Will all (most) DDS-4 tape drives work on a narrow (50-pin) single ended
SCSI bus?

Most drives seem to be Ultra wide, but Sun 390-0028 (option 6295)

http://sunsolve.sun.com/handbook_pub..._40GB_4mm.html

whilst having a 68-pin connector, has the wide SCSI bus disabled.

From the Sun website:

390-0028
HP C5683-00625
***Wide SCSI Disabled***
Medium Grey Bezel
Option 6295

So it seems this unit (which is an HP drive badged as Sun) has wide
SCSI disabled. Will a typical DDS-4 tape drive work on narrow SCSI, or
does one has to be a special one?

There appears to be no jumper on that drive, so I'm not so sure most
drives could be used.

The original poster of this thread

http://groups.google.co.uk/group/com...344ceff3c244ee

was told to use his drive on narrow bus, but I'm not so sure it will
work (I've obviously dropped him an email to ask).

Theres one or two of that part number on eBay
http://cgi.ebay.com/HP-C5683-00625-2...QQcmdZViewItem
http://cgi.ebay.com/HP-C5683-00625-2...QQcmdZViewItem

but at between $550 and $780, they are very expensive, given the DDS-4
drives have sold for $60, and perhaps less.
http://cgi.ebay.com/DELL-DDS-4-DAT-4... cmdZViewItem



--
Dave K

http://www.southminster-branch-line.org.uk/

Please note my email address changes periodically to avoid spam.
It is always of the form: month-year@domain. Hitting reply will work
for a couple of months only. Later set it manually. The month is
always written in 3 letters (e.g. Jan, not January etc)

Dave (from the UK) wrote:
> Will all (most) DDS-4 tape drives work on a narrow (50-pin) single ended
> SCSI bus?
>
> Most drives seem to be Ultra wide, but Sun 390-0028 (option 6295)
>
> http://sunsolve.sun.com/handbook_pub..._40GB_4mm.html
>
>
> whilst having a 68-pin connector, has the wide SCSI bus disabled.
>
> From the Sun website:
>
> 390-0028
> HP C5683-00625
> ***Wide SCSI Disabled***
> Medium Grey Bezel
> Option 6295
>
> So it seems this unit (which is an HP drive badged as Sun) has wide
> SCSI disabled. Will a typical DDS-4 tape drive work on narrow SCSI, or
> does one has to be a special one?
>
> There appears to be no jumper on that drive, so I'm not so sure most
> drives could be used.
>
> The original poster of this thread
>
> http://groups.google.co.uk/group/com...344ceff3c244ee
>
>
> was told to use his drive on narrow bus, but I'm not so sure it will
> work (I've obviously dropped him an email to ask).
>
> Theres one or two of that part number on eBay
> http://cgi.ebay.com/HP-C5683-00625-2...QQcmdZViewItem
>
> http://cgi.ebay.com/HP-C5683-00625-2...QQcmdZViewItem
>
>
> but at between $550 and $780, they are very expensive, given the DDS-4
> drives have sold for $60, and perhaps less.
> http://cgi.ebay.com/DELL-DDS-4-DAT-4... cmdZViewItem
>
>
>
>
I have a number of DDS3 drives running off a mix of Sun (HD50), PC and
Mac machines. I don't know if DDS4s use the same connector on the actual
drive units, but given the speed and data throughput of the media, I
can't see the point of enforcing a faster standard so I'm guessing that
DDS4 drives, unhoused at least, will hook up fine...??? Pure hypothesis
though as I've no real experience.

FWIW, I've found the Sony 9000 DDS3 machines to be vastly superior to
the HP stuff etc. I their DDS4 drive is an 11000 but again, that's from
(failing) memory, not knowledge.

Good luck. Hopefully others here will have more informed knowledge...

John

In comp.sys.sun.hardware "Dave (from the UK)" <see-my-signature@southminster-branch-line.org.uk> wrote:

> So it seems this unit (which is an HP drive badged as Sun) has wide
> SCSI disabled. Will a typical DDS-4 tape drive work on narrow SCSI, or
> does one has to be a special one?

I would expect most devices of proper voltage to work properly on a
slow, narrow bus as long as the extra pins are properly terminated.

The device should detect the connection parameters and back down to
match.

I don't know why the Sun part would have a device with the wide SCSI
disabled in a narrow housing, unless they were expecting it in the
application and terminated the "wide" pins themselves within the unit.
(That way your 68-50 pin cable doesn't have to have any smarts).

--
Darren Dunham ddunham@taos.com
Senior Technical Consultant TAOS http://www.taos.com/
Got some Dr Pepper? San Francisco, CA bay area
< This line left intentionally blank to confuse you. >

Darren Dunham wrote:
> In comp.sys.sun.hardware "Dave (from the UK)" <see-my-signature@southminster-branch-line.org.uk> wrote:
>
>
>>So it seems this unit (which is an HP drive badged as Sun) has wide
>>SCSI disabled. Will a typical DDS-4 tape drive work on narrow SCSI, or
>>does one has to be a special one?
>
>
> I would expect most devices of proper voltage to work properly on a
> slow, narrow bus as long as the extra pins are properly terminated.
>
> The device should detect the connection parameters and back down to
> match.
>
> I don't know why the Sun part would have a device with the wide SCSI
> disabled in a narrow housing, unless they were expecting it in the
> application and terminated the "wide" pins themselves within the unit.
> (That way your 68-50 pin cable doesn't have to have any smarts).
>

Thanks. This may not be necessary after all. I think I can use a
standard 68-pin tape drive, although that is far from easy.



Having take the Ultra 80 apart and looked at the SCSI in some detail,
what I see is a cable that goes to a disk backplane at one end and the
CD-ROM and the other. I think that cable is probably 68-conductors,
although I have not counted.

Just to make life difficult, there are two problems.

1) The end that goes onto the disk backplane looks as though it can not
be removed. Not sure, but I don't fancy pulling it hard enough to find out.

2) The back of the bit that goes into the CD-ROM has some sort of
terminator. I think that probably terminates the high byte. Again, am
not 100% sure.

I think putting a 68-pin connector on that cable will allow me to attach
a standard 68-pin tape drive, but I'm not over happy about it. The cable
is short, and one end is fixed, so clamping a connector properly looks
to be difficult.

I really need to find out how the tape drive is supposed to be attached,
and if a cable can be bought. I don't fancy messing around with the only
cable I have, given I have not seen one like it before.

--
Dave K

http://www.southminster-branch-line.org.uk/

Please note my email address changes periodically to avoid spam.
It is always of the form: month-year@domain. Hitting reply will work
for a couple of months only. Later set it manually. The month is
always written in 3 letters (e.g. Jan, not January etc)