Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!swrinde!cs.utexas.edu!uunet!pcserver2!kdenning
From: kdenning@pcserver2.naitc.com (Karl Denninger)
Newsgroups: comp.unix.sysv386
Subject: Re: ESIX *does* support RLL (was Re: Does ESIX still not support RLL?)
Summary: This is so trivial to do that any Unix that doesn't is BROKEN!
Message-ID: <1991Apr28.024505.10968@pcserver2.naitc.com>
Date: 28 Apr 91 02:45:05 GMT
References: <78@overlf.UUCP> <1991Apr28.004009.17398@metro.ucc.su.OZ.AU>
Organization: AC Nielsen, Bannockburn IL USA
Lines: 32

In article <1991Apr28.004009.17398@metro.ucc.su.OZ.AU> glenn@suphys.physics.su.OZ.AU (Glenn Geers) writes:
>My primary hard disk and controller are an ST4144R disk and a WD-1006vsr2
>controller. The only trouble I've had is the notorious lock-up problem.
>I've cured this by formatting 2:1, so I lose a little speed but it's a 
>lot better than crashing (anyway I've got a 209 Mb SCSI as my other drive :-) ).
>ESIX does detect that the primary drive is RLL. That's ESIX rev. D - the only
>version I've used.

The "detection" in this case is simply looking in the BIOS DPB (disk
parameter block) after the self-test (or POST) has completed.

The disk parameters are in there.  Any OS which does this can easily
determine geometry on the fly.

One of my MAJOR complaints with Novell 2.x was that it didn't do that --
thus forcing you to either run with their idea of a "standard" disk drive or
buy a driver from someone.  Completely silly and outrageous.

Any 1003-compatible disk I/O board (MFM, RLL, ESDI) at the register level
which properly sets the DPB should work with most of the Unix releases out
there.  

I'd very much like to hear of any which don't look in the DPB, and instead
go directly to the ROMs (this is what Novell did).

--
Karl Denninger - AC Nielsen, Bannockburn IL (708) 317-3285
kdenning@nis.naitc.com

"The most dangerous command on any computer is the carriage return."
Disclaimer:  The opinions here are solely mine and may or may not reflect
  	     those of the company.