Xref: utzoo comp.sys.amiga:37591 comp.sys.amiga.tech:6385
Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!cs.utexas.edu!usc!hacgate!gryphon!jdow
From: jdow@gryphon.COM (J. Dow)
Newsgroups: comp.sys.amiga,comp.sys.amiga.tech
Subject: Re: Need info on Partitions
Summary: Quite easy if you keep disk blocks straight
Message-ID: <18225@gryphon.COM>
Date: 30 Jul 89 12:50:22 GMT
References: <15745@ut-emx.UUCP>
Reply-To: jdow@gryphon.COM (J. Dow)
Distribution: na
Organization: Wizardess Designs, Hermosa Beach, Ca.
Lines: 58

In article <15745@ut-emx.UUCP> chm@ut-emx.UUCP (Christopher H. Marshall) writes:
>I would like to hear from anyone who has gotten a floppy-sized hard
>disk partition to work, especially with the Microbotics Stardrive.
>
>I tried to Mount such a partition on my StarDrive but always got guru
>#3.  Never made it to the formatting stage.
>
>Any suggestions or information would be appreciated.  E-mail, please.
>
>				Thanks,
>				Christopher Marshall
>				chm@emx.utexas.edu
>				cmft552@hermes.chpc.utexas.edu

This is quite easy Christopher if youkeep used disk blocks straight in the
mountlist. Remember that StarDrive, and indeed ALL trackdisk interfaces, think
in terms of offsets and byte counts. So when you setup your df4: partition
on the HD you must tell it to offset properly into the disk so that you do 
not run afoul of any other partitions.

If you have a HD that thinks in terms of 15 heads, 35 sectors per track, and 
1218 available cylinders and want to start things after your sys: partition
which is setup with Surfaces = 15, Blockspertrack = 35, and hicyl = 70 you
have to figure out that this means it uses disk blocks out to number 37275 or
so. Then you define your df4: partition. It should be set up such that its
first physical disk block begins at or beyond 37275. You cannot say locyl = 71.
If you do it'll think it should begin placing things on the disk at block 
71*11*2 = 1562 which will corrupt things in the sys: partition leading to a
visit to the man in the loin cloth who lives on the mountain top. You'd have
to tell it that lowcyl = 1695 or so.

Now whether or not this is useable is a different ball of hydrocarbons. DiskCopy
is too smart for its own good in regards to floppies and may not like to do a
diskcopy into that partition. And there is no help in sight as you will have to
start lowcyl at 1 for any partition in the near future if you want to upgrade to
a newer StarDrive device driver that will automount if not autoboot. (I *might*
even get a rad: like autoreboot in there but don't know for sure. If I do I am
quite sure that VirusX'd dislike it and complain about it.)

I hope this little disertation helps a bit. Thisis something I have never found
the need to do to myself. (I built a version of my ramdisk driver that could
recover itself and looked like a floppy disk enough that diskcopy was happy. 
And with four drives I understand Charlie Heath was able to run four diskcopy's
at once. I should spruce it up a little and post it someday. (Prolly onBIX...))
{@_@}


-- 
Sometimes a bird in the hand leaves a sticky deposit.
Perhaps it were best it remain there in the bush with the other one.

{@_@}
	jdow on bix (where else?)	Sometimes the dragon wins. Sometimes
	jdow@gryphon.CTS.COM		the knight. Does the fair maiden ever
	{backbone}!gryphon!jdow		win? Surely both the knight and dragon
					stink. Maybe the maiden should suicide?
					Better yet - she should get an Amiga and
					quit playing with dragons and knights.