#include <Wire.h>
#include <LiquidCrystal_I2C.h>

const int pressureInput = A0;
const int pressureZero = 102.4;
const int pressureMax = 921.6;
const int pressureTransducerMaxPSI = 100;
const int baudRate = 9600;
const int sensorReadDelay = 250;
const int redLed = 9;
const int greenLed = 8;
int LED1 = 13;
int LED2 = 12;
float pressureValue = 0;

LiquidCrystal_I2C lcd(0x27, 20, 4);


void setup()
{
  Serial.begin(baudRate);
  lcd.init();
  lcd.init();
  lcd.backlight();
  pinMode(redLed, OUTPUT);
  pinMode(greenLed, OUTPUT);
  digitalWrite(redLed, 0);
  digitalWrite(greenLed, 0);

}


void loop()
{
  pressureValue = analogRead(pressureInput);
  pressureValue = ((pressureValue - pressureZero) * pressureTransducerMaxPSI) / (pressureMax - pressureZero);
  Serial.print(abs(pressureValue), 1);
  Serial.println("PSI");
  lcd.setCursor(0, 0);
  lcd.print("Pressure:");
  lcd.print(abs(pressureValue), 1);
  lcd.print("psi     ");
  //lcd.print("psi");
  delay(sensorReadDelay);

  if (abs(pressureValue) < 1) {
    digitalWrite(redLed, 1);
    digitalWrite(greenLed, 0);
  }
  else {
    digitalWrite(redLed, 0);
    digitalWrite(greenLed, 1);
  }
}