one thing we have fine from the 5000 stuff are all these beautiful
cord wood logic things all gold and pretty but most of these got
scrapped for gold along the way.. I do not know what other units used
in but some folks mentioned 5000
I have schematics for some of these too.
ed# www,smecc.org
In a message dated 9/4/2015 11:23:16 P.M. Mountain Standard Time,
nw at retroComputingTasmania.com writes:
We would be glad to hear from anyone who might have new material
related to the Burroughs B6700.
We're on the hunt for any manuals or software related to the Burroughs
large systems so we can build an emulator for the B6700. This search
includes the B5000, B6000, B7000 families, since there is considerable
overlap across these families and collateral from one system family
can assist understanding another. Example models include B5500, B5700,
B6500, B7500, B6700, B7700, B6800, and B7800.
We were amazingly lucky with the B5500 to have so much of the critical
documentation (thanks Bitsavers!) and a complete suite of system
software, but even though the B6700 was more recent and produced in
larger numbers we're not having the same level of good fortune finding
artifacts.
What we have so far is documented here:
https://docs.google.com/spreadsheets/d/1JnMsyE8ssJi_-MUsK0rT9LPtNpeJCpTv1QrF
w-917Y8/edit?usp=sharing
If you're interested in this system then you likely remember that it
had a particularly impressive front-panel display, seen here:
http://www.retrocomputingtasmania.com/home/projects/burroughs-b6700-mainfram
e#TOC-B6700-Display-Panel
This was known as the MDL display: Maintenance Diagnostics Logic
display. Because the MDL had the 4 x top-of-stack registers down to
the bit-level particular bit-patterns allowed words to be displayed.
The early MCPs put IDLE into the display during IO waits, and
subsequent releases: B for Burroughs, but sites quickly started
putting their own company initials or the time.
The Danish museum is so far the only place I've found that kept the MDL:
http://datamuseum.dk/wiki/Genstand:11000045_Konsolpanel_Burroughs_B6700
Thanks to Finn Verner Nielsen for being so helpful and undertaking an
expedition into their warehouse to locate and photograph the item for
us. On that DDHF web-page you will see on the left of the picture the
B7800 MDL they have too.
My goal is to also construct a replica of the B6700 MDL.
Steps undertaken so far:
Posts to newsgroups
Posts on LinkedIn, wikipedia, Yahoo groups
Emails to a few dozen people who were involved with the system
Trawling the Internet
I will have to see. When we acquired the Aldrige collection at SMECC we
pulled off all the really really early material and put the remainder
in storage which should have some of this... we also have the unisys
crossover stuff and when why bought up the Varian minicomputer too. I
remember we boxed and boxed... and deep stored it. guess it did not seem
"really old" at the time....but it has been about 10 years since we have
pulled it out and run our hand through it.
Background on Aldrige started on the electrodata Pasadena ... ended up
running the phx field service effort here and was a great packrat.
The effort to get to this material is a lot of work
ed sharpe _www.smecc.org_ (http://www.smecc.org)
In a message dated 9/4/2015 11:23:16 P.M. Mountain Standard Time,
nw at retroComputingTasmania.com writes:
We would be glad to hear from anyone who might have new material
related to the Burroughs B6700.
We're on the hunt for any manuals or software related to the Burroughs
large systems so we can build an emulator for the B6700. This search
includes the B5000, B6000, B7000 families, since there is considerable
overlap across these families and collateral from one system family
can assist understanding another. Example models include B5500, B5700,
B6500, B7500, B6700, B7700, B6800, and B7800.
We were amazingly lucky with the B5500 to have so much of the critical
documentation (thanks Bitsavers!) and a complete suite of system
software, but even though the B6700 was more recent and produced in
larger numbers we're not having the same level of good fortune finding
artifacts.
What we have so far is documented here:
https://docs.google.com/spreadsheets/d/1JnMsyE8ssJi_-MUsK0rT9LPtNpeJCpTv1QrF
w-917Y8/edit?usp=sharing
If you're interested in this system then you likely remember that it
had a particularly impressive front-panel display, seen here:
http://www.retrocomputingtasmania.com/home/projects/burroughs-b6700-mainfram
e#TOC-B6700-Display-Panel
This was known as the MDL display: Maintenance Diagnostics Logic
display. Because the MDL had the 4 x top-of-stack registers down to
the bit-level particular bit-patterns allowed words to be displayed.
The early MCPs put IDLE into the display during IO waits, and
subsequent releases: B for Burroughs, but sites quickly started
putting their own company initials or the time.
The Danish museum is so far the only place I've found that kept the MDL:
http://datamuseum.dk/wiki/Genstand:11000045_Konsolpanel_Burroughs_B6700
Thanks to Finn Verner Nielsen for being so helpful and undertaking an
expedition into their warehouse to locate and photograph the item for
us. On that DDHF web-page you will see on the left of the picture the
B7800 MDL they have too.
My goal is to also construct a replica of the B6700 MDL.
Steps undertaken so far:
Posts to newsgroups
Posts on LinkedIn, wikipedia, Yahoo groups
Emails to a few dozen people who were involved with the system
Trawling the Internet
I reconnected the data bus pins, and disconnected all the MA0..11 pins (in
case it's DMAing into memory when it should not be). Nope, same issue. Won't
boot Serial Disk, corrupts the upper six bits of the loader.
Only bus left is the memory data MD0..11, but that can't be shorted because
on the card it has only inputs. Also the IOT address is decoded from it and
those select properly. Still thinking it's DMA, will try watching the break
request and other DMA lines for activity.
Nothing unexpected there.
But at last I found something... I think. Despite it not making sense, I
disconnected the top 8 bits of MD0..7 (thus not only disconnecting the bus
receivers on the card, but also completely deselecting it). Now the system
booted and runs normally with the card plugged in! So, I figured either one
of the 8640 receivers at E3, E20 (page 5 of the 10-page schematic) is leaky,
quite possibly E20 which handles bits 4-7 the "troublemakers" from before,
or the 8136 at E11 which appears to be just a multi-input AND/OR gate combo
to select IOT x60x/x61x and was working with scope loop.
I gradually reconnected lines until it started failing to boot and wiping
out the loader again... I am so tired of toggling that loader in! At least
it's only 26 (octal) words.
Turns out MD4 was being pulled down weakly (to a volt or two) by something
when it should have been pulled up. Wiggling and flexing the card caused it
to work, intermittently. But I could not find it even with close visual
inspection. I suspected a tiny tin whisker somewhere...
So I crossed my fingers and tapped the pin with a cliplead from the 25 amp
+5 volt supply. Figured I had nothing to lose at this point! ... and
apparently did clear the short :)
Now that line looked normal just like the other 11 memory data bus lines.
OS/8 restarted with no problem, too.
Started the diagnostic AJRLAC (the "Diskless Controller Test"). Immediately
indicated a hard failure on bit 10! Oh $@#%. Now what did I do...
But it just took a minute to pull the extender card and sure enough I had
just made a bad solder joint reconnecting that pin and it had come apart
with the flexing ;)
Fixed that... running four passes without an error so far. Dare I touch the
middle of the board again?
Yep... flexing in both directions, no failures!
I think I got it! Make that eight complete passes with the extender removed
and the board in the cage.
Running AJRLIA on a scratch pack now. Initally I got a very occasional
seek/tracking error (Command Reg B 1017 or 1117) once per pass on each
drive, but it's lessening with "exercise"...
It's 90F in the computer room too, which may be above spec for an RL02
anyhow. Just finished Pass 0002 on Drive 1 without errors :)
-Charles
Dear sirs...
Ok, life does nasty things to us, and seems it is my time. Due to personal
and health problems, I'll have to sell some of my collection. As bad as it
is, I can't really afford keeping much of my stuff. I'll save just the nice
gifts I got from friends and my beloved //e "Woz edition".
So, there are some computers that may be of interest to you
- Milmar Laser IIc apple clone - Clone of the Apple //c, but it isn't a //e
- it is a ][c in a case of a //c. Has power supply, original manual and
external slot expansion. $800 o.b.o.
- Prologica Sistema 600 - Clone of the Intertec SuperBrain
- Prologica CP500 - Clone of the TRS-80 model III
- Prologica CP400 (boxed) - Clone of TRS-Color model 1, in the box of a
Timex Sinclair 2068(!)
- Prologica CP300 - Clone of TRS-80 model III, but way portable
- Prologica CP200 - Clone of Sinclair ZX-81
- Microdigital TK95 (boxed) - Clone of Sinclair ZX-Spectrum, but in a
Commodore Plus/4 box (!)
I'll have more interesting things, as soon as I have more time to dig the
pile
Shipping from Sao Paulo, Brazil.
Thanks,
Alexandre
Saw this in AFC
Another water damaged collection heading to the landfill
--
Subject: Houston (and everywhere else), we have ... an opportunity
From: hlctminfo at gmail.com
Injection-Date: Thu, 03 Sep 2015 15:37:06 +0000
My name is John Keys, and I incorporated the Houston Computer Museum in May=
2003 as 501(c)(3) non-profit.
I've been good at collecting things. I've have various PDPs, an HP3000, SE=
L 810A, SDS 910, and a Cray YMP/EL8. I have an IBM 083 card sorter and sev=
eral keypunchs (models 024, 026, 029 and 129). I have over 1,200 books and=
manuals. And those are just a small sample.
That's the good news.
The bad news is that it's all in storage, in my home, or in a 3,300 square-=
foot warehouse. I don't have exhibit space. You might have heard that it =
rains in Houston; the warehouse has flood damage that needs to be mitigate=
d.
I haven't been good at getting the 21st century to work for me, and this is=
where you come in. I need a functional web page, one that makes it easier=
for people to donate online. I need a contact email link that works.
If you can help me get this done, I'd be grateful.
What's at stake? I'm 70 years old, and if I can't make a go of this, all t=
hat equipment will get recycled or hauled off for scrap or dumped in a land=
fill. And all of that documentation will go with it.
If you can help me with web hosting and web page design, let me know. Advi=
ce is nice -- I've had lots of it -- but what I really need is people who c=
an step up and do what I haven't done. I need help in cleaning all these ar=
tifacts that were damaged by the flood. Contact me by email discuss how you=
can help.
If there are enough people out there who care about this stuff, we can do t=
his. You don't have to live in Houston. You don't have to live on the Gul=
f Coast. It's even OK if you don't live in Texas.
To donate online, go to http://www.hlctm.org/services.htm and click on "Don=
ate."
To contact me, send email to hcmjkeys at yahoo dot com.
Once we have something presentable, come visit. And thanks very much for r=
eading this.
John Keys
I still can't get my RL8A (M8433 RL01/02 disk controller card) working again
in my 8/A system. It won't boot from the RL02 any more.
In my backplane I found it to be mechanically sensitive (AJRLAC diskless
controller test would show errors always involving bits 4-7 being
unexpectedly 0's), and when the card was flexed gently the errors would
increase dramatically during the test. No visible bad/missing solder joints
or broken traces.
Recently I sent the card to a list member who tried it in his system. He
could boot OS/8, but when attempting to open a file with EDIT the system
would crash. This behavior was repeatable and did not occur with his
controller.
I now have SerialDisk running via Omni-USB, emulating two RK05 drives from
my laptop, booting OS/8. This works perfectly - until I put the RL8A in the
backplane!
Then the system won't boot and also corrupts the first part of the boot
loader that resides at 0020-0045.
However, only the first 7 instructions at 0020-0027 are mangled, and all
seven words have their most significant six bits set to 0 (for example, 7240
becomes 0040).
The selects to the various 8234's (open-collector drivers to the data bus)
are working properly in a scope loop. Figured I was on the right track with
a bad 8234.
I physically disconnected the middle 4 bits of the DATA0..11 bus (at the
extender card rather than hack up the board)... system still won't boot,
still corrupting locations as described.
Next, I disconnected the entire data bus, all 12 bits, same problem! So
whatever is the trouble it's NOT an 8234 pulling on some of DATA0..11 as I
thought!
I am starting to think there is a defect with the DMA (aka Data Break)
facility on either this card OR even the CPU itself... everything else in
the system is programmed I/O, not DMA.
Obviously something is pulling down the memory-data bus when it shouldn't
be, and writing zeroes over the upper six bits of some words, but on this
controller card there are only inputs from the memory data bus MD0..11. It
has its own memory address registers for DMA which drive the MA0..11 lines.
I checked the various signals coming out of the card and (at least
statically) none of them are in the "wrong" state...
Any thoughts on testing the DMA facility?
thanks
Charles
the SMECC museum is a canadate if our onmnibus 8 still runs. have
not powered it up in 20 years.
In a message dated 9/4/2015 1:37:34 A.M. US Mountain Standard Time,
spacewar at gmail.com writes:
A building next door to one of my offices was a datacenter/colo facility. It
has sat vacant for quite a few years, and the new owner contacted me
yesterday about some unrelated items. I asked about the raised floor and she
said "all available, dirt cheap, come over and look".
Sometime next week I will go take a look, but I know folks here have
occasionally expressed interest in getting a section of raised floor for
their "machine room". If there's interest, let me know.
Best,
J
Hi folks,
as you might remember I made about 20 OmniUSB Omnibus to USB adapters. Since a
few month they're all sold.
The last days I got some inquiries for more. So I think of making a new batch.
As my board supplier has doubled (It was so cheap before..!) the price for gold
plated contact PCBs, the board will be more expensive in the end. And I
massively underestimated the labour...
And I'll overhaul the design.
The original board description:
http://pdp8.hachti.de/projects/omni_usb/
The facts about a new board:
- Exactly same functionality
- Smaller
- Still gold plated contacts
- Still KL8E compatible
- Power supply parts will be moved away from the PCB's edge
- USB connector will be moved away from the PCB's edge
The board will cost (fully assembled and tested) EUR 105 (without VAT for
overseas buyers) and About EUR with VAT for anyone in the EU.
A still to design cusom handle (I think of laser cut acrylic with wood) to make
the board the original size will be available in the EUR 25 range.
If YOU are interested, please let me know. I'll make my decision with regards to
the feedback I'll get from this posting.
I need at least 10 seriously interested people to make it happen again.
Kind regards
Philipp
