Table 237
+=====-========-========-========-========-========-========-========-========+
| Bit| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
|Byte | | | | | | | | |
|=====+=======================================================================|
| 0 | Reserved |
|-----+-----------------------------------------------------------------------|
| 1 | M field |
|-----+-----------------------------------------------------------------------|
| 2 | S field |
|-----+-----------------------------------------------------------------------|
| 3 | F field |
+=============================================================================+