14 Apr
2003
14 Apr
'03
7:08 p.m.
Hmm...
If they're FAT16 (2.1Gb max recognition), maybe you can get hold of an old
copy of Partition Magic, and see if you can read them with it.
Its doubtful that the drives are physically harmed, but the 0 Sector (boot
and/or reference sector) will be different with each version of DOS you try.
If you can boot from floppy, you may want to reformat the disks (DOS 2.11,
or 3.20) and start anew. Do you know what they likely contain? Are they
worth the time/effort to recover as-is?
Cheers...
Ed Tillman
Store Automation Tech Support Specialist
Valero Energy Corporation
San Antonio, Texas, USA
Office: (210)592-3110, Fax (210)592-2048
Email: edward.tillman(a)valero.com <mailto:edward.tillman@valero.com>
-----Original Message-----
From: Alan Greenstreet [mailto:aeg@paradise.net.nz]
Sent: Saturday, April 12, 2003 10:55 PM
To: cctalk(a)classiccmp.org
Subject: HH drives
Hi All
I have a newbie question <collective groan from list>
I don't have much experience with HH type drives and recently unearthed
a Wyse Technologies machine at the local refuse recycling centre (it's
a shop rather than me wading though a landfill site - I'm not that
desperate).
Inside this machine (stated built in 1986) were two HH type 5.25" hard
drives (one a Segate ST-251 the other not branded but built 1989).
On boot up I get:
Pheonix 80386 ROM BIOS version 3.53
(c) 1985, 1986 Pheonix Technologies Ltd
640K Base 1408K Extended Memory
Hard Disk Failure
I have booted the system using a floppy and one drive (the unbranded
one) is partially readable.
It is a 41Mb drive split into two partitions (primary & extended) -
FAT16 system
It seems to have been installed with DRDOS.
Using my later versions of DOS on floppy I cannot get the drive to
respond to any standard commands (I always get a 'Sector not found'
error).
Can anything be done to revive these disks or were they left unparked
and now physically damaged?
I have another 5.25" hard drive displaying the same unresponsive
characteristics... are they all dead?
Thanks in advance
Alan
15 Apr
15 Apr
9:50 p.m.
On Tuesday, Apr 15, 2003, at 19:05 Pacific/Auckland, Tillman, Edward
wrote:
Hmm...
If they're FAT16 (2.1Gb max recognition), maybe you can get hold of an
old
copy of Partition Magic, and see if you can read them with it.
It's a possibility, another list member is trying to dig out an old
Wyse set-up disk, this may also do the trick.
Its doubtful that the drives are physically harmed, but the 0 Sector
(boot
and/or reference sector) will be different with each version of DOS
you try.
If you can boot from floppy, you may want to reformat the disks (DOS
2.11,
or 3.20) and start anew. Do you know what they likely contain? Are
they
worth the time/effort to recover as-is?
They have a version of DRDOS and whilst this is hardly irreplacable I
don't currently have a copy. I'd also like to gain a little more
experience with this type of drive. I've tried DOS 2.11, 3.21 and 3.30
(and even 4.1, 5.0 and 6.22). With all versions one of the disks is not
recognised at all (this could be another fault all together). At the
end of the day I'm more curious than desperate.
Thank you all who replied to this post for all of the hints and tips
Alan
16 Apr
16 Apr
6:44 a.m.
New subject: FAT16 2G trivia (was: HH drives
> If they're FAT16 (2.1Gb max recognition),
maybe you can get hold of an
Would 65535 be considered to be 65.5K here?
How many bytes are in a K? M? G?
The maximum size for most FAT16 partitions is 2147483647, which is 2 to
the 31st power minus 1, or 2 HONEST Gigabytes (minus 1). The size limit
is due to the use in MS-DOS of a long int, which is a 32 bit signed
number. A long int has a range from -2147483648 to 2147483647. That was
an error; they should have used a UNSIGNED long int (0 to 4294967295)
The long int is also used for file size. Thus, for many versions of
MS-DOS, the range of file sizes is also -2147483648 to 2147483647. One
time, when the free space on one of my hard drives was getting sparse, I
took a floppy disk and stepped on one of the directory entries to give it
a reported file size of -2147483648. Then I tried to copy that negative 2
gig file to the hard drive. What effect should there be on free space if
you add a file with a negative size? It didn't work. What was even more
fun was trying to explain to the MICROS~1 "Beta team" management why
things like file size should be unsigned.
In NT (not sure if ALL versions), they switched from a long int to an
unsigned long int (which it should have been from the get go). Because of
that, a FAT16 partition in NT can be up to 2 to the 32nd power minus one,
4294967295, or FOUR HONEST/binary gigabytes (minus one byte). But those
partitions are only readable by NT, since MS-DOS (and WINDOZE9x) sees them
as having a negative size.
--
Grumpy Ol' Fred cisin(a)xenosoft.com
7921
days inactive
7922
days old
2 comments
3 participants
participants (3)
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aeg＠paradise.net.nz -
cisin＠xenosoft.com -
Edward.Tillman＠valero.com