PowerPak: Difference between revisions

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(adding information about newer mappers (WIP))
m (Rainwarrior moved page Buggy PowerPak Mappers to PowerPak: We need an article about the PowerPak itself, moving this while I update it with more info)

Revision as of 06:50, 29 July 2015

PowerPak emulates mappers used in NES games, but not always perfectly.

Power Mappers

TheFox created a set of revised PowerPak mappers to supplement or augment the existing ones, most notably adding a savestate feature.

Download: [1]

Loopy's Mappers

Loopy released a set of revised PowerPak mappers in 2011, adding fixes and additional support for a several mappers:

Download:https://home.comcast.net/~olimar/NES/powerpak_loopy.zip

CNROM, MMC3, FDS, NSF, VRC4, VRC6, N106, Sunsoft-5B, BxROM, Codemasters, Mapper 90 (partial), MMC5 (partial)

Problems in Offical Mappers V1.34

To do.

Fixed in Mappers V1.11

 iNES 4 - MMC3 - fixed bad irq
 iNES 9 - MMC2 - fixed bad chr switch
 iNES 64 - Rambo 1 - mostly fixed bad irq
 iNES 119 - TQROM (MMC3 + 74HC32) - fixed bad chr switch

iNES 3 - CNROM and clones - limited CHR size

CNROM supports up to four banks (32 KiB) of CHR ROM. PowerPak uses the bank number mod 4. This breaks Panesian games that use a compatible board that supports larger CHR ROMs but is otherwise functionally identical to CNROM.

iNES 4 - MMC3 - no wram disable

Older versions of MMC3 would corrupt PRG RAM when turning IRQs on or off because writes to $E000-$FFFF also went to $6000-$7FFF.

Low G Man needs WRAM disabled. There are two ways to disable it, but the PowerPak supports neither.

  • Low G Man disables WRAM during its startup code by writing a value less than $80 to $A001. But the PowerPak's MMC3 ignores $A001 writes entirely as a hack that lets it run StarTropics, whose MMC6 has a different disable method.
  • NES 2.0 allows specifying no WRAM at all, but the PowerPak ignores all additional NES 2.0 fields.

iNES 5 - MMC5 - known bad

Games will not start, mapper not complete yet.

iNES 71 - Camerica

Micro Machines has major graphics problems, could be FPGA pins are wrong.

Fire Hawk and Fantastic Adventures of Dizzy show the same problem.

Many of these are very likely bad roms.