试图理解DateTime :: diff（）函数

Question

the result of the difference between two dates does it well if they are whole hours but without minutes it does not show me the correct data.THE CODE:

$r=strtr($marcacion->marcacion, '/', '-');
$date = date('Y-m-d H:i:s' , strtotime($r));
$dates = new DateTime($date);
$dteDiff  = $temporal->diff($dates);

the variable $temporal is the same case, just is the previous value. AND THE RESULT:

1. ID: 310 value temporal: 21-02-2017 07:30:00 AM ---
   value dates: 21-02-2017 13:03:00 PM total time : 05:33 (should be 06:33)

2. ID: 310 value temporal: 23-02-2017 07:34:00 AM ---
   value dates: 23-02-2017 13:06:00 PM total time : 05:32

3. ID: 316 value temporal: 14-02-2017 13:15:00 PM ---
   value dates: 14-02-2017 17:15:00 PM total time : 04:00