^                                                                  t          
  |   t  t  t  t  t                                               t  t          
  |   t  t  t  t  t                                            t  t  t  t       
  |   t  t  t  t  t                                            t  t  t  t  t    
  |   t  t  t  t  t  t  t  t                                t  t  t  t  t  t    
  |   t  t  t  t  t  t  t  t  t                             t  t  t  t  t  t    
  |   t  t  t  t  t  t rt  t  t                             t  t  t  t  t  t    
  |  rt  t  t  t  t  t rt  t  t                          t  t  t  t  t  t  t    
  |  rt  t  t  t  t  t rt  t  t  t       r            t  t  t  t rt  t  t  t    
  |  rt rt  t  t  t  t rt  t  t rt  t  t rt r  r  rt  t  t  t  t rt rt  t  t    
 -+---------------------------------------------------------------------------> 
  |  15 16 17 18 19 20 21 22 23 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14