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punesemu / puNES

Qt-based Nintendo Entertaiment System emulator and NSF/NSF2/NSFe Music Player (Linux, FreeBSD, OpenBSD and Windows)
GNU General Public License v2.0
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Mapper 422 ( and variants): At least 1 cart has broken graphics #367

Closed negativeExponent closed 5 months ago

negativeExponent commented 5 months ago

2024-01-30T13:05:18,523239303+08:00

chr needs updating: https://www.nesdev.org/wiki/NES_2.0_Mapper_534 rom for convenience (just remove when your done with test): (AB-199) AB 一簇 10-in-1.nes.zip

negativeExponent commented 5 months ago

it appears that the update broke some mapper 422 boards and both in 126(there's only 2 carts). so not sure what NRS' notes about this change since its already on nesdev.

the specific issue is inverting bit5 of register 0

punesemu commented 5 months ago

Thanks for the report, I missed the note on bit 5. You are right by inverting bit 5 there are problems with the chr in some dumps 422 and the two 126 but it could depend on what is reported in the note on nesdev Older dumps do not take this inversion into account..

negativeExponent commented 5 months ago

ic. i missed that last note of the inverted bit (took the glance, never read it whole). thanks for the clarification. so older dumps are bad then.

punesemu commented 5 months ago

I have integrated the inversion of bit 5 by disabling it for the old dumps in order to still make them playable.