Theremino

//In this project we create a theremin with two ultrasonic sensors, one for volume and another for tone. We use the digital potentiometer X9C103P.
/*                                                                                                                                                                                                                                               
 * Potentiometer conecctions:
 * 1 - INC - Arduino pin 2
 * 2 - U/D - Arduino pin 3
 * 3 - VH  - 5V
 * 4 - VSS - GND
 * 5 - VW  - Output
 * 6 - VL  - GND
 * 7 - CS  - Arduino pin 4
 * 8 - VCC - 5V
 *
 */
//Note: we include two libraries: NewPing and TonePlayer because if we use the library NewPing with a tone function, the sketch doesnot compile. 
#include <NewPing.h> 
#include <TonePlayer.h>
#define MIN_DISTANCIA 35 
TonePlayer tone1(TCCR1A, TCCR1B, OCR1AH, OCR1AL, TCNT1H, TCNT1L); 

NewPing sonar(10, 11, 35); //The first and the second number are the pins of the sensor of volume, the third is the maximum distance 

// name pins for sensors and the potentiometer
int echo = 12;                            
int trigger = 13;
int INC = 2;
int UD = 3;
int distancia;
int actual, anterior;
// necessary variables
unsigned long tiempoRespuesta;
float distancia2;
float tono1;

void setup() {
// set all the pins 
Serial.begin(9600); //use of monitor serie for check the distance
pinMode(trigger, OUTPUT); //Tone sensor                    
pinMode(echo, INPUT); //Tone sensor    
pinMode(2, OUTPUT); //Potentiometer
pinMode(3, OUTPUT); //Potentiometer
//pinMode (speaker, OUTPUT);

for(int j=0; j<90; j++){ //As we do not know in what value the potentiometer is, we place the value at the minimum
     decremento(); 
  }  
  
}

void loop() {
  
  digitalWrite(trigger, HIGH);           
  delayMicroseconds(10);   // Pulse of ten microseconds                      
  digitalWrite(trigger, LOW);                   
  tiempoRespuesta = pulseIn(echo, HIGH);  // Echo of the pulse
  distancia2 = tiempoRespuesta/58;  //Calculation of the distance in centimeters

  if (distancia2 < MIN_DISTANCIA) { 
  //Conversion of distance into a value for a sound 
  tono1 = 50.0*pow(2,(distancia2/12.0));  //pow alculates the value of a number raised to a power
  pinMode(9, OUTPUT);
  tone1.tone(tono1);  //Generates the tone with the previous value (220 Hz) 
  delay(10); 
  }

distancia = sonar.ping_cm(); //Calculation of the distance in centimeters (with the library NewPing)
Serial.print(distancia); //Check the distance
//Change the value "distancia", to values that are useful for the rise and fall of the potentiometer
actual = map(distancia, 0, 35, 0, 200);

//Compares the mapped values to raise or lower the potentiometer
if(actual > anterior){
  for(int i = 0; i< (actual - anterior); i++){
  decremento();
  }
}

else{
  for(int i = 0; i <= (anterior - actual); i++)
  {
  aumento();
  }
}

anterior = actual; //The value is updated with each loop
delay(1);

  
}

//The U/D input controls the direction of the wiper movement and whether the counter is incremented or decremented
//The INC input is negative-edge triggered. Toggling INC will move the wiper and either increment or decrement the counter in the direction indicated by the logic level on the U/D input.
//The next two functions produce these toggling in the two directions (increment, decrement)

void aumento(){ //aumento == increment
digitalWrite(UD, HIGH);
digitalWrite(INC, LOW);
digitalWrite(INC, HIGH);
delay(10);
digitalWrite(INC, LOW);
}

void decremento(){ //decremento == decrement
digitalWrite(UD, LOW);
digitalWrite(INC, LOW);
digitalWrite(INC, HIGH);
delay(10);
digitalWrite(INC, LOW);
}