Sprite Overflow Flag Test ROMs

Discuss emulation of the Nintendo Entertainment System and Famicom.

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blargg
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Post by blargg »

Disch wrote:The problem is... blargg's demo wasn't reading $2002 during the frame, so my time was never being predicted. $2002 wasn't being read until the next VBlank -- by which time my emu thought it was too early to predict anything (too early in the current frame).
Ahhhh. That would be a good test for the emulator-specific ones I'm developing. A simple fix for the above is to "read" $2002 just before the end of the frame but without any of the usual side-effects that would usually occur. Your design seems sound to me. If I make progress on a lot of trick emulator-specific tests then you can put it to the test. I'm about to examine my design and come up with things to try to trick it.

UPDATE: I rewrote many of the tests and added a few more general ones, and added three emulator-specific tests. They should give more precise problem reports now, even if an emulator is really broken. Same archive location as the original:

sprite_overflow_tests.zip
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FitzRoy
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Re: Sprite Overflow Flag Test ROMs

Post by FitzRoy »

Does anyone have the 41kb versions of these tests? At some point, blargg rewrote most of his test roms to output descriptions of failures rather than codes that correspond to a text file. These are some of the only tests I haven't found modern versions of.
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