INES Mapper 225: Difference between revisions
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m (discredit theoretical 74'170) |
(Added link to Dish and unknown author's doccument. The only reason I don't remove dish notes is because there is nothing else, but this should be re-factored in Wiki format, or deleted later) |
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Nestopia does not implement the 4 × 4 bit RAM, and FCEUX ceased to support it between 2.1.5 and 2.2.1 | Nestopia does not implement the 4 × 4 bit RAM, and FCEUX ceased to support it between 2.1.5 and 2.2.1 | ||
== See also == | |||
* [http://www.romhacking.net/documents/362/ NES Mapper List] by Dish | |||
* [http://nesdev.org/225.txt iNES mapper 225], unknown author | |||
Revision as of 09:58, 21 April 2015
Here are Disch's original notes:
========================
= Mapper 225 =
========================
Example Games:
--------------------------
52 Games
58-in-1
64-in-1
Registers:
---------------------------
$5800-5803: [.... RRRR] RAM (readable/writable)
(16 bits of RAM -- 4 bits in each of the 4 regs)
$5804-5FFF: mirrors $5800-5803
$8000-FFFF: A~[.HMO PPPP PPCC CCCC]
H = High bit (acts as bit 7 for PRG and CHR regs)
M = Mirroring (0=Vert, 1=Horz)
O = PRG Mode
P = PRG Reg
C = CHR Reg
CHR Setup:
---------------------------
$0000 $0400 $0800 $0C00 $1000 $1400 $1800 $1C00
+---------------------------------------------------------------+
CHR Mode 0: | $8000 |
+---------------------------------------------------------------+
PRG Setup:
---------------------------
$8000 $A000 $C000 $E000
+-------------------------------+
PRG Mode 0: | <$8000> |
+-------------------------------+
PRG Mode 1: | $8000 | $8000 |
+---------------+---------------+
Nestopia does not implement the 4 × 4 bit RAM, and FCEUX ceased to support it between 2.1.5 and 2.2.1
See also
- NES Mapper List by Dish
- iNES mapper 225, unknown author
