At 5:14 PM +1100 3/8/01, Andrew Davie wrote:
>That's a pretty neat trick, Russ.... you can drop the clc and replace the
>first rol by an asl (saving a byte, and 2 cycles)
OOooo, I like that...
> lda FrameCounter
> asl
> rol
> rol
> sta FrameCounter
>
>I think, though, that we should count the extra cycles to trim off the low
>bits and transfer to an index register
Damn! I knew I forgot something... At first I thought I could do it
with just two ROLs, but then you have to preserve the carry, which
doesn't cut it.
>- the table lookup is a clear winner
Yeah, appears to be. I can't think of anything smaller at the moment.
>when this is taken into account. But still, your idea... at just 7 bytes...
>very impressive!
But you're doing that AND a lot to mask the high 6 bits, so...
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