INES Mapper 036: Difference between revisions
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Mask: $E103 | Mask: $E103 | ||
write $4102 or $8000-$FFFF: [..PP ....] - Request 32 KiB PRG bank | write $4102 or $8000-$FFFF: [..PP ....] - Request 32 KiB PRG bank | ||
write $4100 then $8000-$FFFF: | write $4100: activate bankswitch to bitwise NOT of requested bank | ||
then write $8000-$FFFF (but only the first time): correct bankswitch without extra inversion | |||
read $4100: [..PP ....] - Return current 32 KiB PRG bank | read $4100: [..PP ....] - Return current 32 KiB PRG bank | ||
read or write others: ? | read or write others: ? | ||
This PRG reverse-engineering is confusing | This PRG reverse-engineering is confusing but mostly complete | ||
See also: | See also: | ||
* http://forums.nesdev.org/viewtopic.php?p=167180#p167180 Thread about dumping Policeman starts here | * http://forums.nesdev.org/viewtopic.php?p=167180#p167180 Thread about dumping Policeman starts here | ||
Revision as of 22:51, 3 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. Three games are currently known to use it, mostly published by Gluk Video:
- Strike Wolf
- Policeman
- F-15 City War (no ASIC)
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 (but only the first time): correct bankswitch without extra inversion read $4100: [..PP ....] - Return current 32 KiB PRG bank read or write others: ?
This PRG reverse-engineering is confusing but mostly complete
See also:
- http://forums.nesdev.org/viewtopic.php?p=167180#p167180 Thread about dumping Policeman starts here
