Re: [stella] $F000 or $1000 or what?

Subject: Re: [stella] $F000 or $1000 or what?
From: Eckhard_Stolberg@xxxxxxxxxxxxxxxxxxxxx (Eckhard Stolberg)
Date: Thu, 4 Sep 1997 17:00:09 +0200
>It seems to be the standard for Atari 2600 code
>to run from $F000 - $FFFF... I've read that this
>is actually the same as addressing $1000, $3000,
>and so on.  Is there any problem with assembling
>code to, say, $1000?  Will it run on the SC just
>as well as if it was assembled to $F000?
>Because the 6507 is missing some addressing lines,
>does the memory map truly just go from $0000 to
>$1FFF?  I'd find that alot easier to cope with :)
>I'm used to having the full 64K addressable...
>uniquely addressable, I guess.

The 6507 doesn't care for the missing address lines. Address $1000 is the
same as $F000 to it. It just seem to be a standart in VCS programming to
set all unused bits to 1.

Also due to the bankswitching combinations that the SC allows it is easyer
to position the first bank at $D000 or $D800 before banks 2 and 3 at $F000.
That way you can have all three banks in one source code.

Ciao, Eckhard Stolberg

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