INES Mapper 210

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
Family Circuit '91	Yes	2 KiB	V
Famista '91	No	No	V
Heisei Tensai Bakabon	No	No	V

Namco 340 (Submapper 2)

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

Banks

• CPU $6000-$7FFF: 8 KB PRG RAM bank (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 $4800-$4FFF all refers to one register, $5000-$57FF all refers to another register, and so on.

CHR and NT Select ($8000-$DFFF) 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
---- ----
M.PP PPPP
|||| ||||
||++-++++- Select 8KB page of PRG-ROM at $8000
++-------- Namco 340 only: Select mirroring
             0: One-screen A
             1: Vertical
             2: Horizontal
             3: One-screen B

PRG Select 2 / CHR-RAM Enable ($E800-$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 suggsted:
  • If $E000.7 is ever set, this should be a Namcot 340.
  • If $E000.6 is set, this is probably a Namcot 340.
  • If the game ever reads from or writes to PRG RAM, this is NOT a Namcot 340
  • If the game ever writes to $C000, this is probably a Namcot 175 with external RAM.