INES Mapper 201: Difference between revisions

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(look through goodnes for m201 games for number of bits in register)
(fix minor error in lead, but really, with the typical bus conflict avoidance sequence, it doesn't really matter whether it uses data or address)
 
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[[Category:iNES Mappers|201]][[Category:Multicart mappers|201]]
[[Category:iNES Mappers|201]][[Category:Multicart mappers|201]]
'''iNES Mapper 201''' has been assigned to a multicart mapper designed to contain multiple NROM-256 games.
It acts like [[BNROM]] and [[CNROM]] overlaid, where one bank number controls both 32 KiB PRG banks and 8 KiB CHR banks, except it uses the address bus instead of the data bus.
   Here are Disch's original notes:   
   Here are Disch's original notes:   
   ========================
   ========================
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       +-------------------------------+
       +-------------------------------+


There are almost assuredly only 2 bits in the above register (all known games are 128KiB PRG / 32KiB CHR)
All known games on this mapper use only the two least significant bits (128KiB PRG / 32KiB CHR).

Latest revision as of 20:48, 19 May 2013

iNES Mapper 201 has been assigned to a multicart mapper designed to contain multiple NROM-256 games. It acts like BNROM and CNROM overlaid, where one bank number controls both 32 KiB PRG banks and 8 KiB CHR banks, except it uses the address bus instead of the data bus.

 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             |
     +-------------------------------+

All known games on this mapper use only the two least significant bits (128KiB PRG / 32KiB CHR).