Hello,people.I want to confirm some points.
What's happened if you write $2003 during the sprite evaluation phase?
Nestopia has
So it seems to me nothing happened.
Does it already know whether $2003 is used as internal index register?
Wiki says
This is not happening when forced blanking,isn't is?
What's bumping?Does it mean [n+1]?
Does it always occur or only does when OAMADDR=$Xxx11?
Sorry to bother you again.
What's happened if you write $2003 during the sprite evaluation phase?
Nestopia has
Code:
oam.address
which is different from Code:
regs.oam
(OAMADDR).So it seems to me nothing happened.
Does it already know whether $2003 is used as internal index register?
Wiki says
Quote:
OAMADDR is set to 0 during each of ticks 257-320 (the sprite tile loading interval) of the pre-render and visible scanlines.
This is not happening when forced blanking,isn't is?
Quote:
Writes to OAMDATA during rendering (on the pre-render line and the visible lines 0-239, provided either sprite or background rendering is enabled) do not modify values in OAM, but do perform a glitchy increment of OAMADDR, bumping only the high 6 bits (i.e., it bumps the [n] value in PPU sprite evaluation - it's plausible that it could bump the low bits instead depending on the current status of sprite evaluation).
What's bumping?Does it mean [n+1]?
Does it always occur or only does when OAMADDR=$Xxx11?
Sorry to bother you again.