FMODE

         This register controls the fetch mechanism for different
         types of Chip RAM accesses:


         +-------+----------+-------------------------------------------+
         | BIT#  | FUNCTION | DESCRIPTION                               |
         +-------+----------+-------------------------------------------+
         | 15    | SSCAN2   | Global enable for sprite scan-doubling.   |
         | 14    | BSCAN2   | Enables the use of 2nd P/F modulus on an  |
         |       |          | alternate line basis to support bitplane  |
         |       |          | scan-doubling.                            |
         | 13-05 | Unused   |                                           |
         | 04    | SAGA     | Enable SAGA New features                  |
         | 03    | SPAGEM   | Sprite page mode (double CAS)             |
         | 02    | SPR32    | Sprite 32 bit wide mode                   |
         | 01    | BPAGEM   | Bitplane Page Mode (double CAS)           |
         | 00    | BLP32    | Bitplane 32 bit wide mode                 |
         +-------+----------+-------------------------------------------+