I was describing the activity on the PPU's external video memory bus. You're describing the activity on the internal OAM bus. Both appear correct to me.Zepper wrote:My notes are a bit different... but from the wiki anyways.tepples wrote:257-260: Dummy nametable fetch. A12 is low
261-264: Sprite pattern fetch (1 of 8). A12 is high
265-268: Dummy nametable fetch. A12 is low
269-272: Sprite pattern fetch (2 of 8). A12 is highIs this incorrect?
Code: Select all
/* Cycles 257-320: Sprite fetches (8 sprites total, 8 cycles per sprite) * 0-3: Read the Y-coordinate(0), tile number(1), attributes(2), and X-coordinate(3) of the selected sprite from secondary OAM. * 4-7: Read the X-coordinate of the selected sprite from secondary OAM 4 times (while the PPU fetches the sprite tile data). * For the first empty sprite slot, this will consist of sprite #63's Y-coordinate followed by 3 $FF bytes; for subsequent empty sprite slots, this will be four $FF bytes. */