Re: [stella] Reflex: Yeah! Skipdraw incorporated!

Subject: Re: [stella] Reflex: Yeah! Skipdraw incorporated!
From: "Thomas Jentzsch" <tjentzsch@xxxxxx>
Date: Mon, 06 Sep 2004 11:23:07 +0200
David wrote:
> If you build reflex75.asm with -lreflex75.lst (generate a listing file) 
> then you can inspect what was generated for the SLEEP macro. (I've 
> removed some of the macro syntax for clarity)
>      12  f099               24 00              bit    VSYNC

If you would allow illegal opcodes, this would look like this:
>      12  f099               24 00              nop    VSYNC

And there would be no problem. :-)

> If you really wanted to save a byte I think you could cook up something 
> in the 7 bytes that kills the 13 cycles and reliably sets the flags. For 
> instance you could remove the bit VSYNC and replace it with a LDA zpage 
> and then load from a known constant (or known non-zero) and do a bne...

That's something which should be done at the *end* of programming, when
you start optimizing for space.

Have fun!
Thomas Jentzsch         | *** Every bit is sacred ! ***
tjentzsch at web dot de |
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