#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27,16,2);
LiquidCrystal_I2C lcd1(0x28,20,4);

#define start 2
#define reset 3


int sensorA=9; //Initalize Pin9 for Sensor A
int sensorB=10; //Initalize Pin10 for Sensor B



unsigned long began, quit, stopwatch;
unsigned long t1=0,t2=0; //Define Time1 and Time2 Variable

float speed; // Define Speed Vairable
float distance=1; //Define Distance value
int i=0;

//int fPause=0;
long lastButton=0;
//long delayBouncing=50;
//long dataPaus=0;

void setup() {
  // put your setup code here, to run once:
  pinMode(start, INPUT_PULLUP); //Start Button 
  pinMode(reset, INPUT_PULLUP); //Reset Button

  pinMode(sensorA, INPUT_PULLUP); //SensorA Input
  pinMode(sensorB, INPUT_PULLUP); //sesnorB Input

  pinMode(12, OUTPUT);
  
  //pinMode(BLK,OUTPUT);
  //digitalWrite(BLK,HIGH);

  lcd.init();
  //lcd1.init();
  lcd.clear();
  //lcd1.clear();
  lcd.backlight();
  //lcd1.backlight();

  //lcd1.setCursor(0,1);
  lcd.print("Waiting...");
  delay(1000);
  lcd.clear();
  lcd.print(" KRRI SpeedMeter");
  lcd.setCursor(0,1);
  lcd.print(" Start / Reset");
  //lcd1.print("Next Hello");
  
}

void loop() {
  // put your main code here, to run repeatedly:

  if(digitalRead(start)==0){
    
    setup();
    //digitalWrite(BLK,);
    
    /*
    lcd.clear();
    lcd.print("SPEED Checking!");
    delay(500);
    ///lcd.blink();
    lcd.clear();
    lcd.setCursor(0,1);
    lcd.print(digitalRead(start));
    delay(1000);
    //i++;
    //lcd.print(i);
    */
    lcd.clear();
    lcd.print("SPEED CHECKING!");
    blink_led();
    while(digitalRead(sensorA)); //Read Sensor A
    while(digitalRead(sensorA)==0);
    t1=millis(); //Record Time1
    while(digitalRead(sensorB)); //Read Sensor B
    t2=millis();  //Record Time2
    speed=t2-t1;
    speed=speed/1000;  //convert millisecond to second
    speed=(distance/speed);  //v=d/t
    speed=speed*3600;  //multiplay by seconds per hr
    speed=speed/1000; //division by meters per km
    
    for(int i=3;i>0;i--){
      lcd.clear();
      lcd.setCursor(0,0);
      lcd.print("Train Speed= ");
      lcd.setCursor(3,1);
      lcd.print(speed);
      lcd.print("  km/h  ");
    }
    //lcd.noBacklight();
    /*
    lcd.clear();
    lcd.setCursor(0,1);
    lcd.print(digitalRead(sensorA));
    lcd.print(" | ");
    lcd.print(digitalRead(sensorB));
    */


  }else if(digitalRead(reset)==0){
    lcd.clear();
    
    setup();
  }
}
void blink_led(){
  for(digitalRead(start)==0; ;digitalRead(sensorA)==0 ){
    digitalWrite(12, HIGH);
    delay(500);
    digitalWrite(12, LOW);
    delay(500);   
  }

  
 
}