How does one park the heads on an MFM hard drive when there's no park
command available? I don't suppose the answer is to either create one or
copy one to the hard drive? :)
--
Sellam Ismail Vintage Computer Festival
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> Sheesh,
> I've been offered a Burroughs L7000, but I don't even know
> what it is. Any hints?
>
> http://members.cox.net/stengel/temp/L7000.jpg
>
> Steve.
Well, it looks like an A/C unit in a hotel ;-)
>So I imagine any device drive with the X at the end is the better one to
>use with the XM monitor? Or is it mandatory to use X device drivers in
>the XM monitor?
It is mandatory... the system knows to append an X to any two-character
device name
>So this brings up another question: I've noticed that I don't explicitly
>need to LOAD device drivers for the devices I want to use when I boot
>RT-11. In particular, I don't need to LOAD DD when I want to use the
>TU58 simulator. Are they found and loaded automatically when the OS
>boots, or...?
Most utilities and user applications know to .FETCH device drivers they
need in order to do their task. After they are done, the drivers are
.RELEAsed. If they are LOADed before the program is executed, a .FETCH
and .RELEA are no-ops.
If they aren't loaded and aren't .FETCHed, then they simply are not in
memory.
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL,ST| email: mbg at world.std.com |
| Member of Technical Staff | megan at savaje.com |
| SavaJe Technologies, Inc. | (s/ at /@/) |
| 100 Apollo Drive | URL: http://world.std.com/~mbg/ |
| Chelmsford, MA 01824 | "pdp-11 programmer - some assembler |
| (978) 256 6521 (DEC '77-'98) | required." - mbg KB1FCA |
+--------------------------------+-------------------------------------+
(this is one of the messages that *didn't* show up)
OK, next load of questions.
I've been trying to create a "virgin" system from the install media I
have. I have so far successfully sysgenned and built RT11 v5.0, and
installed it on an RL02. Great.
However, the version that boots off one of the hard disks built into the
PDP allows me to access four partitions in total - DU0: to DU3: - but my
own version only has DU0: (same as normal) and DU1: (same as DU3: in the
version of RT11 installed on the hard disk).
If I say "SET DU2: disk=0, part=1" then I can see my "old" DU1: as DU2:,
and so on.
What do I need to change to get it to come up like this? It doesn't
appear to be a load of "SET" commands in the STARTS.COM file.
Gordon.
>> Once done, the SET command values are held in the
>> DU.SYS device driver file. You do NOT need to
>> do the SET commands each time. Probably not
>> recommended in any case.
>Ahaaa... Is that saved in DU.SYS when you issue the commands, then? Makes
>sense. I'll try it when I get home.
SET commands only operate on, and change, in on-disk copy of the
handler file. If you are booted from a given device and you issue
SET commands for that device handler, they won't take affect
until you reboot..
Same thing for issuing SET commands for device handlers which
are LOADed. But at least for them you can UNLOAD and LOAD
them.
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL,ST| email: mbg at world.std.com |
| Member of Technical Staff | megan at savaje.com |
| SavaJe Technologies, Inc. | (s/ at /@/) |
| 100 Apollo Drive | URL: http://world.std.com/~mbg/ |
| Chelmsford, MA 01824 | "pdp-11 programmer - some assembler |
| (978) 256 6521 (DEC '77-'98) | required." - mbg KB1FCA |
+--------------------------------+-------------------------------------+
Sheesh,
I've been offered a Burroughs L7000, but I don't even
know what it is. Any hints?
http://members.cox.net/stengel/temp/L7000.jpg
Steve.
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Does anyone have a pinout for the Signetics 82S83 BCD full-adder chip (16
pin DIL package)? A google search didn't turn up anything useful that I
could see.
All I can find is a comment in the 74F583 data sheet (which I have) that
said chip is functionally identical to the 82S83. But that doesn't
necessarily mean the same pinout (although, of course, telling me that
those 2 chips are the same pinout would be enough to let me get on).
FWIW, this chip is used in the high-speed language processor option for
the HP9845 (which is what I am currently working on), so it's on-topic here.
-tony
woodelf wrote:
>The main problem I see with the current
>crop of PDP-8 >clones/replica's today is
>lack of paper tape and other hardware
>at the time -- non volatile memory.
Actually, it's possible to build a reader fairly
easily. I liberated read mechanisms from Remex
"Director" readers I picked up cheap on eBay, and
built a microcontroller stepper controller/serializer
(which was fairly trivial-the power to the stepper is
done with 0-brainer power FETs; it was not difficult
to reverse engineer the connections to the head). The
smallest one I built is not much bigger than the read
mechanism itself, and runs on an old laptop power
supply. It will do only about 60 CPS mostly due to
power limitations, but how fast can you handle tape (I
have reeled units that I built serializers for also).
All of the readers and mechs that I have are
industrial strength, and I beleive that in home use
the mechanisms will last essentially forever
(certainly longer than I will). Older Remex's used
now-unobtainable lightbulbs, which I have replaced as
needed with high-power LEDs (the "Intel" readers used
Remex mechanisms).
The oldest reader I have is an Oktronics (NIB) which
had a very special (and broken) lightbulb. The #$@$#@
lightbulb cost $42-I couldn't bear hacking LED's into
it.
It is possible to build a "slot" type reader with
LED's and photodiodes; I built one but abandoned it
when I built the mechanized units because they are
"neater".
The real problem in a paper tape "ecosystem" is in the
punches, "handling equipment" and the tape itself; I
got lucky and got a lot of Mylar cheap some time ago,
as well as some real DEC fanfold and reel tape. Mylar
tape is now fabulously expensive at retail.
The older DSI punches are very rebuildable; I got a
very beat-up one in, replaced the belts (standard) and
the caps in the power supply, made a replacement chad
box from a $2.00 radio shack project box and some
Velcro and it works great. If the electronics fails (I
think that they use an F8 microprocessor) I'll just
replace it with work-alike modern electronics.
I have a FACIT reader that was severely damaged in
shipping, but it has a good punch head. I intend to
make a smaller case for it and run it with a
microcontroller and FETs; I think I can reduce the
power requirements by only punching one hole at a time
(obviously, it will be slower, but who cares). Most of
the size/weight in the thing is in the colossal linear
power supply. Again, this mechanism in home use could
last a very long time.
Paper tape is a PITA and fun at the same time. I like
to point out to friends that the data on the
metallized Mylar tape will be readable (even
visually!) and usable long, long after their hard
disks are very deep down in landfills!
-Steve Loboyko
Website: http://juliepalooza.8m.com/sl
Nixie Watch (one-tube):http://juliepalooza.8m.com/sl/complwatch.htm
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>From DEC's price list 1997:
-THZ02-AA 6GBF Cipher tape drive sgl en
-THZ02-AB 6GBF Cipher tape drive differ
-THZ02-AC THZ02-AA in tabletop enclosur
-THZ02-AD THZ02-AB in tabletop enclosur
-THZ02-AE 6GB Cipher tape drive interna
-THZ02-AF 6GB Cipher tape drive differe
-THZ02-AG THZ02-AE in tabletop enclosur
-THZ02-AH THZ02-AF in tabletop enclosur
-THZ02-BA 6GB TT tape dr,SCSI OEM USD
-THZ02-BC 6GB emb tape dr,SCSI OEM
Phil St.Sauveur
Desktop Integration Inc.
-----Original Message-----
From: cctech-bounces at classiccmp.org
[mailto:cctech-bounces at classiccmp.org]On Behalf Of Bruce Lane
Sent: Sunday, March 13, 2005 11:32 AM
To: cctech at classiccmp.org
Subject: DEC THZ02: Wottizzit?
Hi, gang,
I've come across a DEC THZ02 external/stand-alone tape drive in a nice enclosure with what is labeled as a SCSI interface. It resembles DLT in terms of its cartridge style, but it doesn't look like any "normal" DLT drive I've come across before in that it has no manual density selection that I can find.
Details? Also, if anyone wants it (I certainly don't need it), I would be happy to send it along for the stunning total of $10 plus shipping.
Let me know... Thanks much.
-=-=-=-=-=-=-=-=-=-=-=-
Bruce Lane, Owner & Head Hardware Heavy,
Blue Feather Technologies -- http://www.bluefeathertech.com
kyrrin (at) bluefeathertech do/t c=o=m
"If Salvador Dali had owned a computer, would it have been equipped with surreal ports?"
