Path: utzoo!yunexus!geac!syntron!jtsv16!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!nosc!ucsd!sdcc6!sdcc12!mp1
From: mp1@sdcc12.ucsd.EDU (Leroy Dorman)
Newsgroups: comp.unix.microport
Subject: Re: ad-hominem attacks go to hell
Summary: stupid hardware, stupid software
Keywords: uport SV/286
Message-ID: <1031@sdcc12.ucsd.EDU>
Date: 12 Aug 88 01:47:05 GMT
Article-I.D.: sdcc12.1031
References: <531@micropen>
Organization: University of California, San Diego
Lines: 41

In article <531@micropen>, dave@micropen (David F. Carlson) writes:
> 
> There is no doubt that the Intel 80286 processor in the IBM PC/AT environment
> is a son-of-a-gun to support. 

The operative word is 'IBM PC/AT environment'. I've run 80286's
on Multibus I (THE porting base for V/286) with few problems.

> small 64K kernel stack and a very expensive context switching mechanism
> makes for real headaches in the serial device drivers.  I have looked at
> the serial device driver code and have wrung my hands at the double panics
> but it is a rock and a hard place situation--no one wins.  At 9600 baud
> you will have an interrupt every millisecond.  The service routine for pushing

I've eaten 19200Kb sustained rate (no handshaking!!) into an
Intel smart serial board to Unix V/286 (using a general purpose
terminal driver) and didn't lose a character. I only had 1Mb or
ram and 1K kernel stack. Smart hardware wins again.

> David F. Carlson, Micropen, Inc.
> micropen!dave@ee.rochester.edu

Regardless, John, I suspect, will do a kick-a** job just as he
always has. No one has a right to fault him for things not under
his control.

As far as V/AT goes, running it on an AT is probably more
trouble than it's worth. I've been running V/286 from the
release tape on Multibus I with MUCH more stability that an AT.
Don't know why . . . (actually, I do. Stupid H/W vs. Smart H/W)


Eric Dorman				Inch by painful inch
University of California, San Diego	    toward a better tomorrow
Scripps Institution of Oceanography	        -Me
 siolmd!eric@sdsioa.ucsd.edu
 mp1@sdcc12.ucsd.edu  Attn: eric
 dorman@mplvax.nosc.mil  Attn: eric

Disclaimer:
	Just because I think this way doesn't mean anyone else
does.