[Coco] Re: OS-9 as Replacement for DECB

jdaggett at gate.net jdaggett at gate.net
Fri Sep 2 21:43:46 EDT 2005


Art

Currently in CB ver 1.2 there is 10 bytes free in that ROM space. In ECB version 
1.1 is no room
in SECB 
153 bytes from $C3C6 to C404
1019 bytes from $DC05 to $DFFF
1800 bytes from $C405 to $DC04 if you remove the authors picture, easter egg. 
In DECB 1.1you have 1686 bytes from $D900 to $DEFF and another 167 bytes 
from $DF59 to $DFFF.

By my count that is already 4835 bytes already free. I have no idea as to how much 
I could free up? I am not sure anyone knows. Maybe one byte and then maybe 1K. 

I do agree that the people at Microsoft were very creative in  how they coded the 
Color Basic and Extended Color basic. I did get fatigued in trying to follow the 
DLOAD code section. What a mess. Can it be fully understood? Yes if one  has 
time. Right now I have more time than money. At times my father thinks I spend to 
much time at the computer. Oh well. 

james





On 2 Sep 2005 at 18:33, Arthur Flexser wrote:

Date sent:      	Fri, 2 Sep 2005 18:33:36 -0400 (EDT)
From:           	Arthur Flexser <flexser at fiu.edu>
To:             	CoCoList for Color Computer Enthusiasts 
<coco at maltedmedia.com>
Subject:        	Re: [Coco] Re: OS-9 as Replacement for DECB
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> No doubt, a rewrite can indeed be done that eliminates backward
> compatibility.  But, if your purpose is to PRESERVE backward
> compatibility <grin>, you are screwed as far as saving appreciable ROM
> space.  The problem is the lack of documented vectors, and the
> consequent and understandable practice of ML software writers to use
> undocumented addresses scattered all over the ROM code.  And, of
> course, there exists no comprehensive list of such entry points.
> Getting ADOS to be as compatible as it is involved plenty of tracking
> down of reported software incompatibilities and correcting them one by
> one, even though ADOS was written as patched ROM code with a view
> towards being as compatibile as possible from the outset.
> 
> Art





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