利用定时器和蜂鸣器唱歌
【实验目的】
学会利用单片机的定时器，掌握蜂鸣器的发声操作。
【实验现象】
用单片机的P2.3口输出不同占空比的方波来控制与它相连的蜂鸣器，当方波的占空比不同时蜂鸣器发出的音调就不同，由此根据歌曲的音调编程实现让蜂鸣器唱歌。
【实验说明】
占空比：一个周期中，高电平的长度比上总周期的长度的值再乘上100%。标准方波的占空比为50%。
【硬件电路】
【程序代码】（程序源码见附件，可自行下载使用）
#include <reg52.h>
//实验目的：学会利用单片机的定时器，掌握蜂鸣器的发声操作
//实验现象：用单片机的P2.3口输出不同占空比的方波来控制与它相连的蜂鸣器，
//当方波的占空比不同时蜂鸣器发出的音调就不同，由此根据歌曲的音调编程实现让蜂鸣器唱歌。
//占空比：一个周期中，高电平的长度比上总周期的长度的值再乘上100%。标准方波的占空比为50%。
sbit beep=P2^3; //蜂鸣器控制位
unsigned int num;
unsigned char code SONG[] =
{
//祝你平安，以下为编码
0x26,0x20,0x20,0x20,0x20,0x20,0x26,0x10,0x20,0x10,0x20,0x80,
0x26,0x20,0x30,0x20,0x30,0x20,0x39,0x10,0x30,0x10,0x30,0x80,
0x26,0x20,0x20,0x20,0x20,0x20,0x1c,0x20,0x20,0x80,0x2b,0x20,
0x26,0x20,0x20,0x20,0x2b,0x10,0x26,0x10,0x2b,0x80,0x26,0x20,
0x30,0x20,0x30,0x20,0x39,0x10,0x26,0x10,0x26,0x60,0x40,0x10,
0x39,0x10,0x26,0x20,0x30,0x20,0x30,0x20,0x39,0x10,0x26,0x10,
0x26,0x80,0x26,0x20,0x2b,0x10,0x2b,0x10,0x2b,0x20,0x30,0x10,
0x39,0x10,0x26,0x10,0x2b,0x10,0x2b,0x20,0x2b,0x40,0x40,0x20,
0x20,0x10,0x20,0x10,0x2b,0x10,0x26,0x30,0x30,0x80,0x18,0x20,
0x18,0x20,0x26,0x20,0x20,0x20,0x20,0x40,0x26,0x20,0x2b,0x20,
0x30,0x20,0x30,0x20,0x1c,0x20,0x20,0x20,0x20,0x80,0x1c,0x20,
0x1c,0x20,0x1c,0x20,0x30,0x20,0x30,0x60,0x39,0x10,0x30,0x10,
0x20,0x20,0x2b,0x10,0x26,0x10,0x2b,0x10,0x26,0x10,0x26,0x10,
0x2b,0x10,0x2b,0x80,0x18,0x20,0x18,0x20,0x26,0x20,0x20,0x20,
0x20,0x60,0x26,0x10,0x2b,0x20,0x30,0x20,0x30,0x20,0x1c,0x20,
0x20,0x20,0x20,0x80,0x26,0x20,0x30,0x10,0x30,0x10,0x30,0x20,
0x39,0x20,0x26,0x10,0x2b,0x10,0x2b,0x20,0x2b,0x40,0x40,0x10,
0x40,0x10,0x20,0x10,0x20,0x10,0x2b,0x10,0x26,0x30,0x30,0x80,0x00,
//路边的野华不要采 , 以下为这首歌的编码
0x30,0x1C,0x10,0x20,0x40,0x1C,0x10,0x18,0x10,0x20,0x10,0x1C,
0x10,0x18,0x40,0x1C,0x20,0x20,0x20,0x1C,0x20,0x18,0x20,0x20,
0x80,0xFF,0x20,0x30,0x1C,0x10,0x18,0x20,0x15,0x20,0x1C,0x20,
0x20,0x20,0x26,0x40,0x20,0x20,0x2B,0x20,0x26,0x20,0x20,0x20,
0x30,0x80,0xFF,0x20,0x20,0x1C,0x10,0x18,0x10,0x20,0x20,0x26,
0x20,0x2B,0x20,0x30,0x20,0x2B,0x40,0x20,0x20,0x1C,0x10,0x18,
0x10,0x20,0x20,0x26,0x20,0x2B,0x20,0x30,0x20,0x2B,0x40,0x20,
0x30,0x1C,0x10,0x18,0x20,0x15,0x20,0x1C,0x20,0x20,0x20,0x26,
0x40,0x20,0x20,0x2B,0x20,0x26,0x20,0x20,0x20,0x30,0x80,0x20,
0x30,0x1C,0x10,0x20,0x10,0x1C,0x10,0x20,0x20,0x26,0x20,0x2B,
0x20,0x30,0x20,0x2B,0x40,0x20,0x15,0x1F,0x05,0x20,0x10,0x1C,
0x10,0x20,0x20,0x26,0x20,0x2B,0x20,0x30,0x20,0x2B,0x40,0x20,
0x30,0x1C,0x10,0x18,0x20,0x15,0x20,0x1C,0x20,0x20,0x20,0x26,
0x40,0x20,0x20,0x2B,0x20,0x26,0x20,0x20,0x20,0x30,0x30,0x20,
0x30,0x1C,0x10,0x18,0x40,0x1C,0x20,0x20,0x20,0x26,0x40,0x13,
0x60,0x18,0x20,0x15,0x40,0x13,0x40,0x18,0x80,0x00,
};
void Time0_Init()
{
TMOD=0x01; //设置定时器0工作方式1
TH0=(65536-45872)/256; //装初值11.059M晶振定时50ms数为45872
//THX=(65536-N)/256 N=X(us)/H1(机器周期) H1=12*（1/晶振频率）
TL0=(65536-48572)%256;
EA=1; //开总中断
ET0=1; //开定时器0中断
}
void T0_time() interrupt 1
{
TH0=(65536-45872)/256; //装初值11.059M晶振定时50ms数为45872
//THX=(65536-N)/256 N=X(us)/H1(机器周期) H1=12*（1/晶振频率）
TL0=(65536-48572)%256;
num++;
}
/-------------------------------------------------
1MS 延时子程序
-------------------------------------------------/
void Delay_xMs(unsigned int x)
{
unsigned int i,j;
for( i =0;i < x;i++ )
{
for( j =0;j<3;j++ );
}
}
/-------------------------------------------------
功能:歌曲播放子程序 i 为播放哪一段曲目
-------------------------------------------------/
void Play_Song(unsigned char i)
{
unsigned char Temp1,Temp2;
unsigned int Addr;
num = 0; //中断计数器清 0
Addr = i * 217;
while(1)
{
Temp1 = SONG[Addr++];
if ( Temp1 == 0xFF ) //休止符
{
TR0 = 0;
Delay_xMs(100);
}
else if ( Temp1 == 0x00 ) //歌曲结束符
{
return;
}
else
{
Temp2 = SONG[Addr++];
TR0 = 1;
while(1)
{
beep = ~beep;
Delay_xMs(Temp1);
if ( Temp2 == num )
{
num = 0;
break;
}
}
}
}
}
/-------------------------------------------------
功能:主程序
-------------------------------------------------/
void main()
{
Time0_Init(); //定时器 0 中断初始化
while(1)
{
Play_Song(0); //播放
}
}
