Re: [stella] Atari memory

Subject: Re: [stella] Atari memory
From: Thomas Boutell <boutell@xxxxxxxxxxx>
Date: Tue, 1 Mar 2005 13:39:42 -0500
On Tue, 1 Mar 2005, Paul Slocum wrote:

>
>> No, but it does have 64K of address space.
>
> if it were a 6502, but the 6507 can only address 8K (only 13 address
> lines).  So the top 3 MSBs of the address are ignored on the 2600 (which
> effectively creates a mirror every 8K).
>
> so if you're ever REALLY short on memory and are using pointers in RAM, you
> can use those top 3 bits for something.  ;o)

Oops, yes, 13 lines, which explains why the 128B of RAM and 128B of
hardware registers don't conflict with the 4K of ROM as they would
with only 12... right?

--
Thomas Boutell
Boutell.Com, Inc. 
http://www.boutell.com/


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