INES Mapper 201

 Here are Disch's original notes:  
 ========================
 =  Mapper 201          =
 ========================
 
 Example Games:
 --------------------------
 8-in-1
 21-in-1 (2006-CA) (Unl)
 
 
 Registers:
 ---------------------------
 
 
   $8000-FFFF:  A~[.... ....  RRRR RRRR]
     R = PRG/CHR Reg
 
 
 CHR Setup:
 ---------------------------
 
       $0000   $0400   $0800   $0C00   $1000   $1400   $1800   $1C00 
     +---------------------------------------------------------------+
     |                             $8000                             |
     +---------------------------------------------------------------+
 
 
 PRG Setup:
 ---------------------------
 
      $8000   $A000   $C000   $E000  
     +-------------------------------+
     |             $8000             |
     +-------------------------------+

There are almost assuredly only 2 bits in the above register (all known games are 128KiB PRG / 32KiB CHR)