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Last updated on Oct-18-2019 Download

vram writes

vram writes
by on (#13525)
would writing to a name table not currently being rendered cause glitches? or do all writes to vram durring non-vblank time cause errors?

by on (#13526)
I think they'd be causing errors, since the PPU itself is messing around with the VRAM address while it renders.

by on (#13527)
Yeah, the register used to access PPU memory (accessed through $2006) is used during rendering. Anything you do with it during rendering will mess the current display and you'll probably not suceed on what you were trying to do.

by on (#13528)
It doesn't matter which nametable (or pattern table) is being accessed - the fact that one is being accessed at all means you cannot mess with $2006/$2007 during rendering without causing problems.