INES Mapper 036: Difference between revisions
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[[Category:iNES Mappers|036]][[Category:GNROM-like mappers|036]] | [[Category:iNES Mappers|036]][[Category:GNROM-like mappers|036]] | ||
[[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 | [[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, [http://glukvideo.info/listado-juegos-gluk both published by Gluk Video]: | ||
* Strike Wolf | * Strike Wolf | ||
* Policeman | * Policeman | ||
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write $4100: activate bankswitch to bitwise NOT of requested bank | write $4100: activate bankswitch to bitwise NOT of requested bank | ||
then write $8000-$FFFF: correct bankswitch without extra inversion | then write $8000-$FFFF: correct bankswitch without extra inversion | ||
read $4100: [..PP ....] - Return current 32 KiB PRG bank | read $4100-4103: [..PP ....] - Return current 32 KiB PRG bank | ||
write others: ? | |||
There are bus conflicts on writes to $8000-$FFFF. | There are bus conflicts on writes to $8000-$FFFF. | ||
Revision as of 18:02, 26 April 2016
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, both published by Gluk Video:
- 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 write $4102 or $8000-$FFFF: [..PP ....] - Request 32 KiB PRG bank write $4100: activate bankswitch to bitwise NOT of requested bank then write $8000-$FFFF: correct bankswitch without extra inversion read $4100-4103: [..PP ....] - Return current 32 KiB PRG bank write others: ? There are bus conflicts on writes to $8000-$FFFF.
This PRG reverse-engineering is confusing but mostly 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:
- http://forums.nesdev.org/viewtopic.php?p=167180#p167180 Thread about dumping Policeman starts here
