dzq.c

简易c语言单片机电子琴

#include "reg51.h"
#define shumaguan P0                               //定义数码管段码输出	  
sbit LED =P1^1 ;
sbit SPK =P1^0  ;                                 //定义方波输出口

unsigned int tone1,tone2;
/*****标准音符表*****/
//用于使定时器初值变化以产生相应频率的定时
unsigned char code yinfu[]={0xfb,0xe9,      //Do
                              0xfc,0x5c,      //Re
                              0xfc,0xc1,      //Mi
                              0xfc,0xef,      //Fa
                              0xfd,0x45,      //So
                              0xfd,0x92,      //La
                              0xfd,0xd0,      //Si
                              0xfd,0xee,      //Do#
                              0x00,0x00     //音符之间的间隔，只要间隔时间小于65ms时，
                                                        //喇叭不会发出声音，用作拍子之间的短暂停顿     
};
 
/*****生日快乐歌音调表*****/
unsigned char code shengri_tone[]={   1,0,1,2,1,4,3,0,
                                   1,0,1,2,1,5,4,0,
                                               1,0,1,8,6,4,3,2,0,
                                               7,0,7,6,4,5,4,0       //0代表不发声，即停顿；数字即为音调
};
 
/*****生日快乐歌节拍表*****/
unsigned char code shengri_beat[]={   24,1,24,48,48,48,72,5,
                                   24,1,24,48,48,48,72,5,
                                               24,1,24,48,48,48,48,72,5,
                                              24,1,24,48,48,48,72,5    //节拍，即tone表各音调的延时
};
 
/*****自动演示音调表*****/
unsigned char code yanshi_tone[]={    1,0,2,0,3,0,4,0,5,0,6,0,7,0,8,0,
                                          8,0,7,0,6,0,5,0,4,0,3,0,2,0,1,0
};
 
/*****自动演示节拍表*****/
unsigned char code yanshi_beat[]={     48,1,48,1,48,1,48,1,48,1,48,1,48,1,48,2,
                                                             48,1,48,1,48,1,48,1,48,1,48,1,48,1,48,2
 
};
 
/*****15ms延时子程序，用于节拍*****/
void delay(void)
{
       unsigned char n=15;
       while(n--)
       {
              unsigned char i;
              for(i=0;i<125;i++);
       }
}
 
/*****定时器0初始化*****/
void initTimer(void)
{
      TMOD=0x01;                                    //定时器0，工作方式1;定时器1，工作方式1
      TH0=tone1;
      TL0=tone2;
}
 
/*****定时器0中断服务程序*****/
void timer0(void) interrupt 1
{
      TH0=tone1;
      TL0=tone2;
      SPK=~SPK;                                       //取反，以产生方波
}
 
/*****演奏子程序1*****/
void play1(void)
{
       unsigned char m=0;
       unsigned char s;     
       unsigned char a=1;
       while(1)
       {
              EA=0;
              LED=0;
              a=shengri_tone[m];                            //取音符
	      shumaguan=a;
              s=shengri_beat[m];                      //取节拍
              tone1=yinfu[2*a-2];                            
              tone2=yinfu[2*a-1];                            
              EA=1;
              while(s--)
              {
                     delay();
              }
              LED=1;
              m++;
              if(m>=33) return;                      //数值是shengri相关表中的元素数量  
       }     
}
 
/*****演奏子程序2*****/
void play2(void)
{
       unsigned char m=0;
       unsigned char s;     
       unsigned char a=1;
       while(1)
       {
              EA=0;
              LED=0;
              a=yanshi_tone[m];
	      shumaguan=a;
              s=yanshi_beat[m];
              tone1=yinfu[2*a-2];
              tone2=yinfu[2*a-1];
              EA=1;
              while(s--)
              {
                     delay();
              }
              LED=1;
              m++;
              if(m>=32) return;   
       }     
}
 
/*****按键检测*****/
void check_key(void)
{
       P2=0xff;                                    
       P3=0xff;                                           //设置为输入状态
       switch(P2)                          //检测按键，输出数码管、载入定时器初值、允许中断
       {
              case 0xfe:shumaguan=0x1;tone1=0xfb;tone2=0xe9;EA=1;break;
              case 0xfd:shumaguan=0x2;tone1=0xfc;tone2=0x5c;EA=1;break;
              case 0xfb:shumaguan=0x3;tone1=0xfc;tone2=0xc1;EA=1;break;
              case 0xf7:shumaguan=0x4;tone1=0xfc;tone2=0xef;EA=1;break;
              case 0xef:shumaguan=0x5;tone1=0xfd;tone2=0x45;EA=1;break;
              case 0xdf:shumaguan=0x6;tone1=0xfd;tone2=0x92;EA=1;break;
              case 0xbf:shumaguan=0x7;tone1=0xfd;tone2=0xd0;EA=1;break;
              case 0x7f:shumaguan=0x1;tone1=0xfd;tone2=0xee;EA=1;break;
              default: EA=0;SPK=0;shumaguan=0x00;//没有键按下则关闭中断和数码管
       }
       switch(P3)
       {
              case 0xfb:play1();break;
              case 0xf7:play2();break;
       } 
}
 
/*****主程序*****/
void main(void)
{
       initTimer();
       shumaguan=0x00;
       TR0=1;
       ET0=1;
       SPK=0;
       while(1)
       {
              check_key();
       }
}