INES Mapper 210: Difference between revisions

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m (Rephrase to avoid "some claim ... others claim" construction)
(add Naruko's blog's post on mirroring on the 340 from the mapper 019 page, and update the $E000 register mirroring bits to match those docs (which I corroborated by investigating wagyan 2 bugs; I checked dream master and famitsu '92 to ensure still workin)
 
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This mapper represents the NAMCOT-175 board, used for ''Wagyan 2'' and ''Splatterhouse 2''.
{{DEFAULTSORT:210}}{{Infobox_iNES_mapper
It is very similar to [[iNES Mapper 019]], having a [[Namco 106]] with no [[Namco 163 audio|N163 expansion sound]].
|name=Namco 175
|company=Namco
|mapper=210
|nescartdbgames=4
|boards=110F0B
|complexity=ASIC
|prgmax=512K
|prgpage=8Kx3 + 8K fixed
|wrammax=8K
|wrampage=8K
|chrmax=256K
|chrpage=1Kx8
|mirroring=H or V fixed
|busconflicts=No
|irq=No
|audio=No
}}{{Infobox_iNES_mapper
|name=Namco 340
|company=Namco
|mapper=210
|nescartdbgames=8
|boards=CS000x
|complexity=ASIC
|prgmax=512K
|prgpage=8Kx3 + 8K fixed
|wrammax=none
|wrampage=none
|chrmax=256K
|chrpage=1Kx8
|mirroring=H, V, or 1 switchable
|busconflicts=No
|irq=No
|audio=No
}}
iNES Mapper 210 is used to denote Famicom boards bearing either the Namco 175 (Submapper 1) or Namco 340 (Submapper 2) ASIC. Both can be thought of as cost-reduced versions of the [[INES Mapper 019|Namco 163]]:
{| class="wikitable"
! Function !! N163 !! N175 !! N340
|-
|IRQ counter || Yes || No || No
|-
|ROM nametables || Yes || No || No
|-
|Optional WRAM || Yes || Yes || No
|-
|Expansion audio || Yes || No || No
|-
|ASIC-internal RAM || Yes || No || No
|-
|Mirroring || Selectable (extended) || Hard-wired H/V || Selectable H/V/0
|-
|}


The original intent for this mapper is that it has hardwired mirroring (like [[TxROM|TFROM]]); subsequent research questions whether this is actually necessary, and that games seem to only rely on a well-defined default mirroring (which should be set in the iNES header, but is expected always to be vertical, due to the practical necessity of the mirroring being implemented through uniform [[Namco 106]] registers default values)
==Game list==
===Namco 175 (Submapper 1)===
{| class="wikitable sortable"
! Name !! Battery !! WRAM !! Mirroring
|-
| Chibi Maruko-chan: Uki Uki Shopping || No || No || V
|-
| Dream Master || No || No || H
|-
| Family Circuit '91 || Yes || 2 KiB || V
|-
| Famista '91 || No || No || V
|-
| Heisei Tensai Bakabon || No || No || V
|}
===Namco 340 (Submapper 2)===
* Famista '92
* Famista '93
* Famista '94
* Splatterhouse: Wanpaku Graffiti
* Top Striker
* Wagyan Land 2
* Wagyan Land 3
 
== Banks ==
* CPU $6000-$7FFF: 2 KB PRG RAM bank, mirrored four times (Namco 175 only)
* CPU $8000-$9FFF: 8 KB switchable PRG ROM bank
* CPU $A000-$BFFF: 8 KB switchable PRG ROM bank
* CPU $C000-$DFFF: 8 KB switchable PRG ROM bank
* CPU $E000-$FFFF: 8 KB PRG ROM bank, fixed to the last bank
* PPU $0000-$03FF: 1 KB switchable CHR bank
* PPU $0400-$07FF: 1 KB switchable CHR bank
* PPU $0800-$0BFF: 1 KB switchable CHR bank
* PPU $0C00-$0FFF: 1 KB switchable CHR bank
* PPU $1000-$13FF: 1 KB switchable CHR bank
* PPU $1400-$17FF: 1 KB switchable CHR bank
* PPU $1800-$1BFF: 1 KB switchable CHR bank
* PPU $1C00-$1FFF: 1 KB switchable CHR bank
 
== Registers ==
The 175 and 340 have 12 registers within $8000-$FFFF. Each register occupies a range of $800 bytes, so $8000-$87FF all refers to one register, $8800-$8FFF all refers to another register, and so on.
 
=== CHR Select ($8000-$BFFF) w ===
{| class="wikitable"
! Value CPU writes !! Behavior
|-
| $00-$FF || Selects 1KB page of CHR-ROM
|}
{| class="wikitable"
! Write to CPU address !! 1KB CHR bank affected
|-
| $8000-$87FF || $0000-$03FF
|-
| $8800-$8FFF || $0400-$07FF
|-
| $9000-$97FF || $0800-$0BFF
|-
| $9800-$9FFF || $0C00-$0FFF
|-
| $A000-$A7FF || $1000-$13FF
|-
| $A800-$AFFF || $1400-$17FF
|-
| $B000-$B7FF || $1800-$1BFF
|-
| $B800-$BFFF || $1C00-$1FFF
|}
 
=== External PRG RAM enable ($C000-$C7FF) w (Namco 175 only) ===
7  bit  0
---- ----
.... ...E
        |
        +- 1: Enable PRG RAM
 
=== PRG Select 1 ($E000-$E7FF) w ===
7  bit  0
---- ----
MMPP PPPP
|||| ||||
||++-++++- Select 8KB page of PRG-ROM at $8000
++-------- Namco 340 only: Select mirroring
              0: One-screen A
              1: Vertical
              2: One-screen B
              3: Horizontal
 
=== PRG Select 2 ($E800-$EFFF) w ===
7  bit  0
---- ----
..PP PPPP
  || ||||
  ++-++++- Select 8KB page of PRG-ROM at $A000
 
=== PRG Select 3 ($F000-$F7FF) w ===
7  bit  0
---- ----
..PP PPPP
  || ||||
  ++-++++- Select 8KB page of PRG-ROM at $C000
 
==Notes==
* ''Family Circuit '91'' relies on its 2 KiB of WRAM being correctly mirrored throughout the $6000-$7FFF address range.
* Many INES Mapper 210 games are incorrectly set to [[INES Mapper 019]].
* In the absence of a NES 2.0 header with submapper 1 or 2 to distinguish between Namco 175 and 340, the following heuristics have been suggested:
** If $E000.6 or $E000.7 are ever set, this should be a Namcot 340.
** If the game ever reads from or writes to PRG RAM, this is a Namco 175 with external RAM.
** If the game ever writes to $C000, this is probably a Namco 175.
 
== See also ==
*[http://d.hatena.ne.jp/na6ko/20110501/1304181038 Naruko's blog's post on mirroring on the 340]
 
[[Category:ASIC mappers]][[Category:Mappers with single-screen mirroring]]

Latest revision as of 03:55, 10 February 2021

Namco 175
Company Namco
Games 4 in NesCartDB
Complexity ASIC
Boards 110F0B
PRG ROM capacity 512K
PRG ROM window 8Kx3 + 8K fixed
PRG RAM capacity 8K
PRG RAM window 8K
CHR capacity 256K
CHR window 1Kx8
Nametable mirroring H or V fixed
Bus conflicts No
IRQ No
Audio No
iNES mappers 210
Namco 340
Company Namco
Games 8 in NesCartDB
Complexity ASIC
Boards CS000x
PRG ROM capacity 512K
PRG ROM window 8Kx3 + 8K fixed
PRG RAM capacity none
PRG RAM window none
CHR capacity 256K
CHR window 1Kx8
Nametable mirroring H, V, or 1 switchable
Bus conflicts No
IRQ No
Audio No
iNES mappers 210

iNES Mapper 210 is used to denote Famicom boards bearing either the Namco 175 (Submapper 1) or Namco 340 (Submapper 2) ASIC. Both can be thought of as cost-reduced versions of the Namco 163:

Function N163 N175 N340
IRQ counter Yes No No
ROM nametables Yes No No
Optional WRAM Yes Yes No
Expansion audio Yes No No
ASIC-internal RAM Yes No No
Mirroring Selectable (extended) Hard-wired H/V Selectable H/V/0

Game list

Namco 175 (Submapper 1)

Name Battery WRAM Mirroring
Chibi Maruko-chan: Uki Uki Shopping No No V
Dream Master No No H
Family Circuit '91 Yes 2 KiB V
Famista '91 No No V
Heisei Tensai Bakabon No No V

Namco 340 (Submapper 2)

  • Famista '92
  • Famista '93
  • Famista '94
  • Splatterhouse: Wanpaku Graffiti
  • Top Striker
  • Wagyan Land 2
  • Wagyan Land 3

Banks

  • CPU $6000-$7FFF: 2 KB PRG RAM bank, mirrored four times (Namco 175 only)
  • CPU $8000-$9FFF: 8 KB switchable PRG ROM bank
  • CPU $A000-$BFFF: 8 KB switchable PRG ROM bank
  • CPU $C000-$DFFF: 8 KB switchable PRG ROM bank
  • CPU $E000-$FFFF: 8 KB PRG ROM bank, fixed to the last bank
  • PPU $0000-$03FF: 1 KB switchable CHR bank
  • PPU $0400-$07FF: 1 KB switchable CHR bank
  • PPU $0800-$0BFF: 1 KB switchable CHR bank
  • PPU $0C00-$0FFF: 1 KB switchable CHR bank
  • PPU $1000-$13FF: 1 KB switchable CHR bank
  • PPU $1400-$17FF: 1 KB switchable CHR bank
  • PPU $1800-$1BFF: 1 KB switchable CHR bank
  • PPU $1C00-$1FFF: 1 KB switchable CHR bank

Registers

The 175 and 340 have 12 registers within $8000-$FFFF. Each register occupies a range of $800 bytes, so $8000-$87FF all refers to one register, $8800-$8FFF all refers to another register, and so on.

CHR Select ($8000-$BFFF) w

Value CPU writes Behavior
$00-$FF Selects 1KB page of CHR-ROM
Write to CPU address 1KB CHR bank affected
$8000-$87FF $0000-$03FF
$8800-$8FFF $0400-$07FF
$9000-$97FF $0800-$0BFF
$9800-$9FFF $0C00-$0FFF
$A000-$A7FF $1000-$13FF
$A800-$AFFF $1400-$17FF
$B000-$B7FF $1800-$1BFF
$B800-$BFFF $1C00-$1FFF

External PRG RAM enable ($C000-$C7FF) w (Namco 175 only)

7  bit  0
---- ----
.... ...E
        |
        +- 1: Enable PRG RAM

PRG Select 1 ($E000-$E7FF) w

7  bit  0
---- ----
MMPP PPPP
|||| ||||
||++-++++- Select 8KB page of PRG-ROM at $8000
++-------- Namco 340 only: Select mirroring
             0: One-screen A
             1: Vertical
             2: One-screen B
             3: Horizontal

PRG Select 2 ($E800-$EFFF) w

7  bit  0
---- ----
..PP PPPP
  || ||||
  ++-++++- Select 8KB page of PRG-ROM at $A000

PRG Select 3 ($F000-$F7FF) w

7  bit  0
---- ----
..PP PPPP
  || ||||
  ++-++++- Select 8KB page of PRG-ROM at $C000

Notes

  • Family Circuit '91 relies on its 2 KiB of WRAM being correctly mirrored throughout the $6000-$7FFF address range.
  • Many INES Mapper 210 games are incorrectly set to INES Mapper 019.
  • In the absence of a NES 2.0 header with submapper 1 or 2 to distinguish between Namco 175 and 340, the following heuristics have been suggested:
    • If $E000.6 or $E000.7 are ever set, this should be a Namcot 340.
    • If the game ever reads from or writes to PRG RAM, this is a Namco 175 with external RAM.
    • If the game ever writes to $C000, this is probably a Namco 175.

See also

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