#include <IRremote.h>
#include <IRremoteInt.h>

//enable IR signal sending ability (only works on digital pin 3!!!)
IRsend irsend;

//these pins can be changed if you like

//pin from center of potentiometer
int potpin = 3;

int val = 0;

int old_val = 0;

int level = 0;

int old_level = 0;

//pin from volume down pushbutton
int downVolpin = 4;

int downVolVal = 0;

//led to indicate changes in volume (for debugging) you can change pin
int indicatorLED = 2;

//volume up 490
//volume down c90

void setup()
{
  Serial.begin(9600);

  pinMode(downVolpin, INPUT);
  
  pinMode(indicatorLED, OUTPUT);
  
}

void loop() {
  
  downVolVal = digitalRead(downVolpin); //state of volume down button
  
  val = analogRead(potpin); // analog value of pot, between 0-1023
  
  level = map(val, 0, 1023, 0, 100); //changes values from 0-1023 to 0-100 
  
  delay(10);
  
  if (downVolVal == HIGH) { // if down volume button is pressed
    for (int i = 0; i < 3; i++) {
      irsend.sendSony(0xc90, 12); // Sony TV down volume (change for your device)
      delay(100);
    }
  }
  else if (level > old_level) { //if knob is turned up
    
    digitalWrite(indicatorLED, HIGH);
    
    for (int i = 0; i < 3; i++) {
      irsend.sendSony(0x490, 12); // Sony TV up volume (change for your device)
      delay(100);
    }
  }
  
  else if (level < old_level) { //if knob is turned down 
    
    digitalWrite(indicatorLED, HIGH);
    
    for (int i = 0; i < 3; i++) {
      irsend.sendSony(0xc90, 12); // Sony TV down volume (change for your device)
      delay(100);
    }
  } else { //if neither action is done
    digitalWrite(indicatorLED, LOW);
  }
  
  old_val = val; //the value is now old
  
  old_level = level; //the mapped value is now old
  
}