//Create and Define Global Variables

int dipPins[] = {2, 3, 4, 5}; //DIP Switch Pins

int transAddress, dur;

//pin which triggers ultrasonic sound

const int pingPin = 13; 

//pin which delivers time to receive echo using pulseIn()

int inPin = 12;

void setup()

{

  Serial.begin(9600);

  int i;

  for(i = 0; i<=3; i++){

  pinMode(dipPins[i], INPUT);      // sets the digital pin 2-5 as input

  digitalWrite(dipPins[i], HIGH); //Set pullup resistor on

  }

  transAddress = address();

  delay(100);

}

void loop()

{

 transAddress = address();

 Serial.println(transAddress);

 if (transAddress == 1){

   dur = 2;

 }

 else if (transAddress == 3) {

   dur = 10;

 }

 else {

   dur = 20;

 }

  long duration, cm;

  //initializing the pin states

  pinMode(pingPin, OUTPUT);

  //sending the signal, starting with LOW for a clean signal

  digitalWrite(pingPin, LOW);

  delayMicroseconds(2);

  digitalWrite(pingPin, HIGH);

  delayMicroseconds(5);

  digitalWrite(pingPin, LOW);

  //setting up the input pin, and receiving the duration in 

  //microseconds for the sound to bounce off the object infront

  pinMode(inPin, INPUT);

  duration = pulseIn(inPin, HIGH);

  // convert the time into a distance

  cm = microsecondsToCentimeters(duration);

  float inches = cm*(.3937);

  int sound = map(inches,0,48,500,2500);

  tone(9,sound,dur);

}

long microsecondsToCentimeters(long microseconds)

{

  // The speed of sound is 340 m/s or 29 microseconds per centimeter.

  // The ping travels out and back, so to find the distance of the

  // object we take half of the distance travelled.

  return microseconds / 29 / 2;

}

//Create Address from DIP Switch (4 positions used)

byte address(){

  int i,j=0;

  //Get the switches state

  for(i=0; i<=3; i++){

  j = (j << 1) | digitalRead(dipPins[i]);   // read the input pin

  }

  return j; //return address

}