At 10:31 AM 3/6/01 +0100, you wrote:
Hi again,
here is another example of an usefull illegal opcode: NOP!
However, there are a lot of branches (2 bytes) which can be easily
replaced with BIT (1 byte):
Now that is neat! A couple of questions...
The only problem is, that BIT changes flags (V,N,Z) which are sometimes
needed later. But there is an illegal opcode solution for that: NOP.
To replace BIT ABS (opcode $2c) you can use $0c (NOP ABS). Here is an
example from my Thrust code:
What does "ABS" mean? I apologize in advance if that's painfully obvious
and I'm missing it.
.byte $0c ; <-- here I use an illegal NOP because I
need the overflow- and negative-flags!
How many cycles do these two commands take? Looks like it's nearly time to
update Nick's cycle counting paper.
Thanks for the neat trick!
Ruffin Bailey
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