Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!cs.utexas.edu!wuarchive!uunet!iphase!lawson
From: lawson@iphase.UUCP (David Lawson PER )
Newsgroups: comp.periphs.scsi
Subject: Re: Upgrade ST-02 to 1542B => re-partition drive?
Message-ID: <249@iphase.UUCP>
Date: 24 Sep 90 03:30:24 GMT
References: <1990Sep21.191238.23217@cimcor.mn.org>
Reply-To: lawson@iphase.UUCP (David Lawson PER )
Organization: Interphase Corp. Dallas TX
Lines: 18

In article <1990Sep21.191238.23217@cimcor.mn.org> dick@cimcor.mn.org (Dick Schlotfeldt) writes:
>I used MS-DOS 3.3 fdisk and format to partition and format a Wren IV
>with an ST-02 SCSI host adapter in a 12 MHz 286 machine. The partitions
>were C (boot), D, E, and F. It worked fine.
>
>After moving the disk drive to a 25 MHz 386 machine I tried booting with
>an Adaptec 1542B adapter. The SCSI bios found the drive (id 0) but
What is probably happening is that the different boards' BIOS extensions
handle drive geometry in different manners.  What will happen, since DOS
talks to the BIOS in cylinders, heads, and sectors, the BIOS has to translate
this to a logical address for SCSI.  Some boards will assume a specific
geometry of the drive, say 16 heads, 32 sectors per track, and vary the
number of cylinders according to the size of the drive.  The next board may
assume its own geometry which would cause problems if they do not match.

The only solution is to completely back up the drive with the original
controller and then set it up again with fdisk on the new controller and
restore the files.