----- Original Message -----
From: Glenn Saunders <cybpunks@xxxxxxxxxxxxx>
To: <stella@xxxxxxxxxxx>
Sent: Wednesday, April 26, 2000 5:08 AM
Subject: Re: [stella] Hardware comparisons
> I think video DMA on the Atari cuts raw throughput of the CPU down by
> 1/3rd, which is why there is a poke you can do to turn off video DMA when
> you are running a big numbercrunch operation. A lot of Atari BBS
operators
> would do that. The Atari 1200XL had that assigned to one of its function
keys.
ANTIC DMA only consumes 1/3 of the bus bandwidth in the 8K display modes
(8-11). In the text-based modes the impact is practically negligible.
> It actually cuts throughput enough to hinder playing digital samples,
> actually, which is why sampling programs (or software voice synths like
> SAM) would blank the screen.
Actually sampling (and playback) programs turn off *everything* that would
disturb the data stream... video DMA, the vertical blank interrupt, anything
else they can get their bits on...
I only remember four Atari games that played digital sound without killing
the screen-- Kennedy Approach, Whomper Stomper, Alley Cat, and MegaBlast (I
think that's the name).
--
Clay Halliwell | ATARI XL/XE DO + THE
clay.FAKEMEAT.h@xxxxxxx | 8 - B I T S --------
e.halliwell@xxxxxxxxx | /////////// M A T H
Keeper of the Atari Jaguar Cheats and Codes FAQ. Request your copy today!
Editor, Jaguar Explorer Online - More Jaguar News Than Should Be Allowed!
http://www.atarihq.com/jeo/ "Where do you want to play Atari today?"
--
Archives (includes files) at http://www.biglist.com/lists/stella/archives/
Unsub & more at http://www.biglist.com/lists/stella/
