Date   : Sun, 14 Jun 1992 18:48:59 +1200
From   : julian <julian@...>
Subject: Re: Screen memory

RWF Whitehand <R.W.F.Whitehand1@...> writes:

> Erm, it won't be used if you use software scrolly, etc. as he suggests
> later on in his message...however, I'm not into arcade games in Mode 7 :-)

I think that's a pity. In mode 7 you have the potential for *very* large
sprites moving around quickly. You also have heaps of memory left over to
make a much more involved arcade game than has ever been seen before on
a 32k machine. Certainly there are complications with the use of colour,
but it's not an insoluble problem, and even lack of colour never stopped
games like Starship Command, Plan B and Aviator from becoming popular...

> Its use is a little restricted...esp. as it probably gets cleared after a
> CLS (quicker for the OS to clear in sensible junks, I'm sure) and is
> 'miles' away from other useful RAM, etc. anyway.

In 6502 code it doesn't matter where the ram is in relation to your code,
you can still reference it with a single instruction. Also one of the
reasons I brought it up was because someone mentioned getting their
programs to work/download properly from ADFS, and in at least one case
the only way I was able get get a program to work from ADFS was to put the
download routine in that memory (I think, or it might have been the Basic
stack). The program was loaded at PAGE and corrupted about 90% of the
mode 7 screen... there was virtually nowhere else to put the download code!

    Cheers, Julian.
--
wright_j@...                |---------------------| "I'm sig of sicknatures!"
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