Re: [stella] chewing a unicycle

Subject: Re: [stella] chewing a unicycle
From: Chris Wilkson <ecwilkso@xxxxxxx>
Date: Tue, 13 Feb 2001 10:17:23 -0500
In message <012b01c095c1$03b0a970$0100a8c0@screamer>, "Andrew Davie" writes:

>If I was in tightly timed code, and wanted to do a store at that point, like
>this...
>
> sta COLUBK ;3
> ;one cycle extra needed to be used... how?

>  .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 :)


Andrew,

You can also just use the TIA mirror at $100-$13F:

sta $109 3 ; stores to COLUBK mirror at $109

I have complete VCS memory maps available at
http://web.mit.edu/ecwilkso/www/VCS_hardware/

-Chris

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