Talk:Init code

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Revision as of 18:09, 28 May 2015 by Rainwarrior (talk | contribs) (Prophylactic read of $2002)
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Prophylactic read of $2002

Is this bit of code necessary? I'm having trouble finding any original NES game that does it. Are there any known examples of a startup problem caused by this?

; Clear the vblank flag, so we know that we are waiting for the
; start of a vertical blank and not powering on with the
; vblank flag spuriously set
bit $2002

If it isn't a problem, does anyone have an explanation as to why it isn't? If it is, can anyone point to an example of the problem? (Maybe I'll write a test if I have time later...) - Rainwarrior (talk) 12:09, 28 May 2015 (MDT)