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 -- Archives updated once/day at http://www.biglist.com/lists/stella/archives/ Unsubscribing and other info at http://www.biglist.com/lists/stella/stella.html
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Re: [stella] $F000 or $1000 or what, Greg Miller | Thread | [stella] Doom for the Atari 2600, Jay |
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