2Hours Stopwatch with display


I want to made arduino base 2Hours Stopwatch with display.


  1. When i press start button timer will start for two hours.
  2. And display the remaining times.
  3. After 2 hours finished one alarm will ring.
  4. When i press reset button timer will again set 2 hours. (Normal position)

Please guide me ....

Thanks in advance

Please post your code, show what you tried.

What do you want to have happen if the reset button is pressed before the alarm rings? What if the start button and the reset button are pressed together? What if there are multiple presses of the reset button? What if there are multiple presses of the start button? What if the alarm rings and then the start button is pressed?

Start simple (for example, displaying a number) and build up slowly to your goal.

Start from here

#include <StopWatch.h>
#include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

StopWatch sw_millis;    // MILLIS (default)
StopWatch sw_micros(StopWatch::MICROS);
StopWatch sw_secs(StopWatch::SECONDS);

void setup() {

void loop() {

    lcd.print(" ms=");
    lcd.setCursor(0, 1);