Port 3CF, 06  -  Miscellaneous Register

        1111 xxxx  Reserved
        xxxx 11xx  Memory Map 1/0
                     These bits control the mapping of the regenerative
                     buffer into the system address space. The bit functions
                     are defined in the following figure.
                     Bits
                     3 2    Addressing Assignment
                     0 0    A0000 for 128Kb
                     0 1    A0000 for 64Kb
                     1 0    B0000 for 32Kb
                     1 1    B8000 for 32Kb
        xxxx xx1x  Odd/Even
                     When set to 1, this  bit directs the system address
                     bit, A0, to be replaced by a higher-order bit. The
                     odd map is then selected when A0 is 1, and the even
                     map when A0 is 0.
        xxxx xxx1  Graphics Mode
                     This bit controls alphanumeric mode addressing. When
                     set to 1, this bit selects graphics modes, which also
                     disables the chatacter generator latches.