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 'PP' to internal register 'RR'. When M=1, RR=RR+1
 write $4101: no visible effect
 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.

The 05-00002-010 ASIC is connected as:

                .--\/--.
         ¹NC <- |01  24| -> NC¹
 (r) PRG A16 <- |02  23| -> NC²
 (r) PRG A15 <- |03  22| -> NC³
         GND ?? |04  21| <- CPU A13 (rn)
          5V ?? |05  20| <- CPU A14 (rn)
         ²NC <> |06  19| ?? GND
          5V ?? |07  18| <- CPU R/W (n)
         ²NC <> |08  17| <- /ROMSEL (rn)
         ²NC <> |09  16| <- M2 (n)
         ¹NC <> |10  15| <- CPU A8 (rn)
 (rn) CPU D5 <> |11  14| <- CPU A1 (rn)
 (rn) CPU D4 <> |12  13| <- CPU A0 (rn)
                '------'

 ¹: pins 1, 10, and 24 could respectively function as PRG A17, CPU D6, and PRG A18 if they were connected.
    PRG A18 can only be toggled, and that only by using the increment behavior
 ²: pins 6,8,9, and 23 could respectively function as CPU D0, D1, D2, and CHR A13 if they were connected;
    however writes to $4101 then cause extra obfuscatory behavior
 ³: Defective, always high


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: