const unsigned int notes_intro[] = {
  NOTE_E4,
  NOTE_E4,
  NOTE_E4,
  NOTE_C4,
  NOTE_E4,
  NOTE_G4,
  0,
  NOTE_G3,
  0,
};

const unsigned long interval_intro[] = {
  50,
  50,
  100,
  50,
  100,
  200,
  200,
  400,
  800
};