21 Apr
2008
21 Apr
'08
8:37 a.m.
Sorry if this has been asked before...
I have a few spare TK50 drives, and wondered if
these could be interfaced in some way to a regular
Linux box.
I know the PDP's use a special interface card, but
I seem to recall it was some kind of SCSI variant.
My reason for interfacing is that I have a few
TK50's on PDP 11's and it would be useful to
be able to transfer software.
Ian.
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21 Apr
21 Apr
8:52 a.m.
--- silvercreekvalley <silvercreekvalley at yahoo.com>
wrote:
Sorry if this has been asked before...
I have a few spare TK50 drives, and wondered if
these could be interfaced in some way to a regular
Linux box.
I know the PDP's use a special interface card,
but
I seem to recall it was some kind of SCSI variant.
It's a special interface, and you're not going to be
able to build just a simple adapter cable. But, they
DID make a SCSI TK-50. I have one, and I have used it
with Linux. The SCSI TK-50 drive is an external box
with a standard TK-50 mechanism and a special
controller/interface board that controls the drive and
groks SCSI back to the computer. Even then, it's not
the greatest SCSI tape drive interface, but it will
work.
One thing you have to remember to do though, is to
turn on the buffer. The drive doesn't have one.
mt -f /dev/nst0 drvbuffer 1
If you don't do this, the drive will shoeshine for an
hour writing even a small file...
-Ian
11:43 a.m.
Ian wrote:
But, they DID make a SCSI TK-50.
The TK50Z. DEC used "Z" to designate SCSI, though on later products it
was the second letter rather than a suffix. The TK50Z which came in -FA
and -GA variants with different firmware. The SCSI command set
implementation is atrocious; it will work with some host systems and not
others. IIRC, the -GA was much closer to meeting the SCSI spec.
In 2001, Pete Turnbull posted here that the firmware for the -GA is
a 27C256 with DEC part number 23-261E6.
There was also a TZ30.
12:06 p.m.
On Apr 21, 2008, at 2:43 PM, Eric Smith wrote:
The TK50Z. DEC used "Z" to designate SCSI,
though on later
products it
was the second letter rather than a suffix. The TK50Z which came
in -FA
and -GA variants with different firmware. The SCSI command set
implementation is atrocious; it will work with some host systems
and not
others. IIRC, the -GA was much closer to meeting the SCSI spec.
In 2001, Pete Turnbull posted here that the firmware for the -GA is
a 27C256 with DEC part number 23-261E6.
It might not be a bad idea for someone to archive that ROM image.
Does anyone have one handy?
-Dave
--
Dave McGuire
Port Charlotte, FL
12:28 p.m.
On 21/04/2008 20:06, Dave McGuire wrote:
On Apr 21, 2008, at 2:43 PM, Eric Smith wrote:
> The TK50Z. DEC used "Z" to designate SCSI, though on later products it
> was the second letter rather than a suffix. The TK50Z which came in -FA
> and -GA variants with different firmware. The SCSI command set
> implementation is atrocious; it will work with some host systems and not
> others. IIRC, the -GA was much closer to meeting the SCSI spec.
> In 2001, Pete Turnbull posted here that the firmware for the -GA is
> a 27C256 with DEC part number 23-261E6.
Did I? One list I have says 23-453E6 for the -GA and 23-254E6 for the
-FA. At least I got the 27C256 part right, but I wonder where I found
23-261E6...
It might not be a bad idea for someone to archive
that ROM image.
Does anyone have one handy?
http://www.dunnington.u-net.com/public/DECROMs/23-453E6.bin
--
Pete Peter Turnbull
Network Manager
University of York
9:01 a.m.
silvercreekvalley wrote:
Sorry if this has been asked before...
I have a few spare TK50 drives, and wondered if
these could be interfaced in some way to a regular
Linux box.
I know the PDP's use a special interface card, but
I seem to recall it was some kind of SCSI variant.
My reason for interfacing is that I have a few
TK50's on PDP 11's and it would be useful to
be able to transfer software.
The TK50 interface is not any variety of SCSI. The TK50Z drive is a
TK50 drive with a TK50<->SCSI bridge board. The TZ30 is a half-high
SCSI version of the TK50. You're probably going to want to look for a
TZ30. In my experience, it's a bit more reliable than a TK50Z.
Peace... Sridhar
9:02 a.m.
On Mon, Apr 21, 2008 at 08:37:08AM -0700, silvercreekvalley wrote:
Sorry if this has been asked before...
It has...
I have a few spare TK50 drives, and wondered if
these could be interfaced in some way to a regular
Linux box.
Do you have bare drives (as one would mount in a BA-23) or
external drives (as one would attached to a MicroVAX 2000)?
I know the PDP's use a special interface card,
but
I seem to recall it was some kind of SCSI variant.
I don't know how the TQK50 might be thought of as a SCSI
variant, unless from a high-level design angle (perhaps).
My reason for interfacing is that I have a few
TK50's on PDP 11's and it would be useful to
be able to transfer software.
If you have a bare drive, I don't know what to suggest
except to find the board from an external drive.
If you already have an external drive, I recall two
variants... the TK50Z-FA and TK50Z-GA. The -FA and -GA
ROMs are different, but the internal drives are identical,
and the interface converter boards are quite similar.
The TK50Z-FA shipped with the MicroVAX 2000, and is nearly,
but not quite, SCSI. I think the largest problem is sharing
the bus with other drives (but it could be more than that).
We had some limited success 20 years ago, hanging a TK50Z-FA
as a lone device off of an Amiga SCSI controller, if I am
remembering correctly.
The TK50Z-GA was *designed* to be a SCSI drive. It has, I
think, a drive unit select switch of some sort, and _should_
play nice on a bus with other drives (can't be sure about
"disconnect" and bus blocking, though).
I have not tried it, but I understand that you can drop -GA
ROMs into an -FA and it will work as a -GA, but I don't
think you can change the drive's SCSI address without some
board hacking.
Another alternative would be to find a TK30Z drive somewhere.
That should be a) more mechanically reliable than a TK50,
and b) ready to go in a SCSI environment.
If you wanted to read/write install tapes and such, a
TK50ish drive on a modern machine could be handy. OTOH,
you might find that a spare serial port and KERMIT might
be easier to work with than hanging an ancient tape drive
on a modern machine, especially since the TK50 holds *at
most* 95MB. With time and wear and tear, etc., even a
9600 bps serial line might seem fast.
Hope this helps clarify some of the details of TK50s.
Good luck with whatever approach you take.
-ethan
--
Ethan Dicks, A-333-S Current South Pole Weather at 21-Apr-2008 at 15:50 Z
South Pole Station
PSC 468 Box 400 Temp -91.8 F (-68.8 C) Windchill -131.1 F (-90.6 C)
APO AP 96598 Wind 9.4 kts Grid 53 Barometer 676.3 mb (10768 ft)
Ethan.Dicks at usap.gov http://penguincentral.com/penguincentral.html
11:30 a.m.
silvercreekvalley wrote:
Sorry if this has been asked before...
I have a few spare TK50 drives, and wondered if
these could be interfaced in some way to a regular
Linux box.
...
My reason for interfacing is that I have a few
TK50's on PDP 11's and it would be useful to
be able to transfer software.
I have a scsi tk50 box; I've used it to make pdp-11 boot tapes by
connecting it to a linux box. It was bit clunky but seemed to work
fine. I used the stock "dd" and "mt" in a shell script.
As I recall this is pretty common (i.e. many others have done the
same)
-brad
Brad Parker
Heeltoe Consulting
+1-781-483-3101
http://www.heeltoe.com
11:39 a.m.
Brad Parker wrote:
silvercreekvalley wrote:
I prefer using a VAX myself, but it should work in Linux without too
much trouble.
Peace... Sridhar
Sorry if this has been asked before...
I have a few spare TK50 drives, and wondered if
these could be interfaced in some way to a regular
Linux box.
...
My reason for interfacing is that I have a few
TK50's on PDP 11's and it would be useful to
be able to transfer software.
I have a scsi tk50 box; I've used it to make pdp-11 boot tapes by
connecting it to a linux box. It was bit clunky but seemed to work
fine. I used the stock "dd" and "mt" in a shell script.
As I recall this is pretty common (i.e. many others have done the
same)
5863
days inactive
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8 comments
8 participants
participants (8)
-
brad＠heeltoe.com -
eric＠brouhaha.com -
ethan.dicks＠usap.gov -
ian_primus＠yahoo.com -
mcguire＠neurotica.com -
pete＠dunnington.plus.com -
ploopster＠gmail.com -
silvercreekvalley＠yahoo.com