Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!husc6!uwvax!geowhiz!uwspan!root
From: root@uwspan.UUCP (Sue Peru Sr.)
Newsgroups: comp.unix.microport
Subject: Re: Microport System V/386 install woes
Message-ID: <3879@uwspan.UUCP>
Date: 24 May 88 20:00:21 GMT
References: <1984@sugar.UUCP> <26531@clyde.ATT.COM> <1101@ddsw1.UUCP>
Reply-To: plocher@uwspan.UUCP (John Plocher)
Followup-To: comp.unix.microport
Organization: U of Wisconsin - Madison  Spanish Department
Lines: 48

+---- Karl Denninger writes in <1101@ddsw1.UUCP> ----
| How many of you out there have a *reliable* system with Microport and the
| Seagate 80M drives? (ST4096 -- 9 heads, 1024 cyls).
| 
| We found that this drive *requires* that you set one of the HD options,
| "Control byte", to 8 (default is zero) or the drive will fail at an
| indeterminate time in the future (usually within 48 hours).
| 
| Uport doesn't allow changing this parameter.  I assume the ROM value is
| used -- which is normally zero!
| 
| This is the one place where Microport's "dynamic disk configuration" seems 
| to be missing something -- in this case, vital information.
| 
| Karl Denninger
+----

Karl,
    Uport doesn't let users change this parameter, because the parameter's
value can be determined from what you enter for the number of heads.  If the
number of heads is <= 8, the CB is set to 0, but if the number of heads is
( 8 < HEADS <= 16 ) then the CB is set to 8, just like the doctor ordered.

I have the V/AT sources to the programs which do this (fdisk & cousins) and
this is indeed what the code does.  For V/AT 286 2.3 (I don't know (or really
care) about versions before this, since there is no reason to not upgrade
since the kernel and drivers are cleaner in 2.3 than in 2.2...).

Also for V/386 users there is a new hard disk driver on the BBS which
supports RLL, ESDI, etc drives with more than 8 heads and more than 17 SPT.
Apparently the current version of V/386 has some limitations in it
(I wasn't able to find out just what, but the new driver *is* on the BBS)

Version V/386 3.0 ("out in a few weeks") will have a new HD driver with these
things included.

  -John 

PS:  For you trivia buffs,

	The WD1002 can only handle up to 1024 cyls,
	the WD1003 can handle up to 2048.
	The V/AT 2.3 driver can only handle up to 1024.

What are the features/limits on the other HD controllers out there?

-- 
Comp.Unix.Microport is now unmoderated!  Use at your own risk :-)