INES Mapper 162

iNES Mapper 162 denotes the 外星 (Wàixīng) FS304 circuit board, used for the following games:

• Mummy - 神鬼传奇
• Zelda 传说: 三神之力 (ES-1096)
• 法老王 - Pharaoh (ES-1114)
• 火焰纹章 - 圣战的系谱 and its title screen hack 聖火徽章 III (Shènghuǒ Huīzhāng III/Fire Emblem III)
• 西游记后传 (ES-1097)

A compatible circuit board with an unknown PCB code is used for a few games from 南晶 (Nánjīng):

• 梁山英雄 (Liángshān Yīngxióng, NJ023, title screen hack of 水浒神兽, NJ019)
• 时空斗士 - Pegasus Senya (Shíkōng Dòushì, NJ024, title screen hack of 圣斗士星矢: 天马之幻想, NJ022)
• 农场小精灵 (Nóngchǎng Xiǎojīnglíng, NJ025, title screen hack of 牧场物语 - Harvest Moon, NJ011)

Banks

• CPU $6000-$7FFF: 8 KiB unbanked PRG-RAM, battery-backed
• CPU $8000-$FFFF: 32 KiB switchable PRG-ROM bank
• PPU $0000-$1FFF: 8 KiB unbanked CHR-RAM bank, 4 KiB can be automatically switched
• Nametable mirroring: hard-wired

Registers

All registers are initialized to $00 on reset.

PRG-ROM Bank Low/CHR-RAM Switch ($5000, write)

Mask: $FF00

D~7654 3210
  ---------
  C... PPpq
  |    |||+- PRG A15 if $5300.0=1 and $5300.2=1
  |    ||+-- PRG A16 if $5300.2=1
  |    ++--- PRG A18..A17
  +--------- Automatic 4 KiB CHR-RAM switch: when PPU A13=0 (pattern table) ...
              0: CHR A12=PPU A12 (disable auto-switch)
              1: CHR A12=PPU A9 latched on last rise of PPU A13 (enable auto-switch)

Automatic 4 KiB CHR-RAM switch means that the left pattern table is used for the the top half of any nametable, and the right pattern table for the bottom half of any nametable, regardless of the scroll position. This auto-switch behavior is similar to that of mapper 96.

Alternative PRG-ROM Bank low ($5100, write)

Mask: $FF00

D~7654 3210
  ---------
  .... ..p.
         +-- PRG A15 if $5300.0=0

PRG-ROM Bank High ($5200, write)

Mask: $FF00

D~7654 3210
  ---------
  .... ..PP
         ++- PRG A20..A19

Mode ($5300, write)

Mask: $FF00

D~7654 3210
  ---------
  .... .A.B
        | +- PRG A15 mode:
        |     0: PRG A15=$5100.1
        |     1: PRG A15=1       if A=0
        |        PRG A15=$5000.0 if A=1
        +--- PRG A16 mode:
              0: PRG A16=1
              1: PRG A16=$5000.1

Or in terms of where PRG A15-16 come from:

$5300.2/0   PRG A16   PRG A15
-----------------------------
      0.0      1      $5100.1
      0.1      1         1
      1.0   $5000.1   $5100.1
      1.1   $5000.1   $5000.0

Because reset clears all registers' bits, games will boot in 32 KiB PRG-ROM bank #2 (A16=1 and A15=$5100.1=0).

Notes

• To ensure that a cartridge to be dumped is really INES Mapper 162, write $04 to $5300 and verify that $5100.1 changes the PRG bank.
• The Waixing games run with $5300=$04, using $5100.1 to change PRG A16. The two Nanjing games run with $5300=$07, using $5000.0 to change PRG A16, except for a protection check shortly after the title screen where the described behavior of $5300=$04 is verified.

See also

Similar mappers: INES Mapper 163, INES Mapper 164, NES 2.0 Mapper 558