void setup() {
  Serial.begin(115200);
  pinMode(A2, INPUT);
}

void loop() {
  static int adw_alt = -42, adw;
  static float U, Temp;  

  adw = analogRead(A2); 
  if( abs( adw_alt - adw ) > 3 ) 
  {
    U = 5.0 * adw / 1.023 ; 
    Temp = (U - 500) / 10.0 ; 
    adw_alt = adw; 

    Serial.print("ADW = " + String( adw ) + ": ");
    Serial.print( U, 1 ); 
    Serial.print(" mV = " );
    Serial.print( Temp, 1 );
    Serial.println( "°C ") ; 
    delay(100);
  }

}