- print_r: documentation ( source)
- date: documentation ( source)
- strtotime: documentation ( source)
- range: documentation ( source)
<?php
$date1 = '2014-07-19 13:00';
$date2 = '2014-07-20 13:00';
$date_range = range(strtotime($date1), strtotime($date2), 3600);
foreach ($date_range as $k=>$a)
$date_range[$k] = date('Y-m-d H:i:s', $a);
print_r($date_range);