Hide and Show buttons based on field

//Initialize time attributes
var seconds = 0, minutes = 0, hours = 0,t;
function add() {
    seconds++;
    if (seconds >= 60) {
        seconds = 0;
        minutes++;
        if (minutes >= 60) {
            minutes = 0;
            hours++;
        }
    }

	//creating time value in hh:mm:ss formate
    var tmp = (hours ? (hours > 9 ? hours : "0" + hours) : "00") + ":" + (minutes ? (minutes > 9 ? minutes : "0" + minutes) : "00") + ":" + (seconds > 9 ? seconds : "0" + seconds);
	Xrm.Page.getAttribute("new_timer").setValue(tmp);

	//recursively calling timer
    timer();
}

//main timer method
function timer() {
    t = setTimeout(add, 1000);
}

function pause()
{
    clearTimeout(t);
}

function resume()
{
    clearInterval(t);
    timer();
}