51单片机的一个IO口控制speaker发声

51单片机的一个I/O口控制speaker发声，演奏老鼠爱大米。

主要器件以及电路图
单片机——AT89C51，蜂鸣器——speaker。

C语言程序源码
C语言的程序代码更好读一些，相比较前面两个汇编的蜂鸣器程序，这个程序比较好理解。

/* 蜂鸣器--蜂鸣器奏乐-老鼠爱大米*/
#include
#define uint unsigned int
#define uchar unsigned char
#define ulong unsigned long
sbit beep=P2^7; //蜂鸣器输出引脚
uchar th0_f; //中断装载T0高8位
uchar tl0_f; //T0低8位
uchar code freq[36*2]={ //音阶码表0xf7,0xd8, //440hz , 1 //0
0xf8,0x50, //466hz , 1# //1
0xf8,0xbc, //494hz , 2 //2
0xf9,0x26, //524hz , 2# //3
0xf9,0x85, //554hz , 3 //4
0xf9,0xe5, //588hz , 4 //5
0xfa,0x3d, //622hz , 4# //6
0xfa,0x92, //660hz , 5 //7
0xfa,0xdd, //698hz , 5# //8
0xfb,0x29, //740hz , 6 //9
0xfb,0x70, //784hz , 6# //10
0xfb,0xb0, //830hz , 7 //11
0xfb,0xef, //880hz , 1 //12
0xfc,0x29, //932hz , 1# //13
0xfc,0x62, //988hz , 2 //14
0xfc,0x95, //1046hz, 2# //15
0xfc,0xc7, //1108hz, 3 //16
0xfc,0xf5, //1174hz, 4 //17
0xfd,0x20, //1244hz, 4# //18
0xfd,0x4c, //1318hz, 5 //19
0xfd,0x72, //1396hz, 5# //20
0xfd,0x97, //1480hz, 6 //21
0xfd,0xbb, //1568hz, 6# //22
0xfd,0xdc, //1662hz, 7 //23
0xfd,0xfb, //1769hz, `1 //24
0xfe,0x18, //1864hz, `1# //25
0xfe,0x34, //1976hz, `2 //26
0xfe,0x4e, //2092hz, `2# //27
0xfe,0x67, //2218hz, `3 //28
0xfe,0x7d, //2350hz, `4 //29
0xfe,0x94, //2488hz, `4# //30
0xfe,0xa8, //2639hz, `5 //31
0xfe,0xbc, //2794hz, `5# //32
0xfe,0xcf, //2960hz, `6 //33
0xfe,0xe0, //3136hz, `6# //34
0xfe,0xf1, //3322hz, `7 //35
};
uchar code diaodata[30]={ //音调代码0x10,0x0e,0x0c,0x10,0x0e,0x0c,
0x10,0x0e,0x10,0x0c,0x10,0x15,
0x13,0x10,0x13,0x15,0x15,0x13,
0x15,0x13,0x10,0x0e,0x0c,0x0e,
0x0e,0x10,0x0e,0x0c,0x0e,0x00};
uchar code jiedata[30]={ //音长代码0x04,0x04,0x08,0x06,0x02,0x08,
0x04,0x04,0x04,0x04,0x02,0x06,
0x08,0x02,0x02,0x04,0x04,0x04,
0x04,0x08,0x02,0x02,0x04,0x04,
0x02,0x02,0x04,0x04,0x0c,0x00};
void timer0() interrupt 1 //用于产生音符的T0中断服务程序{
TH0=th0_f;
TL0=tl0_f;
beep=~beep; //取反beep引脚，发声
}
void main(void)
{
uchar i,j,k=0;
uint n;
TMOD=0X01; //T0方式1
TR0=0; //关闭T0（不发声）
ET0=1; //允许T0中断
EA=1; //允许总中断
while(1)
{
TR0=1; //开T0
for(i=0;diaodata[i]!=0;i++)
{
th0_f=freq[diaodata[i]*2];
tl0_f=freq[diaodata[i]*2+1];
for(j=0;j<20000;n++); //(jiedata*20000) TR0=0;
for(n=0;n<256;n++); //音符之间的短暂延时
TR0=1;
}
TR0=0;
}
}。