
========================
=  Mapper 075          =
========================


aka:
--------------------------
VRC1


Example Games:
--------------------------
Tetsuwan Atom
Ganbare Goemon! - Karakuri Douchuu



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

Range,Mask:   $8000-FFFF, $F000

  $8000:  [.... PPPP]   PRG Reg 0 (8k @ $8000)
  $A000:  [.... PPPP]   PRG Reg 1 (8k @ $A000)
  $C000:  [.... PPPP]   PRG Reg 2 (8k @ $C000)

  $9000:  [.... .BAM]   Mirroring, CHR reg high bits
     M = Mirroring (0=Vert, 1=Horz)
     A = High bit of CHR Reg 0
     B = High bit of CHR Reg 1

  $E000:  [.... CCCC]   Low 4 bits of CHR Reg 0 (4k @ $0000)
  $F000:  [.... CCCC]   Low 4 bits of CHR Reg 1 (4k @ $1000)


PRG Setup:
---------------------------
      $8000   $A000   $C000   $E000  
    +-------+-------+-------+-------+
    | $8000 | $A000 | $C000 | { -1} |
    +-------+-------+-------+-------+


CHR Setup:
---------------------------

  CHR regs are 5 bits wide.  The low 4 bits of each reg are set by $E000 and $F000, and the high bit is taken
from the appropriate bits of $9000.

      $0000   $0400   $0800   $0C00   $1000   $1400   $1800   $1C00 
    +-------------------------------+-------------------------------+
    |       $9000.1 + $E000         |       $9000.2 + $F000         |
    +-------------------------------+-------------------------------+

