Change time of this script?

This script currently counts down how many minutes and seconds are back for the current our.


Is it possible to do so it count down to every 5 minute?
I hope it is possible.


Code:

function countDown() {var now = new Date();var sec = 60 - now.getSeconds();   // set the secondsvar min = 59 - now.getMinutes();  // set the minutes
  if (sec == -01) {    sec = 59;    min = min - 1;  } else {   min = min;  }if (sec<=9) { sec = "0" + sec; }  time = "Time til next cycle " + (min<=9 ? "0" + min : min) + ":" + sec;if (document.getElementById) { count.innerHTML = time; }  SD=window.setTimeout("countDown();", 1000);if (min == '00' && sec == '00') {     min = "59";     sec = "60";     }}

function countUp(){var thetime=new Date();var hours=thetime.getHours();var mins=thetime.getMinutes();var secn=thetime.getSeconds();var day=thetime.getDay();var AorP=" ";
if (secn<10)secn="0"+nsecn;
if (mins<10)mins="0"+mins;
if (day==0)  day="Sunday";if (day==1)  day="Monday";if (day==2)  day="Tuesday";if (day==3)  day="Wednesday";if (day==4)  day="Thursday";if (day==5)  day="Friday";if (day==6)  day="Saturday";
if (document.getElementById) { theTime.innerHTML = day+", "+hours+":"+mins+":"+secn; }  SD=window.setTimeout("countUp();", 1000);} 


function addLoadEvent(func) {  var oldonload = window.onload;  if (typeof window.onload != 'function') {    window.onload = func;  } else {    window.onload = function() {      if (oldonload) {        oldonload();      }      func();    }  }}
addLoadEvent(function() {  countDown();  countUp();});

PHP:

 

not sure but its possible through setTimeout function.

 

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