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sarospa / arachNES

"Average NES emulator contains 3 spiders" factoid actually just statistical error...
GNU Affero General Public License v3.0
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full_palette.nes: Emulator halts on bad PPU address #5

Open sarospa opened 7 years ago

sarospa commented 7 years ago

Immediately upon attempting to boot this ROM, the emulator halts and reports an access to out-of-range address 433F.

sarospa commented 7 years ago

Upon deeper investigation, it appears that this ROM behaves very strangely in FCEUX. It looks alright in BizHawk though. Is there something wrong with this ROM? This problem may be difficult to diagnose if two high-quality emulators disagree on how it should function.

sarospa commented 7 years ago

It seems as though this ROM uses a carefully cycle-timed routine with no interrupts in order to display the full range of colors. It's no wonder my poor emulator couldn't handle this. It'll be a good long while before I have any hope of getting this right, but it'll be an interesting test if I can. It looks like I was right, though, and FCEUX can't handle this sort of thing either.