[stella] chewing a unicycle

Subject: [stella] chewing a unicycle
From: "Andrew Davie" <adavie@xxxxxxxxxxxxx>
Date: Wed, 14 Feb 2001 00:29:36 +1100
Found myself needing to use up a single cycle.
For eg: in the following code, I have 4 cycles used.

   nop ;2
   nop ;2

If I was in tightly timed code, and wanted to do a store at that point, like

 sta COLUBK ;3
 ;one cycle extra needed to be used... how?

I've only used 3 cycles, which will stuff the timing of the code.  I need to
use another cycle.  The solution is to change the instruction you inserted,
or one earlier, to long addressing instead of zero page addressing.  I'm not
sure how to do that with DASM, but I simply looked up the opcode for the
long instruction and did it manually, like this....

  .byte $8D,COLUBK,0

This is effectively replacing the zero-page address refrence (3 cycles) with
an absolute address (4 cycles).
Thought this might help somebody, sometime :)


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