<?php
	$minutes = date('i'); // We'll go by the minutes of the hour so that we don't have to compare to all 24 possible outcomes
	
	if($minutes == '00'){ // if the minutes are 0 which should be the top of the hour
		echo "true"; // then pass a true to the refresh function
	} else{
		echo "false"; // if not, pass a false
	}
?>

Php check for the top of the hour

Php check for the top of the hour

php

PHP