Timer to count up in JavaScript

Here is my implementation, nothing original or extraordinary. Putting it here for future reference.

        
        var totalSeconds = 0;
        var timer;

        function startTimer() {
            timer = setInterval(function () {
                totalSeconds++;
                var t = document.getElementById("time2"); //or other place where to display data
                t.innerHTML = displayTimer(totalSeconds);
            }, 1000); 
        }

        function stopTimer() {
            clearInterval(timer);
        }

        function displayTimer(numberOfSeconds) {
            var result = "";

            var hours = Math.floor(numberOfSeconds / 3600);
            if (hours > 0) { result += hours + " h "; }

            var minutes = Math.floor((numberOfSeconds - (hours * 3600)) / 60);
            if (minutes > 0) { result += minutes + " m "; }

            result += (numberOfSeconds % 60 + " s");

            return result;
        }