14 Aug
2012
14 Aug
'12
12:58 p.m.
From: Dave McGuire
Sent: Tuesday, August 14, 2012 1:33 AM
On 08/14/2012 04:06 AM, TeoZ wrote:
> There was a brief hop to just differential SCSI
(higher voltage then
> LVD which is how LVD got its name). HVD and SE/LVD don't like each
> other while the other SCSI standards did with some tweeking.
This overlapped entirely with SE SCSI to the end,
though. HVD was
used in very high-end machines (Tandem and Cray come to mind) for the
better noise immunity for longer cable runs. It really wasn't a hop
from SE to HVD then to LVD.
Also the XKL Toad-1 System (4 x differential FASTWIDE SCSI-2 ports).
An absolute bear to find drives for.
Rich Alderson
Vintage Computing Sr. Systems Engineer
Vulcan, Inc.
505 5th Avenue S, Suite 900
Seattle, WA 98104
mailto:RichA at vulcan.com
mailto:RichA at LivingComputerMuseum.org
http://www.LivingComputerMuseum.org/
1:26 p.m.
On 08/14/2012 03:58 PM, Rich Alderson wrote:
I have a very large quantity of 68-pin HVD 4.3GB drives. Contact me
off-list.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
> There was
a brief hop to just differential SCSI (higher voltage then
> LVD which is how LVD got its name). HVD and SE/LVD don't like each
> other while the other SCSI standards did with some tweeking.
This overlapped entirely with SE SCSI to the
end, though. HVD was
used in very high-end machines (Tandem and Cray come to mind) for the
better noise immunity for longer cable runs. It really wasn't a hop
from SE to HVD then to LVD.
Also the XKL Toad-1 System (4 x differential FASTWIDE SCSI-2 ports).
An absolute bear to find drives for. 
6:21 p.m.
I have a very large quantity of 68-pin HVD 4.3GB
drives.
I have a ridiculous number of HVD SCSI SBus cards; if anyone needs such
a thing, just let me know.
Now, all we need is someone with too many HVD terminators... :)
/~\ The ASCII Mouse
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5:13 p.m.
What kind of internal termination do you need for HVD drives anyway? I have
4 HVD drives but no idea how to terminate them (I assume normal 68 pin LVD
cables with terms are a no go).
----- Original Message -----
From: "Rich Alderson" <RichA at vulcan.com>
To: "'General Discussion: On-Topic and Off-Topic Posts'"
<cctalk at classiccmp.org>
Sent: Tuesday, August 14, 2012 3:58 PM
Subject: HtG differential SCSI [was RE: To all with interest in IBM 7090]
From: Dave McGuire
Sent: Tuesday, August 14, 2012 1:33 AM
On 08/14/2012 04:06 AM, TeoZ wrote:
> There was a brief hop to just differential
SCSI (higher voltage then
> LVD which is how LVD got its name). HVD and SE/LVD don't like each
> other while the other SCSI standards did with some tweeking.
This overlapped entirely with SE SCSI to the
end, though. HVD was
used in very high-end machines (Tandem and Cray come to mind) for the
better noise immunity for longer cable runs. It really wasn't a hop
from SE to HVD then to LVD.
Also the XKL Toad-1 System (4 x differential FASTWIDE SCSI-2 ports).
An absolute bear to find drives for.
Rich Alderson
Vintage Computing Sr. Systems Engineer
Vulcan, Inc.
505 5th Avenue S, Suite 900
Seattle, WA 98104
mailto:RichA at vulcan.com
mailto:RichA at LivingComputerMuseum.org
http://www.LivingComputerMuseum.org/
5:45 p.m.
On 08/14/2012 08:13 PM, TeoZ wrote:
What kind of internal termination do you need for HVD
drives anyway? I
have 4 HVD drives but no idea how to terminate them (I assume normal 68
pin LVD cables with terms are a no go).
There are special HVD terminators. I don't know if LVD terminators
will work, but I doubt it.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
5:57 p.m.
----- Original Message -----
From: "Dave McGuire" <mcguire at neurotica.com>
To: "General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
Sent: Tuesday, August 14, 2012 8:45 PM
Subject: Re: HtG differential SCSI [was RE: To all with interest in IBM
7090]
On 08/14/2012 08:13 PM, TeoZ wrote:
I have external HVD terminators (for an IBM mammoth tape drive), just never
seen an internal cable with one on it or I just never noticed it.
What kind of internal termination do you need for
HVD drives anyway? I
have 4 HVD drives but no idea how to terminate them (I assume normal 68
pin LVD cables with terms are a no go).
There are special HVD terminators. I don't know if LVD terminators
will work, but I doubt it.
-Dave
4512
days inactive
4513
days old
6 comments
5 participants
participants (5)
-
aek＠bitsavers.org -
mcguire＠neurotica.com -
mouse＠Rodents-Montreal.ORG -
RichA＠vulcan.com -
teoz＠neo.rr.com