while ( *( (unsigned char *)(0xD40B))) might work too.
But I'm confused - if you are drawing graphics in a normal way, outside of the vertical blanks, then you are by definition not going to be drawing them while the vb is happening, so there's no point in waiting. Any cycles your program gets are always 'after the Vblank', right? Unless the goal is to draw a complete screen before the next vblank happens...?
Anyway, I don't really understand what he's trying to do, so I'm probably off base.
Sanny - I didn't really give him a solution, just showed some examples of how to use a little bit of inline assembler to handle interrupts. He's asking for something else i think.
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