🚀 go-pugleaf

Well, there was an Amiga at our (somewhat sucessful) computerfest today,
sponsored by the University Personal Computing Assoc. (of which I am
an officer)  as well as 5 or 6 ST's and a lot of demos, so I'd like
to expand on some of this discussion. 
 
GG:	...Unless the ST has some sort of dual-ported RAM, the screen data
	must come from the same data bus in the ST as well.

JD:	..First, there are a pair of chips working together to optimize
	data bus and screen data access. The memory controller
	prefetches 16-bit data directly for the 68000 and also places
	screen data onto a separate bus for the screen refresh chip. This
	operation only steals 8-18% of the available true CPU time.

GG:	If you measure a computer's worth by the number of chips,
	you might as well pick an IBM over a Mac. Perhaps the custom chips
	in the AMIGA are  better integrated to perform several functions in one
	chip. Thus you do not need MORE chips if three can do the job. 

GF:	non sequatur (sp?)

myself: Regardless of the memory arrangement, I found the ST's graphics to
	appear intrinsically clearer.  Perhaps Atari uses a better monitor,
	or maybe they tighten up the dot edges, but the amiga's graphics
	had a fuzzier, blurrier, yet warmer appearance.  For data, I would
	have gone with the Atari's no-nonsense display, but the Amiga DOES
	do an impressive job on pre-drawn graphics, and the color text 
	display is less objectionable than Atari's.  As for the chips, well,
	maybe the IBM DOES have more chips than a Mac, or than the //e, but
	remember...all those PALs and semicustom gate arrays DO replace lots
	of so-called-glue.  Remember how Apple's MMU and IOU replace some
	140-odd chips?  And since when did manufacturers stop bragging about
	how many gates and transistors they've packed into the latest design?

JD:	The windows are poorly configured and move with flicker.

GG:	They do? Not in my AMIGA. 

GF:	Maybe they do in his AMIGA.

myself: They sure didn't in the Amiga at the 'fest.  In fact, I was very 
	impressed (in terms of graphics power) when, while running the
	'robo-city' demo (two characters and a dog walk across the
	screen behind an animated hydrant) the person at the Amiga 
	'grabbed' the entire page and slid it off the bottom of the screen
	while the demo was running.  No flicker.  No redrawing.  In fact,
	the demo kept running at the same pace while we ran its window
	all over the place.  Very nice, but there was severe flicker on 
	horizontal white lines in 640x400 mode, and while not apparent in
	solid areas, a violent flicker appeared in heavily colored/dithered
	spots on some screen captured shots.  No, I don't mean slightly grey
	edges.  The dots literally shook.  

caveats...the salesman tried to explain that the system unit had 512k in it,
	but he included the ram in the kickstart.  Unlike the Atari, when you
	get your system roms, you'll find yourself back to 256k.  Because they
	won't build the extra in after it's served its usefulness.  Also, the
	much-ballyhooed bouncing ball demo, although fun to look at, was not
	that impressive.  The 'thud' sound probably contributed to 60% of the
	effect, simply because it sounded massive.  But the shadow and ball
	both moved on the same path, at fixed velocity, and the only surface
	animation was a set of checkerboard bands rotating constantly on the
	ball.  Reminded me of a Mindset without flicker.  The Atari booth,
	on the other hand, showed some simpler, safer graphics, but then
	again, what do you use real-time graphics for?  I found the Atari
	to be adequate (and very cheap).

overrunning my expected line-limit,
-dave
-- 
-------------------------------------------------------------------------------
David Hsu						hsu @ eneevax.umd.edu
Communications & Signal Processing Laboratory		hsu @ sphinx.ee.umd.edu
Department of Electrical Engineering			hsu @ mit-prep.arpa
University of Maryland					hsu @ umd2.arpa

"You see?  You SEE???"