Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!lll-winken!uunet!tektronix!psueea!psueea.uucp!kirkenda
From: kirkenda@psueea.uucp (Steve Kirkendall)
Newsgroups: comp.os.minix
Subject: Re: Info on Atari ST
Message-ID: <1071@psueea.UUCP>
Date: 23 Apr 89 22:25:20 GMT
References: <3748@sdsu.UUCP> <2905@sun.soe.clarkson.edu>
Sender: news@psueea.UUCP
Reply-To: kirkenda@jove.cs.pdx.edu (Steve Kirkendall)
Distribution: usa
Organization: Dept. of Computer Science, Portland State University; Portland OR
Lines: 88

In article <2905@sun.soe.clarkson.edu> jk0@sun.soe.clarkson.edu (Jason Coughlin) writes:
>	Could someone please email a few specs on the Atari ST?  I'm
>considering buying one and the ST Minix.

  There seems to be a lot of new interest in Minix, especially on the ST,
  so I guess the answers are worth posting...

>	(A) How much memory can be put in the sucker?

  Four megabytes, without resorting to funny hardware hacks.  The Atari
  addresses two banks of 16 chips; each bank can be composed of either 256k
  chips or 1M chips, so to have more than 1 meg or RAM, you must use the
  1M chips, which are still kinda spendy.

>	(B) Does it have protection hardware?

  A little, but not enough.  A user process can't access the lower 2k (or so)
  of RAM, so an attempt to dereference a NULL pointer is trapped.  Also, user
  processes can't access I/O ports, and nothing can access non-existent
  memory.  However, there is nothing to prevent a user process from zapping
  some other user process, or even most of the kernel.

>	(C) What is the max size of a process under Minix?

  Limited only by available memory.  Figure about 150k for the kernel, and
  about 250k for the RAM disk.  My system has 1 meg or RAM, of which 550k is
  "available", and I routinely run processes that need over 400k.

>	(D) What HD, CRT would you suggest?

  You should allow at least 15 megabytes for Minix.  It will fit in half that
  much space (complete with source), but you want to allow room for your own
  stuff, too...  As for a particular brand of HD, well, every brand has its
  fanatics.  Some people have had trouble with Atari Megafile 60's.

And from other messages:

What can I do with Minix? What is it for?

  Minix is a case-study, presented in Andy Tannenbaum's textbook,
  "Operating Systems - Design and Implementation".  You can use Minix to
  learn about operating systems.  If you don't want to learn about OSes,
  then tere is little reason for you to get Minix.

Does it Multitask like OS-9?

  Yes.  Minix seems somewhat faster (really!) and much more reliable than
  OS-9, and you get source code and a compiler, for a lot less money.

Can I run Atari ST programs on it?

  No.  But you can partition your hard disk and use one prtition for GEM
  and the other for Minix, so it's not all-or-nothing.

Are all the UNIX goodies there?

  No, but a lot of them are, and a lot of P.D. stuff is being ported and
  posted.  Conspicuously absent from the standard Minix-ST are:
	vi	- a PD version called "stevie" has been ported.
	uucp	- a PD version called "uupc" is being ported.
	rcs or sccs
	floating point - I think GCC (a PD compiler) has floats
	lex & yacc - the GNU versions have been ported, I think.
  Also, the versions of commands that you do get are generally pretty limited.
  E.g., `ls` can't list filenames in multiple columns, and `tar` can't split
  archives across multiple volumes.  Fortunately, we all have source code...

How fast is Minix?

  Compared to what?  The compiler is slow, but not prohibitively so.  System
  calls have a high overhead, but that really only affects unbuffered I/O.
  Minix is fast enough to be useful, but nobody is going to say "Wow! Look
  at that thing go!"

How similar is Minix to Unix?

  It's easy to port programs from Unix to Minix.  Minix is meant to resemble
  version 7 Unix.  Version 7 was the last common ancestor between BSD 4.3 and
  System V.  Generally, it is easier to port BSD programs than SysV programs,
  because SysV uses a different set of ioctl() calls for controlling
  the console and serial lines.

  The internal structure of the Minix kernel is entirely different from that
  of any "real" Unix system.  Unix was written for efficiency; Minix was
  written for understandability and ease of modification.

-- Steve Kirkendall
   uunet!tektronix!psu-cs!kirkenda