Yeah, I used to maintain one of these beasts in the mid-80's.
It is a single 8086, with either 512 or 900-something k ram,
and it runs the Xenix-86 OS. The thing used a couple of Q540
disk drives, and with four users on it, swapped it's brains
out like you wouldn't believe.
The version of Xenix that was running on it at the time
couldn't decide if it was Edition 7 or System III-- fsck
said it was a System III fs, the banner on start up mentioned
something about Edition 7.
Anyways, it's amazing what some careful programming can
accomplish with <1MB ram, and an 8Mc 16 bit CPU. They
ran a cellular billing office with this thing, and they
would load subscriber data onto this thing from 7-track
(or was it 8-track ?) tape that they got from the mainframe.
I had to reload the Xenix OS once-- the default root password
is SOTLA :^).
Jeff
On Sat, 25 Mar 2000 08:09:04 -0700 "Richard Erlacher" <edick(a)idcomm.com>
writes:
> Well, this model 586 has 5-1/4" drives in the main unit and the tape
> drive
> is in a separate enclosure. These are desktop-style boxes, though I
> doubt
> theyd be used on a desktop. The hard drive is a full-height
> nominally 40MB
> 5-1/4" drive. I've left this thing alone, though it's a source of
> Z-80 type
> system parts. The HDC is a 2900-based number not particularly
> similar to
> any other that I can recognize. The tape unit hasn't been opened
> yet. I
> may get to that some day, but I see the two boxes as a source of
> parts and
> little else. They're pretty heavy, so I don't anticipate shipping
> them
> anywhere.
>
> Dick
________________________________________________________________
YOU'RE PAYING TOO MUCH FOR THE INTERNET!
Juno now offers FREE Internet Access!
Try it today - there's no risk! For your FREE software, visit:
http://dl.www.juno.com/get/tagj.
So, would any of our UK members like a VAX 11/750? Possibly one that
has a SCSI adapter?
If so, please get in touch with the fellow who originated the message
shown below. Thanks!
Attachment follows.
-=-=- <snip> -=-=-
On Sat, 25 Mar 2000 12:22:21 -0000, in comp.os.vms you wrote:
>>From: "Jonathan Hunter" <jonathan.hunter(a)stud.umist.ac.uk>
>>Newsgroups: comp.sys.dec,uk.adverts.computer,misc.forsale.computers.other.misc,misc.forsale.computers.other.systems,vmsnet.misc,comp.os.vms
>>Subject: First come first served: VAX 11/750 (UK)
>>Date: Sat, 25 Mar 2000 12:22:21 -0000
>>Organization: Totalserve Internet
>>Lines: 60
>>Message-ID: <8bib4t$ve$1(a)tcnnt0.totalserve.net>
>>NNTP-Posting-Host: jmhpc.ninja.org.uk
>>X-Trace: tcnnt0.totalserve.net 953987037 1006 195.226.56.170 (25 Mar 2000 12:23:57 GMT)
>>X-Complaints-To: abuse(a)totalserve.net
>>NNTP-Posting-Date: 25 Mar 2000 12:23:57 GMT
>>X-Priority: 3
>>X-MSMail-Priority: Normal
>>X-Newsreader: Microsoft Outlook Express 5.00.2919.6700
>>X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700
>>Path: news.uswest.net!news-out.uswest.net!newsfeed.berkeley.edu!freenix!oleane.net!oleane!news-raspail.gip.net!news.gsl.net!gip.net!news.xtml.co.uk!news.totalserve.net!not-for-mail
>>Xref: news-out.uswest.net comp.sys.dec:9583 uk.adverts.computer:75561 misc.forsale.computers.other.misc:8472 misc.forsale.computers.other.systems:3702 vmsnet.misc:227 comp.os.vms:42164
>>
>>Hi,
>>
>>I have a vaguely complete VAX 11/750 system that I would like to get rid of.
>>The notes I have made describing the collection are as follows:
>>
>>Cabinet containing:
>>RA80 - hard disk drive
>>RA60 - disk drive unit - removeable
>>MODEL RA80-CD
>>
>>DECserver 200/MC
>>"Software Product Description" - April 1988, "The
>>DECserver 200 Terminal Server is a network terminal
>>switch for Enternet Local Area networks."
>>Ports - 8 serial ports; Ethernet AUI port.
>>Sticker with Ethernet address (08-00-2B-11-xx-xx)
>>P/N DSRVB-AB
>>C.S. REV B4 ECO C0006
>>MFG. Cloomel
>>------------
>>Model: DSRVB-A
>>
>>RM80. Built differently to rest, i.e. no seperable sides
>>etc.
>>Unit at top of cabinet; start/stop switches etc.
>>Controller unit underneath, slides out. Two massbus
>>sockets - one unconnected; presumably for cable. Other
>>has an empty connector in it. Rack full of cards, and
>>ribbon cable going to drive unit above.
>>MODEL RM80-AD
>>
>>Tape drive
>>MODEL TU81-CA
>>
>>132-column Line Printer
>>MODEL: LP25
>>VARIATION: BA
>>
>>VAX itself (11/750)
>>MODEL SV-BXWAA-AD
>>
>>Plus miscellanous tapes etc.
>>
>>There is also what appears to be a SCSI controller for the VAX, made by
>>SUMMUS Computer Systems. I understand that this is quite a rare item and
>>might be worth something.
>>
>>If anybody has a need for any of the above, I'm based in Manchester and you
>>are welcome to come and collect.
>>
>>If you don't want to make an offer for any of this, then I will allocate it
>>on a "first come, first served" basis. However if you do email me with an
>>offer (monetary, or offers of exchange for other interesting computer goods)
>>then these offers will take precedence over people wanting bits for free.
>>
>>Let me know if any of this is of interest.
>>
>>Jonathan
>>
-=-=-=-=-=-=-=-=-
Bruce Lane, Owner and head honcho,
Blue Feather Technologies -- kyrrin (at) bluefeathertech [dot] com
Web: http://www.bluefeathertech.com
"...No matter how we may wish otherwise, our science can only describe an object,
event, or living thing in our own human terms. It cannot possibly define any of them..."
I have about 120 pounds of Solaris 2.3/4/5 and Oracle 7.0/1/2
documentation for whoever wants to pick it up in Santa Monica. Not
quite classic, I know, but otherwise, they're going in the recycle bin,
with my eight new unsolicited copies of the PacBell Yellow pages.
I have left several Commodore PET 8032's for trade for those
interested.
Regards,
Eliot
.
<Linear/mains frequency supplies normally have internal links (or if
<you're lucky an external switch) to select the voltage. AFAIK, DEC
<always used transformers that were big enough to work at 50Hz (and were
<fine on 60Hz as well, of course).
Th BA23 (and 123) PS is a really wide range unit. For 120 nominal,
the working range is like 85 to 140V and for the 230 nominal it's 180
to 260 or so.
<Ferroresonant supplies (RX01, RX02, some RK02/RK03 systems) are a pain.
<IIRC, there is no way to convert the 60Hz version for 50Hz mains short of
<a new transformer.
Fortunatly they are limited and the PS can be subbed out easily. the
induction motors used are also part of the problem.
<One other thing remains. Most PDP11s have what's called a 'line time
<clock' -- basically an interrupt every mains cycle. This is counted by
<the real time clock program in most OSes, and used to keep real time,
<etc. Of course if you move a machine from 60Hz to 50Hz power or vice
<versa, the real time clock will run slow/fast until you re-SYSGEN the OS
<for the appropriate frequency. This is not a big problem -- things still
<work -- though.
If your really bugged by it you can supply your own LTC derived from
other sources.
<So in your case. The PSU will be fine if you flip the switch. The machine
<should work (everything inside the box runs off the DC outputs of the PSU
<and doesn't care about frequency). The real time clock may run slow.
Also depends on the CPU board used as some use the TOY clock for LTC.
This does not include the 11/03, 11/23 series. The 11/73 series I can
only speak on the KDJ-11A I have and that uses a traditional LTC like the
11/23. Later ones may differ.
I cheat and synclock a 300hz osc to most submultiples 50/60hz then divide
by 5 to get 60hz. Trivial circuit, predictable result. Or take a crystal
and divide to 60hz (or 50 if thats what you need).
Allison
>One other thing remains. Most PDP11s have what's called a 'line time
>clock' -- basically an interrupt every mains cycle. This is counted by
>the real time clock program in most OSes, and used to keep real time,
>etc. Of course if you move a machine from 60Hz to 50Hz power or vice
>versa, the real time clock will run slow/fast until you re-SYSGEN the OS
>for the appropriate frequency.
On many of the operating systems, you don't have to do a SYSGEN - just
tweak a number in the configuration word and viola, it's now a 50Hz machine.
For an RT-11 machine, in particular, you can tweak this on a running
system if you wish:
.type 50hz.mac
.MCALL .PVAL, .EXIT
; RMON Fixed offsets
CONFIG = 300 ;Configuration word 1
CLK50$ = 000040 ;50-cycle system clock
HZ50: .PVAL #AREA,#CONFIG,#CLK50$,BIS ;Get configuration word
.EXIT
AREA: .BLKW 4
.END HZ50
.macro 50hz
.link 50hz
.show conf
RT-11FB V05.07
Booted from DU1:RT11FB
USR is set SWAP
EXIT is set SWAP
KMON is set NOIND
MODE is set NOSJ
TT is set NOQUIET
ERROR is set ERROR
SL is set OFF
EDIT is set KED
FORTRAN is set FORTRA
KMON nesting depth is 3
CLI is set DCL, CCL, UCL, NO UCF
PDP 11/84 Processor
2048KB of memory
Floating Point Microcode
Extended Instruction Set (EIS)
Memory Management Unit
ECC Memory
Cache Memory
PMI Memory
60 Hertz System Clock
FPU support
.run 50hz
.show conf
RT-11FB V05.07
Booted from DU1:RT11FB
USR is set SWAP
EXIT is set SWAP
KMON is set NOIND
MODE is set NOSJ
TT is set NOQUIET
ERROR is set ERROR
SL is set OFF
EDIT is set KED
FORTRAN is set FORTRA
KMON nesting depth is 3
CLI is set DCL, CCL, UCL, NO UCF
PDP 11/84 Processor
2048KB of memory
Floating Point Microcode
Extended Instruction Set (EIS)
Memory Management Unit
ECC Memory
Cache Memory
PMI Memory
50 Hertz System Clock
FPU support
--
Tim Shoppa Email: shoppa(a)trailing-edge.com
Trailing Edge Technology WWW: http://www.trailing-edge.com/
7328 Bradley Blvd Voice: 301-767-5917
Bethesda, MD, USA 20817 Fax: 301-767-5927
>One other thing remains. Most PDP11s have what's called a 'line time
>clock' -- basically an interrupt every mains cycle. This is counted by
>the real time clock program in most OSes, and used to keep real time,
>etc. Of course if you move a machine from 60Hz to 50Hz power or vice
>versa, the real time clock will run slow/fast until you re-SYSGEN the OS
>for the appropriate frequency. This is not a big problem -- things still
>work -- though.
Actually, the KDJ11-B based machines allowed any of the following
settings for the LTC interrupt rate:
1) Line time clock (tied to power supply)
2) 50 Hz
3) 60 Hz
4) 800 Hz
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry!zk3.dec.com |
| Unix Support Engineering Group | (home): mbg!world.std.com |
| Compaq Computer Corporation | addresses need '@' in place of '!' |
| 110 Spitbrook Rd. ZK03-2/T43 | URL: http://world.std.com/~mbg/ |
| Nashua, NH 03062 | "pdp-11 programmer - some assembler |
| (603) 884 1055 | required." - mbg |
+--------------------------------+-------------------------------------+
I forgot to add that the sticker says it is set for 110v and 60hz.
We have 50hz. Perhaps it is necessary to change something on that score.
-----Original Message-----
From: Olminkhof <jolminkh(a)nsw.bigpond.net.au>
To: classiccmp(a)classiccmp.org <classiccmp(a)classiccmp.org>
Date: Saturday, 25 March 2000 21:54
Subject: BA23 Power Supply
>With all this talk of PDP11/23's I am looking at my BA23 with I think an
>11/73 CPU inside it.
>
>I haven't powered it up because it is set for 110v and we have 230v here.
>There's a switch on the back but a big sticker on the PS itself says to
>refer to the operating manual . . . sort of like there must be other things
>to do also.
>
>Does anyone here know about these things?
>
>Thanks,
>Hans
>
>
<I forgot to add that the sticker says it is set for 110v and 60hz.
<We have 50hz. Perhaps it is necessary to change something on that s<
That may impact the line time clock (time keeping) but not the PS as it's
a switcher.
Allison
<I haven't powered it up because it is set for 110v and we have 230v here.
<There's a switch on the back but a big sticker on the PS itself says to
<refer to the operating manual . . . sort of like there must be other thing
<to do also.
Well that switch has two positions... yours is in the wrong one for the
home town. The BA23s I've seen all had the "international" power supply.
The "see manual" reference is DEC prtoecting themselves. I presume it's
the standard Astec H7864A.
Allison
<restorable backup of the drive. The two floppies respond to DIR/Bad, and
<Init/Bad as devices DU1 and DU2:. But I get 'bad sector in system area'
<when I try to init. How do I low-level floppies?
Get a DEC Rainbow is teh common answer. There is no LLF utility with RT11
for RX50 (that dual drive).
Allison
