CPU/PPU timing help wanted

Discuss hardware-related topics, such as development cartridges, CopyNES, PowerPak, EPROMs, or whatever.

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ulfalizer
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Joined: Fri Mar 08, 2013 9:55 pm
Location: Linköping, Sweden

CPU/PPU timing help wanted

Post by ulfalizer » Sat Apr 20, 2013 3:25 pm

Since people here might have relevant experience but might not browse nesemdev, please see viewtopic.php?f=3&t=10029#p111204 .

Basically it's unknown what happens when flags like VBL/sprite 0, etc. are read at different master clock offsets from where the flag changes (blargg's test roms only test CPU behavior in a relative fashion and do not nail down the exact timing), meaning there's still a bit of fudging and guesswork. :/

Might want to reply in that thread if you're interested to avoid the discussion getting spread out. Excuse the spam. :wink:

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