Table 237

+=====-========-========-========-========-========-========-========-========+ 
|  Bit|   7    |   6    |   5    |   4    |   3    |   2    |   1    |   0    | 
|Byte |        |        |        |        |        |        |        |        | 
|=====+=======================================================================| 
| 0   |                           Reserved                                    | 
|-----+-----------------------------------------------------------------------| 
| 1   |                           M field                                     | 
|-----+-----------------------------------------------------------------------| 
| 2   |                           S field                                     | 
|-----+-----------------------------------------------------------------------| 
| 3   |                           F field                                     | 
+=============================================================================+