File talk:Ntsc timing.png

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the first green ppu cycle 0 on the visible scanline 0 seems to be misleading. according to blargg's odd/even frame test, this skipped cycle should be arranged at the last ppu cycle of the pre-render scanline, and the idle cycle presented in the image should be a read (if odd + rendering enabled). --110.206.2.212 01:34, 10 December 2013 (MST)

  • One of the comments (at the lower-right) states that the skipped cycle is actually at y=261,x=340 (and circuit analysis confirms that this is when it happens); I'm not sure why it's shown the way it is on the diagram. --Quietust (talk) 05:23, 11 December 2013 (MST)
    • Might it have to do with the long-standing off-by-one error in cycle counts? --Tepples (talk) 06:28, 11 December 2013 (MST)
    • I think I drew it like that to avoid giving the impression that the final NT fetch on the pre-render line is skipped during odd frames. What really happens is that the final cycle of the fetch moves to (0,0), replacing the idle tick. Can't think of a non-convoluted way to express that in the diagram. --Ulfalizer (talk)