Some pipes lead to weird non-rooms in Super Mario Bros.

Discuss emulation of the Nintendo Entertainment System and Famicom.

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lidnariq
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Re: Some pipes lead to weird non-rooms in Super Mario Bros.

Post by lidnariq » Wed Jan 08, 2020 6:30 pm

op9C is a cryptic thing that is very awkward to use intentionally. It's "supposed" to be STY abs,X, except that the architects at MOS forgot about it, so it generates a bunch of glitchy internal bus conflicts instead of writing Y to the correct location. See this post and the next couple posts.

It's hard enough to use I'd be surprised if any software uses it intentionally, but maybe someone figured out something useful it could do on the 2600.

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