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
  • 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]
                   |||| ||||
                   ||++------ reads show the internal state.
                   ++---++++- open bus
 write $4100: when M=0, copy PP to RR. When M=1, RR=RR+1
 write $4101: no visible effect
 write $4102: [..PP ....] - Request 32 KiB PRG bank
 write $4103: [...M ....] - PRG banking mode (0: copy, 1: increment)
 write $8000-$FFFF: copy 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| -> NC
 (r) PRG A16 <- |02  23| -> NC
 (r) PRG A15 <- |03  22| -> NC
         GND ?? |04  21| <- CPU A13 (rn)
          5V ?? |05  20| <- CPU A14 (rn)
          NC <> |06  19| ?? GND
          5V ?? |07  18| <- CPU R/W (n)
          NC <> |08  17| <- /ROMSEL (rn)
          NC <> |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 and 10 could respectively function as PRG A17 and CPU D6 if they were connected
    However, none of pins 6, 8, or 9 behave like CPU D7. Perhaps they were intended for CHR banking?

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: