Re: [stella] 2600 Memory Map & Question

Subject: Re: [stella] 2600 Memory Map & Question
From: Eckhard Stolberg <Eckhard_Stolberg@xxxxxxxxxxxxxxxxxxxxx>
Date: Wed, 21 Jun 2000 19:31:47 +0200
At 00:25 21.06.2000 -0700, you wrote:
><EXTERNAL MEMORY>
>Atari 2600      ROM Memory Map
>
>E000-FFFF                             8K Rom
>(shouldn't this be EFFF-FFFF?  this is an 8K range above)

Actually it should be $F000-$FFFF as those are 4kb.

>1000-1FFF			4K Rom (mirror)
>3000-3FFF			4K Rom (mirror)
></EXTERNAL MEMORY>
>
>
>I am curious about something here.  The 6507 has a 13-bit address 
>bus.  This comes out to 8192 bytes linear addressable.  Don't these hex 
>values jump around too much to fit within that address space?

The 6507 has only 13 address bits on the outside, but on the inside
it uses 16 bits just like any other 6502. Since the top three address bits
don't have any pins to connect to on the outside of the 6507, you can
specify every address in eith different ways.


Ciao, Eckhard Stolberg



--
Archives (includes files) at http://www.biglist.com/lists/stella/archives/
Unsub & more at http://www.biglist.com/lists/stella/

Current Thread