
========================
=  Mapper 231          =
========================

Example Game:
--------------------------
20-in-1



Registers:
---------------------------

 $8000-FFFF:     A~[.... .... M.LP PPP.]
    M = Mirroring (0=Vert, 1=Horz)
    L = Low bit of PRG
    P = High bits of PRG



PRG Setup:
---------------------------

Note that 'L' and 'P' bits make up the PRG reg, and the 'L' is the low bit.


      $8000   $A000   $C000   $E000  
    +---------------+---------------+
    | $8000 AND $1E |     $8000     |
    +---------------+---------------+

