#include <LiquidCrystal.h>

LiquidCrystal lcd(9,10, 5,4,3,2);
const int start = 11;
const int stop = 12;
uint8_t time = 0;
bool active = false;

void setup() {
  lcd.begin(16, 2);
  pinMode(start, INPUT_PULLUP);
  pinMode(stop, INPUT_PULLUP);
}



void loop() {
  lcd.clear();
  lcd.print(time);
  if (digitalRead(start) == LOW) {
    while(digitalRead(start))
      if (active == false) {
        active = true;
  }
  }
  if (digitalRead(stop) == LOW) {
      active = false;
  }
  if (active == true) {
    time = time+0.01;
  }
  delay(10);

}