Talk:Errata: Difference between revisions
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== I don't understand this ceaveat == | |||
In horizontal or 4-screen mirroring, writing $2000 at the exact start of horizontal blanking may cause the PPU to start reading from the first pattern table instead of the second. | |||
(Workaround: Don't disable NMI during active picture. Instead, use a variable to lock out reentrant NMI.) | |||
Can someone rewrite it with a better wording so that non-native english speakers understand it ? | |||
[[User:Bregalad|Bregalad]] ([[User talk:Bregalad|talk]]) 05:12, 4 November 2013 (MST) | |||
Revision as of 12:12, 4 November 2013
Some things to add by people who know what these refer to:
PPU: must wait a couple of vblanks before chip is fully active
PPU: can't reliably write to ports more often than several CPU cycles apart
Page-crossing pointer quirks:
JMP ($nnnn)
($nn),Y
($nn,X)
I don't understand this ceaveat
In horizontal or 4-screen mirroring, writing $2000 at the exact start of horizontal blanking may cause the PPU to start reading from the first pattern table instead of the second. (Workaround: Don't disable NMI during active picture. Instead, use a variable to lock out reentrant NMI.)
Can someone rewrite it with a better wording so that non-native english speakers understand it ?
Bregalad (talk) 05:12, 4 November 2013 (MST)
