//喇叭控制接腳 
const int speaker = 7;
//樂曲速度
int tempo=250;

//低音頻率表 lfreqs[1]=>低音Do
int lfreqs[] = {0,131,147,165,175,196,220,247};
//中音頻率表 freqs[1]=>Do
int freqs[] = {0,262,294,330,349,392,440,494};
//高8度音頻率表 hfreqs[1]=>高音Do
int hfreqs[] = {0,523,587,659,698,784,880,988};
//高16度音頻率表 shfreqs[1]=>高16度音Do
int shfreqs[] = {0,1046,1175,1318,1397,1568,1760,1976};

float song[]={
              //音階,拍子
              5,1,3,1,3,2,
              4,1,2,1,2,2,
              1,1,2,1,3,1,4,1,
              5,1,5,1,5,2,

              5,1,3,1,3,2,
              4,1,2,1,2,2,
              1,1,3,1,5,1,5,1,
              3,3,0,1,

              2,1,2,1,2,1,2,1,
              2,1,3,1,4,2,

              3,1,3,1,3,1,3,1,
              3,1,4,1,5,2,

              5,1,3,1,3,2,
              4,1,2,1,2,2,
              1,1,3,1,5,1,5,1,
              1,4
            };
            
void setup() {  
  pinMode(speaker,OUTPUT);
  
}

void loop() {
  //計算陣列長度
  int num=sizeof(song)/sizeof(float);
  int freq;
  for(int i=0;i<num;i+=2){
    if(song[i]>10){
      //高音 10=>Do 20=>Re
      freq=hfreqs[int(song[i]/10)];
    }else if(song[i]<1 && song[i]>0){
      //低音 0.1=>Do 0.2=>Re
       freq=lfreqs[int(song[i]*10)];
    }else{
      //中音 1=>Do 2=>Re
      freq=freqs[int(song[i])];    
    }
    tone(speaker,freq,song[i+1]*tempo);  
    delay(song[i+1]*tempo);
    delay(tempo/20);    
  }  
  while(1){
    delay(1000);
  }  

}