INES Mapper 036

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iNES Mapper 036 is assigned to TXC's PCB 01-22000-400, featuring a 74138, a 74175, and usually a 24-pin ASIC labeled 05-00002-010. Two games are currently known to require this definition.

  • Strike Wolf (also released as Comando de Lobos)
  • Policeman

Even though these games can evidently be emulated as a weird kind of GNROM, the hardware does something quite different:

The CHR banking is definitely implemented using the two 7400-series ICs:

Mask: $E200
write $4200: [.... CCCC] - Select 8 KiB CHR bank

The PRG banking is part of the ASIC:

Mask: $E103
 read $4100-4103: [xxRR xxxx]
                   |||| ||||
                   ||++------ Copy internal register 'RR' to data bus.
                   ++---++++- open bus
 write $4100: when M=0, copy internal register (when I=0) 'PP' or (when I=1) '~PP' to internal register 'RR'. When M=1, RR=RR+1
 write $4101: [...I ....] - Invert bit
 write $4102: [..PP ....] - Copy data bus to internal register 'PP'. Value is not yet exposed anywhere.
 write $4103: [...M ....] - PRG banking mode (0: copy, 1: increment)
 write $8000-$FFFF: copy internal register 'RR' to PRG banking pins

This PRG behavior is confusing but seems to be complete.

Three additional games published by Gluk use the same PCB, with no ASIC. They were also released in other regions on different hardware, and only Gluk's editions are compatible with the above-mentioned CHR banking.

  • F-15 City War
  • Volley ball
  • Puzzle

Compatibility code left in means that all editions of these three games are emulatable as NINA-06.

See also: