[net.micro.68k] Atari 520ST fact and fiction

jpm@bnl44.UUCP (John McNamee) (10/01/85)

[Since nobody has seen fit to create net.micro.st, and since this message
is sort of in reply to messages in many places, I have cross-posted to
many groups. Followups will go to net.micro.atari.]

I have seen a lot of the same misinformation passed around on the net
recently, and I would like to clear up a few things. I think I speak
from a position of authority as I am an ST developer, and have been
working with both Atari and Digital Research.

False:	The ST runs CP/M-68k.
True:	The ST runs the TOS operating system (the generic name is GEMDOS),
	which is not at all like CP/M-68K. There were some early plans to
	run CP/M, but they were dropped. GEMDOS can best be described as
	a 68000 version of MSDOS 2.0. It has almost all the same DOS calls
	as MSDOS (the function numbers are even the same), except CP/M
	style FCB's were dropped in favor of Unix style file handles.

False:	The ST hardware doesn't allow multitasking.
True:	There is nothing in the ST hardware to prevent multitasking. GEMDOS
	is a single tasking operating system, but there are already plans to
	port OS/9-68K to the ST, which will give it multitasking/multiuser
	capability. I bet Atari is also working on a multitasking OS of their
	own. DRI has already shipped Concurrent DOS 68000 to OEMs. In other
	words, it won't be long until the ST will multitask. I personally
	don't view this as a very important ability for most users, but I
	have already posted articles on that view and won't go into it here.

False:	The Amiga hardware has special provision for multitasking.
True:	The Amiga is not better than the ST when it comes to hardware support
	for multitasking. Neither has a real MMU (the ST has a chip called
	"MMU", but it does not offer full protection and relocation, and was
	not designed for multitasking). The Amiga DOS has built-in support for
	multitasking, so if you must have that ability right now then the
	Amiga is your only choice. Of course it does cost twice as much as the
	ST, so be sure you really need multitasking before buying.

False:	The ST talks to hard disks at 1 megabit per second, like the Mac.
True:	The ST talks to hard disks at over 1 megaBYTE per second, almost
	like Ethernet, and faster than an ST506 drive can deliver data. It
	also talks to floppies via a DMA channel, with all the work being
	done in hardware. The floppy controler is a standard Western Digital
	part which creates standard IBM format double density disks. There
	is no strange formatting or special drives.

False:	The Amiga graphics chips offload the CPU, but the ST does everything
	in software like the Mac.
True:	The ST has lots of custom chips, just like the Amiga.

False:	The Amiga is faster than the ST.
True:	The Amiga runs at a slower clock speed (7.2Mhz vs 8Mhz), and its
	graphics chips take over a larger percentage of bus bandwidth. In
	a CPU intensive task, the ST will win. I can't comment on graphics
	performance since I haven't had the chance to really get down and
	dirty with the graphics chips on either machine. It does seem that
	Amiga has spent a lot of time on neat looking graphics demos, while
	Atari has spent more time on making their OS work and on applications
	software. What this means is you can see lots of interesting graphics
	on an Amiga right now, while there isn't much yet on the ST.

False:	The Amiga can run a text based shell, but the ST can only run the
	mouse/window oriented desktop.
True:	This one is partly true. The Amiga is delivered with a text based
	shell (they call it the CLI), and the ST isn't. There actually is
	a standard shell for GEMDOS, but Atari does not provide it to end
	users. They used to provide it to developers, but they stopped that
	too. I hope they change their mind, becuase not everybody wants to
	deal with mice and windows. Even if Atari doesn't provide anything,
	there is nothing to prevent a third party from selling one. I know
	of one on the market already (it comes with the Haba Hippo C package),
	and there are at least two more on the way.

All in all, the ST is actually a very capable system at one hell of a price.
The Amiga is getting a lot of good press these days, and the ST is getting
very little press at all (good or bad), so many people are not taking a
serious look at the machine. The people at Atari tell me this will change
soon, as a number of magazines will run ST articles in the near future.
Everybody should take a serious look at both machines, and at their bank
balance, and decide which is best for them. I think most people will find
that the ST offers the greater value for the dollar.
-- 

			 John McNamee
		..!decvax!philabs!sbcs!bnl44!jpm
			jpm@BNL44.ARPA

		  "MS-DOS is a communist plot"