Hi Eric,
> The key is the NOP_W, which is an equate for $0C, which is the opcode
NOP
> abs. (An illegal/undocumented version of NOP.
> The other advantage is this routine is always the same number of
cycles.
I know he uses NOP_W to get constant cycles. What I didn't see was how y
and yPosP0 are set before coming into the kernel. He has it set it such
a way that y is the correct value to load the graphics.
As Manuel pointed out, it's how the graphics data is setup in ROM and
how yPosP0 is calculated.
Take care,
Dennis
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