Re: [stella] standard ASM syntax

Subject: Re: [stella] standard ASM syntax
From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx>
Date: Thu, 18 Jan 2001 22:08:22 +0100
> I took a look at the alpha code and I noticed a couple things.  It used a
> VCS2600 header instead of vcs.h and it had a couple different equates for
> the console switches vs. vcs.h.  It also didn't have the processor 6502
> directive and was ORGed at $1000 vs. $F000.
>
> This caused a little trouble getting it to assemble.  I guess it's no big
> deal if I look for that in the future with sourcecode that gets posted to
> the list, but I was wondering...
>
> Have we all settled on a standard header file syntax yet?  I was thinking
> that everyone is using the VCS.h referencing in how to draw a
> playfield.  Shouldn't we standardize?

I think you are referring to Erik's RPG kernel source here, right?
That was written a long time ago before we silently agreed on a defacto
standard for posting source code.

The VCS only has 13 address lines, so $1000 and $F000 is the same
when programming on the VCS. There is no need to change the ORGs.

When you include the header file in all your source code files
anyway, you can just put the 'processor 6502' directive in there too.
I think this is what Erik did. You can even put it in both, the header
file and the game source code file. Usually this doesn't cause any
problems as long as you specify the same processor in both files. ;-)

I didn't see any strange equates for the console switches in Erik's
code. SWCHA, SWACNT and SWBCNT are defined like this in Steve Wright's
Stella programmer's guide. The files that came with Atari's ST based
development system use CTLSWA and CTLSWB instead of SWACNT and SWBCNT
though. But you can define both terms in your vcs.h file and use
them as synonyms. Then you shouldn't have problems anymore with assembling
sources from different programmers.

And if stuff like this already confuses you, you probably wouldn't
want to look at Erik's code. (or mine, for that matter) ;-)


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