }
    }
}
 
void InterruptTmr0() interrupt 1 {
     
    TH0 = T0RH;
    TL0 = T0RL;
    tmrFlg = 1;
    if (enable)
        BUZZ = ~BUZZ;
    else
        BUZZ = 1;
}

上面这段代码的原码 点击这里访问