Re: [stella] Space Savers

Subject: Re: [stella] Space Savers
From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx>
Date: Fri, 3 Sep 2004 21:22:48 +0200
>     ORG $FFFC ;Reset vector
>     .WORD START-$1000 ;for 4K and $0800 for 2K ROM
>     SEI    ;first instructions of standard reset code
>     CLD
> ;^continue at start of rom ^

If you are setting up your reset vector like this, the
execution of code will start at $EFFE. $Exxx is not a mirror
of the game ROM. Only the odd 4K blocks ($Fxxx, $Dxxx, $Bxxx,
etc) are game ROM. The even 4K blocks ($Exxx, $Cxxx, $Axxx,
etc) contain mirrors of the TIA and RIOT registers. Therefore
your code would most likely crash.

Ciao, Eckhard Stolberg

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