#define analogPin A0



const uint8_t controlPins[] = { 2, 3, 4, 5 };
int threshold = 1;
float valueold[16]; //Integerarray
float readMux(int channel)
{
  for(int i = 0; i < 4; i ++)
  {
    digitalWrite(controlPins[i], channel >> i & 1);
  }
  delay(10);
  return analogRead(analogPin);
}

void setup()
{
  Serial.begin(9600);
  for (int i = 0; i < 4; ++i)
  {
    pinMode(controlPins[i], OUTPUT);
  }
  
}

void loop()
{
for (int i = 0; i < 16; i++) {
  // Read current channel value
  int current_value = readMux(i);

  // Calculate absolute difference from previous value
  int difference = abs(current_value - valueold[i]);

  // Detect changes both upwards and downwards
  if (difference >= threshold) {
    valueold[i] = current_value; // Update reference value
    Serial.print("Channel ");
    Serial.print(i);
    Serial.print(": ");
    Serial.println(current_value);
    //Serial.print("Change: ");
    //Serial.println(difference);

 
  }
 }   
}