#include <LiquidCrystal_I2C.h>
#include "HX711.h"
LiquidCrystal_I2C lcd(0x27, 20, 4);

#define calibration_factor_pet 420
#define calibration_factor_sup 420
#define calibration_factor_bc 420
#define calibration_factor_tin 420

#define LOADCELL_DOUT_PIN1 A0
#define LOADCELL_SCK_PIN1 A1
#define LOADCELL_DOUT_PIN2 A2
#define LOADCELL_SCK_PIN2 A3
#define LOADCELL_DOUT_PIN3 A4
#define LOADCELL_SCK_PIN3 A5
#define LOADCELL_DOUT_PIN4 A6
#define LOADCELL_SCK_PIN4 A7
#define relay_pet 3
#define relay_sup 4
#define relay_bc 6
#define relay_tin 7

HX711 scale_pet;
HX711 scale_sup;
HX711 scale_bc;
HX711 scale_tin;

float pet;
float sup;
float bc;
float tin;

void setup() {
  Serial.begin(9600);
  Serial.println("HX711 scale demo");
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0,1);
  lcd.print("HX711 scale demo");

  scale_pet.begin(LOADCELL_DOUT_PIN1, LOADCELL_SCK_PIN1);
  scale_sup.begin(LOADCELL_DOUT_PIN2, LOADCELL_SCK_PIN2);
  scale_bc.begin(LOADCELL_DOUT_PIN3, LOADCELL_SCK_PIN3);
  scale_tin.begin(LOADCELL_DOUT_PIN4, LOADCELL_SCK_PIN4);

  scale_pet.set_scale(calibration_factor_pet);
  scale_sup.set_scale(calibration_factor_sup);
  scale_bc.set_scale(calibration_factor_bc);
  scale_tin.set_scale(calibration_factor_tin);
  delay(2000);
  lcd.clear();
}

void loop() {
  pet = scale_pet.get_units();
  sup = scale_sup.get_units();
  bc = scale_bc.get_units();
  tin = scale_tin.get_units();

  Serial.print("Weight: ");
  Serial.print(pet);
  Serial.print(" ");

  Serial.print("Weight: ");
  Serial.print(sup);
  Serial.print(" ");

  Serial.print("Weight: ");
  Serial.print(bc);
  Serial.print(" ");

  Serial.print("Weight: ");
  Serial.println(tin);

  lcd.setCursor(0,0);
  lcd.print("Weight: ");
  lcd.print(pet);

  lcd.setCursor(0,1);
  lcd.print("Weight: ");
  lcd.print(sup);

  lcd.setCursor(0,2);
  lcd.print("Weight: ");
  lcd.print(bc);

  lcd.setCursor(0,3);
  lcd.print("Weight: ");
  lcd.print(tin);
}