#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <HX711.h>

#define BUTTON1 18
#define BUTTON2 19
#define BUTTON3 13
#define BUTTON4 14

const int LOADCELL_DOUT_PIN = 16;
const int LOADCELL_SCK_PIN = 17;

LiquidCrystal_I2C LCDDisplay(0x27,16,2);  
HX711 MyScale;
unsigned int WeightValue;

unsigned long TimeCount;

byte Mode=0;




void DisplayMode0()
{
  LCDDisplay.clear(); 
  LCDDisplay.print("1.MSSV  2:TEN");
  LCDDisplay.setCursor(0,1);
  LCDDisplay.print("3.CAN NANG");
}
void DisplayMode1()
{
  LCDDisplay.clear(); 
  LCDDisplay.print("12345");
  LCDDisplay.setCursor(0,1);
  LCDDisplay.print("67890");
}

void DisplayMode2()
{
  LCDDisplay.clear(); 
  LCDDisplay.print("T.HUY - VAN XUAN");
  LCDDisplay.setCursor(0,1);
  LCDDisplay.print("VAN QUANG");
  
}
void DisplayWeight()
{
  WeightValue=MyScale.get_units(1);
  LCDDisplay.setCursor(5,1);
  LCDDisplay.print(WeightValue/1000);
  LCDDisplay.print(".");
  LCDDisplay.print((WeightValue%1000)/100);
  LCDDisplay.print("Kg");
}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  pinMode(BUTTON1,INPUT_PULLUP);
  pinMode(BUTTON2,INPUT_PULLUP);
  pinMode(BUTTON3,INPUT_PULLUP);
  pinMode(BUTTON4,INPUT_PULLUP);

  LCDDisplay.init();
  LCDDisplay.backlight();
  DisplayMode0();
  MyScale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);
  MyScale.set_scale(0.420); //5kg
  MyScale.tare();
  TimeCount=millis();
}

void loop() {
  // put your main code here, to run repeatedly:
  if(millis()-TimeCount>500)
  {
     TimeCount=millis();
     if(Mode==3) DisplayWeight();
  }
  if(digitalRead(BUTTON1)==LOW)
  {
    delay(100);
    while(digitalRead(BUTTON1)==LOW);
    DisplayMode1();
    Mode=1;
  }
  if(digitalRead(BUTTON2)==LOW)
  {
    delay(100);
    while(digitalRead(BUTTON2)==LOW);
    DisplayMode2();
    Mode=2;
  }
  if(digitalRead(BUTTON3)==LOW)
  {
    delay(100);
    while(digitalRead(BUTTON3)==LOW);
    LCDDisplay.clear(); 
    LCDDisplay.print("CAN NANG:");
    Mode=3;
  }
  if(digitalRead(BUTTON4)==LOW)
  {
    delay(100);
    while(digitalRead(BUTTON4)==LOW);
    DisplayMode0();
    Mode=0;
  }

}