#include <LiquidCrystal_I2C.h>     // if you don´t have I2C version of the display, use LiquidCrystal.h library instead

LiquidCrystal_I2C lcd(0x27,20,4);  // set the LCD address to 0x27 for a 16 chars and 2 line display
int tempo; //to store the millis() function
int rd_tm = 500; //[ms] to set time of reading
int read = 0;
float volt = 0;
float pressure = 0;

//support variable 
bool debug = 0; //For print more info in the serial port
bool display = 1; //To print on diplay

void setup() {
  //presentazione
  if (display)
  {
    lcd.init();                      // initialize the lcd 
    lcd.backlight();
    lcd.setCursor(4,0);
    lcd.print("-----------");
    lcd.setCursor(4,1);
    lcd.print("|");
    lcd.setCursor(5,1);
    lcd.print("TRASDUINO");
    lcd.setCursor(14,1);
    lcd.print("|");
    lcd.setCursor(4,2);
    lcd.print("-----------");
    delay(2000);

    //impostazione
    lcd.clear();
    lcd.setCursor(1,1);
    lcd.print("configurazione....");
  }
  

  Serial.begin(115200);
  Serial.print("--Setup--");
  pinMode(A0,INPUT);

  //Set up
  if (display)
  {
    lcd.clear();
    lcd.setCursor(0,1);
    lcd.print("Sen_1(A0): ");
    //Print of the interface
    lcd.setCursor(16,3);
    lcd.print("[V]");
    //
    lcd.setCursor(15,1);
    lcd.print("[Bar]");
  }
  
  Serial.print("\n\n--interface printing--");
  Serial.print("----------TRASDUINO-----------");

}

//this function convert the value readed by the analog port to the corrispondent voltage value 
float readToVolt(int read, float scale)
{
  if(debug)
  {
    Serial.print("|   |scale -> ");
    Serial.print(scale);
  }
  float volt = read*scale;
  Serial.print("|   |Volt -> ");
  Serial.print(volt);
  return volt;
}

//this function convert the Voltage value in Bar (linear correlation)
float VoltToBar(int volt)
{
  float Bar = volt*35 -32.97; //empirical relation for the sensor
  Serial.print("|   |Bar -> ");
  Serial.print(Bar);
  return Bar;
}

void loop() 
{
  //start
  tempo = millis();
  read = analogRead(A0);
  if (debug)
  {
    Serial.print("\n\n time ->");
    Serial.print(tempo);
    
    Serial.print("|   |read ->");
    Serial.print(read); 
  }
  else
  {
    Serial.print("\n\n");
  }
 

  //update the display
    
    //voltage printing
    volt = readToVolt(read,0.005);
    if(display)
    {
      lcd.setCursor(12,3);
      lcd.print(volt);
    }
    
    
    //pressire printing
    pressure = VoltToBar(volt);
    if (display)
    {
      lcd.setCursor(10,1);
      lcd.print(pressure);
    }

    delay(rd_tm);
}