#include <LiquidCrystal.h>

// Décl des pins
   const int sensorPin = A0;
   const int switchPin = 13 ;
   int previousTmpSensorVal = 0 ;
   float voltage = 0.0;
   float temperatureC = 0.0;
   int switchState = 0 ;

// Constantes du LCD
   const int rs = 12, en = 11, d4 = 5, d5 = 4, d6 = 3, d7 = 2;
   LiquidCrystal lcd(rs, en, d4, d5, d6, d7);

void setup() {
  pinMode(13, INPUT);
  lcd.begin(16,2);
  lcd.print("Affichage");
  lcd.setCursor(0,1);
  lcd.print("Temperature");
  delay(1000);
 // Reinitialisation LCD
    lcd.clear();
}
 
void loop()             
{
 // Lecture de la valeur du capteur
    int tmpSensorVal = analogRead(sensorPin); 
 // Lecture de l'interrupteur
    switchState = digitalRead(switchPin);
    lcd.setCursor(15,1);
    lcd.print(switchState);

  // Valeurx Fixes du LCD
        lcd.setCursor(8,0);
        lcd.print("V:");   
        lcd.setCursor(0,1);
        lcd.print("Temp.:");   
        lcd.setCursor(12,1);
        lcd.print("C");

  // Si changement capteur, on (re)calcule la temperature
       if (tmpSensorVal != previousTmpSensorVal )  {
       // Calcul du volatge et conversion en degré Celsius
          voltage = tmpSensorVal * 5.0;
          voltage /= 1024.0;
          temperatureC = (voltage - 0.5) * 100 ;
          previousTmpSensorVal = tmpSensorVal ;
          }
  // Affichage sur demande (appui switch)   
       if (switchState == 1) {
           // Affichage LCD
              lcd.display();
              lcd.setCursor(0,0);
              lcd.print(tmpSensorVal);
              lcd.setCursor(10,0);
              lcd.print(voltage);
              lcd.setCursor(7,1);
              lcd.print(temperatureC);   
              delay(10000);
           } else { // On éteint le LCD
              lcd.noDisplay();
           }
delay(500); 
}