INES Mapper 087: Difference between revisions

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(m101 doesn't exist, so shouldn't be preferred.)
("misinterpreted" is a bit loaded, as it could just as easily be interpreted as the mask ROMs having a swapped pinout. In this sense 101 does exist.)
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   CHR, so the 'H' bit is usually unused.
   CHR, so the 'H' bit is usually unused.


[[iNES Mapper 101]] is the exact same board, but the bits misinterpreted as in order. [[CNROM]] (which postdates mapper 87) is the same but with the bits in order and bus conflicts.
[[iNES Mapper 101]] refers to the exact same board, but the banks are stored in the ROM image in logical order.
[[CNROM]] (which postdates mapper 87) is the same but with the bits in order and bus conflicts.

Revision as of 00:13, 25 April 2014

 Here are Disch's original notes:  
 ========================
 =  Mapper 087          =
 ========================
 
 
 Example Games:
 --------------------------
 Argus (J)
 City Connection (J)
 Ninja Jajamaru Kun
 
 
 Notes:
 ---------------------------
 Regs are at $6000-7FFF, so these games have no SRAM.
 
 
 Registers:
 --------------------------
 
   $6000-7FFF:  [.... ..LH]
     H = High CHR Bit
     L = Low CHR Bit
 
   This reg selects 8k CHR @ $0000.  Note the reversed bit orders.  Most games using this mapper only have 16k
 CHR, so the 'H' bit is usually unused.

iNES Mapper 101 refers to the exact same board, but the banks are stored in the ROM image in logical order. CNROM (which postdates mapper 87) is the same but with the bits in order and bus conflicts.