Air_Armonica.ino

/*

  note  frequency
  c     262 Hz
  d     294 Hz
  e     330 Hz
  f     349 Hz
  g     392 Hz
  a     440 Hz
  b     494 Hz
  C     523 Hz

For more information, see http://arduino.cc/en/Tutorial/Tone
*/
#define TRIGGER 5
#define ECHO    4
#define BUZZER_PIN 0

void setup() 
{
  Serial.begin (115200);
  pinMode(TRIGGER, OUTPUT);
  pinMode(ECHO, INPUT);
  pinMode(BUILTIN_LED, OUTPUT);
  pinMode(BUZZER_PIN,OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);
}


void loop() 
{
  
  long duration, distance;
  //int frequency;
  digitalWrite(TRIGGER, LOW);  
  delayMicroseconds(2); 
  
  digitalWrite(TRIGGER, HIGH);
  delayMicroseconds(10); 
  
  digitalWrite(TRIGGER, LOW);
  duration = pulseIn(ECHO, HIGH);
  distance = (duration/2) / 29.1;
  //frequency=map(distance,0,60,200,500);
  if(distance>4 && distance<8){
   tone(BUZZER_PIN,frequency('d'),100);
  }
  else if (distance>8 && distance<20){
   tone(BUZZER_PIN,frequency('g'),100);
  }
  else{
   tone(BUZZER_PIN,frequency('f'),100);
  }
  digitalWrite(BUZZER_PIN,HIGH);
  Serial.print(distance);
  Serial.println("Centimeter:");
  delay(500);
}


int frequency(char note) 
{
  // This function takes a note character (a-g), and returns the
  // corresponding frequency in Hz for the tone() function.

  int i;
  const int numNotes = 8;  // number of notes we're storing

  // The following arrays hold the note characters and their
  // corresponding frequencies. The last "C" note is uppercase
  // to separate it from the first lowercase "c". If you want to
  // add more notes, you'll need to use unique characters.

  // For the "char" (character) type, we put single characters
  // in single quotes.

  char names[] = { 'c', 'd', 'e', 'f', 'g', 'a', 'b', 'C' };
  int frequencies[] = {262, 294, 330, 349, 392, 440, 494, 523};

  // Now we'll search through the letters in the array, and if
  // we find it, we'll return the frequency for that note.

  for (i = 0; i < numNotes; i++)  // Step through the notes
  {
    if (names[i] == note)         // Is this the one?
    {
      return(frequencies[i]);     // Yes! Return the frequency
    }
  }
  return(0);  // We looked through everything and didn't find it,
              // but we still need to return a value, so return 0.
}