#include<reg52.h>
#define uint unsigned int
#define uchar unsigned char

sbit BEEP=P0^0;

uchar th0_f,tl0_f;
uchar data diaodata[30]; //音調(diào)緩沖
uchar data jiedata[30];  //音長緩沖
//T0的值,及輸出頻率對照表
uchar code freq[36*2]={
	0xA9,0xEF,//00220HZ ,1	 //0
	0x93,0xF0,//00233HZ ,1#
	0x73,0xF1,//00247HZ ,2
	0x49,0xF2,//00262HZ ,2#
	0x07,0xF3,//00277HZ ,3
	0xC8,0xF3,//00294HZ ,4
	0x73,0xF4,//00311HZ ,4#
	0x1E,0xF5,//00330HZ ,5 
	0xB6,0xF5,//00349HZ ,5#
	0x4C,0xF6,//00370HZ ,6
	0xD7,0xF6,//00392HZ ,6#
	0x5A,0xF7,//00415HZ ,7    
	0xD8,0xF7,//00440HZ 1     //12
	0x4D,0xF8,//00466HZ 1#    //13
	0xBD,0xF8,//00494HZ 2     //14
	0x24,0xF9,//00523HZ 2#    //15
	0x87,0xF9,//00554HZ 3     //16
	0xE4,0xF9,//00587HZ 4     //17
	0x3D,0xFA,//00622HZ 4#    //18
	0x90,0xFA,//00659HZ 5     //19
	0xDE,0xFA,//00698HZ 5#    //20
	0x29,0xFB,//00740HZ 6     //21
	0x6F,0xFB,//00784HZ 6#    //22
	0xB1,0xFB,//00831HZ 7     //23
	0xEF,0xFB,//00880HZ `1
	0x2A,0xFC,//00932HZ `1#
	0x62,0xFC,//00988HZ `2
	0x95,0xFC,//01046HZ `2#
	0xC7,0xFC,//01109HZ `3
	0xF6,0xFC,//01175HZ `4
	0x22,0xFD,//01244HZ  `4#
	0x4B,0xFD,//01318HZ `5
	0x73,0xFD,//01397HZ `5#
	0x98,0xFD,//01480HZ `6
	0xBB,0xFD,//01568HZ `6#
	0xDC,0xFD,//01661HZ `7	   //35
};

//=============================
void timer1() interrupt 3 using 3 //用于產(chǎn)生唱歌頻率
{
    TL1=tl0_f;TH1=th0_f;  //調(diào)入預(yù)定時值
    BEEP=~BEEP;           //取反音樂輸出I/O
}

//******************************
//音樂符號串解釋函數(shù)
//入口:要解釋的音樂符號串,輸出的音調(diào)串,輸出的時長串
void changedata(uchar *song,uchar *diao,uchar *jie)
{
    uchar i,i1,j;
    char gaodi; //高低+/-12音階
    uchar banyin;//有沒有半個升音階
    uchar yinchang;//音長
    uchar code jie7[8]={0,12,14,16,17,19,21,23}; //C調(diào)的7個值

    *diao=*song;
    for(i=0,i1=0;;)
    {
        gaodi=0; //高低=0
        banyin=0;//半音=0
        yinchang=4;//音長1拍
        if((*(song+i)=='|') || (*(song+i)==' ')) i++; 
		//拍子間隔和一個空格過濾

        switch(*(song+i)) 
        {    
            case ',': gaodi=-12;i++;//低音
            break;
    
            case '`': gaodi=12;i++; //高音
            break;
        }

        if(*(song+i)==0)  //遇到0結(jié)束
        {
            *(diao+i1)=0; //加入結(jié)束標志0
            *(jie+i1)=0;
            return;
        }

        j=*(song+i)-0x30; i++; //取出基準音
        j=jie7[j]+gaodi; //加上高低音
						

yinc:   switch(*(song+i)) 
        {    
            case '#': //有半音j加一個音階 
                i++;j++;
				goto yinc; 
            

            case '-': //有一個音節(jié)加長
                yinchang+=4;
                i++; 
                goto yinc;

            case '_': //有一個音節(jié)縮短
                yinchang/=2;
                i++; 
				goto yinc;
            
            
            case '.': //有一個加半拍
                yinchang=yinchang+yinchang/2;
				i++;
				goto yinc;
            
        }

        *(diao+i1)=j;       //記錄音符
        *(jie+i1)=yinchang; //記錄音長
        i1++;    

    }
}

//******************************************
//奏樂函數(shù)
//入口:要演奏的音樂符號串
void play(uchar *songdata)
{
    uchar i,c,j=0;
    uint  n;
    
    changedata(songdata,diaodata,jiedata); //解釋音樂符號串
    for(i=0;diaodata[i]!=0;i++)  //逐個符號演奏
    {
        tl0_f=freq[diaodata[i]*2]; //取出對應(yīng)的定時值送給T0
        th0_f=freq[diaodata[i]*2+1];
        TR1=1;      
        for(c=0;c<jiedata[i];c++) //按照音長延時
		{
              for(n=0;n<25000;n++);
              
		}
        TR1=0;
        for(n=0;n<500;n++);    //音符間延時
    }
    TR1=0;
}