[A83] Re: Optimizing
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[A83] Re: Optimizing
And on the 86, the actual routine is on page 0, called directly from page D.
So you have two calls and the push/pop to take into account. But there are
very, very few instances where a few t-states are going to make any
difference. Only inside a sprite or tilemap drawing routine, but I can't
see doing 16 bit compares in there. Or inside a 3D engine (I remember that
being an issue when Clem ported Maze3D to the Game Boy, since all it's
instructions are 8 bit). But on the calculator, especially the 83, that
extra byte of RAM is more important than a few cycles.
> I was talking about the sequence "OR A \ SBC HL, DE", which
> takes three bytes, just like a single CALL instruction. And
> it's certainly faster than calling the actual CPHLDE rom
> routine. Forget about counting clocks, it makes no sense to
> say things like a CALL takes 17 clocks, because a
> subroutine contains at least some sort of return...
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