无源蜂鸣器

代码示例：

//小星星（带休止符）
#define bp 2  //IO02
#define chanel 0
typedef struct data {
  note_t note; //音符
  uint8_t level; //音阶 4 为我们平常时所听到的那个8度
  uint16_t interval; //持续时间
  int x; //音符播放后的空时间
} note;

note tones[]={
  {NOTE_C,4,500,0},
  {NOTE_C,4,500,0},
  {NOTE_G,4,500,0},
  {NOTE_G,4,500,0},
  {NOTE_A,4,500,0},
  {NOTE_A,4,500,0},
  {NOTE_G,4,725,250},
  {NOTE_F,4,500,0},
  {NOTE_F,4,500,0},
  {NOTE_E,4,500,0},
  {NOTE_E,4,500,0},
  {NOTE_D,4,500,0},
  {NOTE_D,4,500,0},
  {NOTE_C,4,725,250},
  {NOTE_G,4,500,0},
  {NOTE_G,4,500,0},
  {NOTE_F,4,500,0},
  {NOTE_F,4,500,0},
  {NOTE_E,4,500,0},
  {NOTE_E,4,500,0},
  {NOTE_D,4,725,250},
  {NOTE_G,4,500,0},
  {NOTE_G,4,500,0},
  {NOTE_F,4,500,0},
  {NOTE_F,4,500,0},
  {NOTE_E,4,500,0},
  {NOTE_E,4,500,0},
  {NOTE_D,4,725,250},
  {NOTE_C,4,500,0},
  {NOTE_C,4,500,0},
  {NOTE_G,4,500,0},
  {NOTE_G,4,500,0},
  {NOTE_A,4,500,0},
  {NOTE_A,4,500,0},
  {NOTE_G,4,725,250},
  {NOTE_F,4,500,0},
  {NOTE_F,4,500,0},
  {NOTE_E,4,500,0},
  {NOTE_E,4,500,0},
  {NOTE_D,4,500,0},
  {NOTE_D,4,500,0},
  {NOTE_C,4,725,250},
}; //曲子包含所有的音符
//NOTE_C do
//NOTE_Cs 升do
//NOTE_D re
//NOTE_Eb 降mi 
//NOTE_E mi
//NOTE_F fa
//NOTE_Fs 升fa
//NOTE_G sol
//NOTE_Gs 升sol
//NOTE_A la
//NOTE_Bb 降ti
//NOTE_B ti

byte tonesSize=sizeof(tones)/sizeof(note);

void xiuzhi(uint8_t channel,unsigned long long deley)
{
  ledcWriteTone(channel,0);
  delay(deley);
}

void setup()
{
  // put your setup code here, to run once:
  ledcSetup(chanel,20000,10);
  ledcAttachPin(bp,0);
}
void loop()
{
  // put your main code here, to run repeatedly:
  // ledcWriteTone(0,200);
  // delay(200);
  // ledcWriteTone(0,500);
  // delay(200);
  // ledcWriteNote(0,NOTE_C,4);
  // delay(500);
  for(int i=0;i<tonesSize;i++)
  {
    ledcWriteNote(chanel,tones[i].note,tones[i].level);
    delay(tones[i].interval);
    xiuzhi(chanel,tones[i].x);
  }
}