INES Mapper 224: Difference between revisions

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(Turns out that 224 is actually a multicart mapper used for stand-alone Chinese RPGs.)
 
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{{DEFAULTSORT:224}}[[Category:MMC3-like mappers]][[Category:Mappers with scanline IRQs]]
{{DEFAULTSORT:224}}[[Category:MMC3-like mappers]][[Category:Mappers with scanline IRQs]]
iNES Mapper 224 is used for the 晶科泰 (Jncota) KT-008 PCB. It's an MMC3 clone that supports 1024 KiB of PRG-ROM through an additional outer bank register at $5000.
iNES Mapper 224 is used for the 晶科泰 (Jncota) KT-008 PCB. It includes the same chipset as the "MINDKIDS" multicarts ([[NES 2.0 Mapper 268]], Submapper 1).
 
=Registers=
==MMC3-compatible Registers==
Mask: $E001
$8000, $8001, $A000, $A001, $C000, $C001, $E000, $E001: As normal MMC3.
 
==Outer Bank Register ($5000)==
Mask: unknown, but probably $F003.
7654 3210
---------
.... .P..
      +-- Select outer 512 KiB PRG-ROM bank
 
==Other registers ($5001-$5003)==
Mask: unknown, but probably $F003.
 
Meaning unknown; games just write $00 to them.
=Notes=
* Because the outer bank register is initialized to $00 at power-on, these games boot with the $E000 bank from the ''first'' 512 KiB half.
* Most of these ROM images are incorrectly set to Mapper 4, thus sharing a mapper number with oversize [[TxROM|TNROM]] images having 1024 KiB of PRG-ROM. Oversize TNROM switches 512 KiB banks through bits 6-7 of MMC3 bank registers 6 and 7 and initializes them to $FE and $FF, causing them to boot with the $E000 bank from the ''second'' 512 KiB half.

Latest revision as of 23:27, 27 October 2019

iNES Mapper 224 is used for the 晶科泰 (Jncota) KT-008 PCB. It includes the same chipset as the "MINDKIDS" multicarts (NES 2.0 Mapper 268, Submapper 1).