My new build, and what it can do.

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Guido De Grefte

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Apr 15, 2021, 5:26:19 PM4/15/21
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It is dark outside when I first turn on the lights. Silently the black panel stares back at me. Just before doubt creeps in, the first red dots signal life, progress, hope. Solidly soldered, 64 blinking leds proudly next to the arrogant 5120 x 2880 retina screen where this text is displayed. Small, in this humble plum color next to her shining and shouting 27 inch neighbour.  “But what can it do?”, people ask. “It can’t do much, but it has done a lot.” would be the proper response. “It has changed the world”. Looking at these blinking lights is like looking at the birth of a star. Don’t look at what it is, look at what it can become. Yes, we see progress. But above all, we see promise.

The background of my VNC-desktop is a picture of a woman in front of a PDP-11. She looks like my mother when I was 11 years old, in a jumpsuit and Brigitte Bardot hair. She holds a card, probably the programming card for her ‘family of PDP-11 computers’, the same one as I am holding now. And I guess she is keying in the bootloader of the program that would run, evolve and grow into the digital life as we know it. I manually toggle in a bootloader on the PiDP-11. Then my daughter looks over my shoulder and asks: “What are you doing?”. I answer: “This is a time machine. This was once a machine that brought us the future and now this little box can send me back to when I was your age.”

Then I search the PiDP11-forum for the key switch. I want to make sure that I don’t misunderstand the purpose of this key, which is in my build is actually doing, well, nothing. It is reassuring to find that this is indeed the first key I’ve ever owned that I don’t need to worry about loosing. It is proof of the proud name that Oscar has chosen for his company. Further browsing the forum for other facts and feedback that I could perfectly live without, I notice something unusual. People are nice. They are not in a hurry. There is no judgement. They find time to build a kit with their children and enjoy every little 8th bit of it, including the bubbly plastic. On this forum the people take the time to write whole words to express emoticons, and to make mild jokes without brute force. So when people ask: “But what can this thing do?”, the answer could be: “It is a miracle machine, it brings out the best in people!”

A big thank you for everybody who made this possible, specially for Oscar who has made this wonderfull kit and my wonderfull wife who bought this for my birthday.

Bill Saltzstein

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Apr 15, 2021, 6:56:03 PM4/15/21
to Guido De Grefte, [PiDP-11]
Dear Guido,
  I loved your note, thank you.  You’ve also crystalized why I have these various machines blinking lights on my shelf that I play with, and I will credit you with the perfect notion going forward.  I’m going to make a small sign with your words: "“This is a time machine. This was once a machine that brought us the future and now this little box can send me back to when I was your age.””

  I had just finished explaining to a young colleague why I use an 8 character email name on email systems when I can, which was of course received with blank looks at my grey hair.  Time machine indeed!

Thank you,
Bill
— — 
Bill Saltzstein



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Geert Rolf

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Apr 16, 2021, 9:42:50 AM4/16/21
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What could this thing do fourty years ago?

Just some real examples:  create newspapers every day (Utrechts Nieuwsblad, Dagblad van het Noorden, De Gelderlander (?)). Those systems ran RSX-11D for reasons of type-ahead capabilities. Hospital administration (Leiden and some other academic hospitals). Running B.O.S. developped by group around Prof. Bakker at Leiden University. Later: BAZIS Operating System. Should we port that operating system to the PiDP-11?  It's an operating system integrated with a database (like MUMPS is; same branch) and served a very large amount of users. BOS also used at the dutch central Royal Library (KB) in The Hague. They ordered expansion of diskspace every month: CDC 9766 (300MB) diskdrive. Financial administration of the faculty of science at Nijmegen Univeristy ran on a PDP 11/70 with 512KB memory, an RP04 (88MB) disk and with remote diag frontpanel. The High Energy Physics group in Nijmegen had an 11/70... they travelled up and down to CERN with magtapes in the boot of a car. (Swiss connection, Oscar!)

Obviously there are dozens of applications for a PDP 11/70. I just mentioned examples I do remember. We should keep in mind 11/70s (released in 1975) were quite expensive. At considerable lower cost the 11/44 (sorry no blinkenlights) got very popular (1979).

Geert


John Anderson

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Apr 16, 2021, 10:13:04 AM4/16/21
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Thanks for the inspiring words!!

Johnny Billquist

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Apr 16, 2021, 4:12:04 PM4/16/21
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If we just reminiscence about where PDP-11s been around, I can tell of a
lot.

When I went to school, we had one PDP-11/70 which was shared between
four gymnasiums in Stockholm, Sweden (running RSTS/E). We had classes
teaching programming, and of course people played games, developed
software, used chatting software, mail, and god knows what else to
communicate and have fun.

Lots of saw mills in Sweden used/use PDP-11s to control the sawing of
wood. (There were some concerns around Y2K, but in the end it was a
non-issue.)

Lots used for steel mills to control all kind of processes. There are
probably some still in use.

Volvo and Saab both used PDP-11s in test equipment. There is a fair
chance some are still in use. I certainly know plenty were still in use
10 years ago in engine test rigs.

I know that for communication and tracking of buses in one city were
still using PDP-11s a few months ago. They switched to emulated 11s more
than 10 years ago, though. They might be phasing them out now, though.
(The main person handling things just retired.)

PDP-11s were used to control mass spectrometers. I have the software
around, but not the hardware. :-)

And that is just some of the things where I have been around the
systems, or even been involved in developing them.

I've heard of way more...

Johnny
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Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: b...@softjar.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol

Bill Saltzstein

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Apr 16, 2021, 4:16:53 PM4/16/21
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Louis Smith

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Apr 16, 2021, 4:19:24 PM4/16/21
to Johnny Billquist, [PiDP-11]
Ours was used for the US version of Prestel - named Viewdata at the time. developed by SDL over in Camberly, IIRC.  Written in ForTran, and use the commercial version of the old ISC "Compucolor 8000" terminals.  Had a blast with that software, and the original Adventure game.  Even got a copy of the Wirth Pascal 2-phase compiler/runner.  

A hell of a lot of fun way back when I was a young computer jockey!

Louis



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Johnny Billquist

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Apr 16, 2021, 4:22:45 PM4/16/21
to Louis Smith, [PiDP-11]
Oh. And just on the (slightly) silly side.

I am, of course, hosting all RSX manuals, as well as RSX software
distribution, and some generic web pages on a PDP-11 running RSX today.
So there are obviously a lot a PDP-11 can be used for, even now.

( See http://mim.update.uu.se/ )

Johnny
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> Johnny Billquist                  || "I'm on a bus
>                                    ||  on a psychedelic trip
> email: b...@softjar.se <mailto:b...@softjar.se>             ||
> Reading murder books
> pdp is alive!                     ||  tryin' to stay hip" - B. Idol
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Warren Hardy

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Apr 16, 2021, 8:34:22 PM4/16/21
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In the late 1988-1990 I did an internship, I worked on a PDP 11/73 running RT-11. We developed an automated artificial rolling road (aka Dynamometer). These were installed in Landrover/rover, Nissan, Volkswagen research lab, and ford, across Europe, mainly in research and engineering test labs. The system ran on a PDP-11/23 using assembly and Micropower Pascal. 

Great days.

A prior small internship in 1987, I worked on a batch processing system also based on an PDP-11, don’t know which one, it was running Unix, this system was with ICI Pharmacies, now called astra Zeneca. Head office and main research lab was on a campus just outside my hometown.

Mike Kostersitz

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Apr 17, 2021, 12:25:35 AM4/17/21
to [PiDP-11], Warren Hardy
First piece of software I worked on was the backend for the in vehicle data radio system used by the city of Vienna to coordinate emergency vehicles i.e. Where the patient was and which hospital to take them to.
Ran on an 11/70 with a serial to radio interface and it served over 800 emergency vehicles at the time


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Subject: Re: [PiDP-11] My new build, and what it can do.
 
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Michael Katzmann

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Apr 17, 2021, 10:28:53 AM4/17/21
to Louis Smith, Johnny Billquist, [PiDP-11]
In the early 1980's I worked on an 11/34 running RT11 that generated Teletext for ATN Channel 7 in Sydney. (called Ceefax & Oracle in the UK ..  data in the blanking interval of the television signal). What I remember is that it was continually thrashing RK05 disks to serve the pages. I'm sure they were not designed to be used like that! 

Johnny Billquist

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Apr 17, 2021, 12:16:52 PM4/17/21
to Michael Katzmann, Louis Smith, [PiDP-11]
Disks are designed to be used...

The 11/70 I mentioned at my Gymnasium had 2MB of memory, and one RM03 disk.

On a common day you had about 40 users active. Limit in RSTS/E is 63,
and some days we came close to that.

60 users, each maybe using 32K already comes close to 2MB of memory in
itself. And of course you also had the system requiring some memory. So
in essence when it hit those number of users, the system was constantly
swapping. So I can imagine the RM03 constantly in action. And that was
fine. But the system became pretty slow with that number of users online.

But disks really had to consider that this could be very normal.

Johnny
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> --
> Johnny Billquist                  || "I'm on a bus
>                                    ||  on a psychedelic trip
> email: b...@softjar.se <mailto:b...@softjar.se>             ||
> Reading murder books
> pdp is alive!                     ||  tryin' to stay hip" - B. Idol
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emt377

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Apr 17, 2021, 12:36:26 PM4/17/21
to [PiDP-11]
A member of the IAS (PDP-11 OS, based on RSX-11D with timesharing additions) development team once told me that they had an IAS system "counting the cars on the New Jersey Turnpike".  I had no reason to doubt him.

(I assume in a retrocomputing forum I don't need to explain the reference. We're all old, right?)

Mark Matlock

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Apr 17, 2021, 3:20:37 PM4/17/21
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Adding to the stories of what PDP-11s did back in the day, I was one of three programmers on a team that developed a RSX11M based system that distributed in real time commodity trading information from the Chicago Board of Trade, The Mercantile Exchange, the COMEX and six other grain and commodity exchange to approximately 200 grain traders based all over the U.S.

The data feeds from the exchanges were funneled into a pair of PDP-11/44s connected by a DT07 bus switch and a DMC-11 (1 Mb/s). In the DT07 box, DZ11 lines read the data in and a DV11 passed DECnet traffic out to 12 PDP-11/23 or 11/24s who ran RSX11S (no disks, remote network booted). Each 11/23 located in various cities across the U.S. had around 20 serial ports and a DUV11 for DECnet. All the DECnet nodes were connected by 9600 baud AT&T lease lines.

All the code was written in Macro-11 and re-entrant Macro-11 in the 11S systems since they had to do everything in 256K of RAM. The system utilized ASTs for most everything. VT100 terminals were used and each trader could customize their screen to follow only the commodities they needed to watch. Headlines from the commodity news service scrolled across the bottom four lines. If a trader saw a headline that caught his eye, he could select it and a message would be sent back to the 11/44 to retrieve the entire story from a RMS indexed file that accumulated about 5 MB of news each day.

It was a very fun system to watch on RMD, particularly the task screens showing the network connections on various LUNs pop in and out from the various 11S data requests. I wish I still has a copy of the code, it used a lot of queues and
circular buffers to handle the data traffic when trading got busy. The traders did NOT like it when the system crashed and
the DT07 bus switch and a watch dog timer would allow the second 11/44 which was used normally used for development to be used as a backup host if the primary 11/44 failed.

Best,
Mark

Radioteacher

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Apr 17, 2021, 6:09:05 PM4/17/21
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The last PDP I saw in use was in 1995, It was in a petroleum company data center in South Texas.  The system dialed modems to access tank levels in the area and when the tank had enough for a tanker truckload it would make a ticket for the tank to be emptied.  

It was still running disk packs.

Paul

Martin Crockett

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Apr 18, 2021, 5:19:55 AM4/18/21
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Hi all,

In the early 80's I worked for the department of Further Education in South Australia and we ran a PDP11/34 with 2 x RK05 drives and a CDC multi-platter washing machine, from memory it was something like 130M; huge compared to the RK05s.

It ran RSTS/E and we had 20 or so serial terminals (VT100s).

It was used to teach programming, BASIC, pascal, Cobol, C etc..

Given it's humble specs compared to today's computers, tablets, even phones, it did extremely well.

When I get around to building my PiPD-11, I hope to try to partially recreate that environment.

Cheers, Martin...




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Neil Higgins

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Apr 18, 2021, 8:51:45 PM4/18/21
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Elsewhere in this group, I have described in somewhat more detail my employer’s use of PDP-11’s in an electricity distribution utility. We had about 30 of them, accessed initially via a statistical multiplexer, later networked via Ethernet. The real-time PDPs ran a proprietary operating system and served as our SCADA master station. The others ran TSX and provided mission critical support applications for network operation. Much of the core software was the work of just one, very clever, very dedicated person (not me, I hasten to add).

Rob Pike

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Apr 18, 2021, 9:38:37 PM4/18/21
to Neil Higgins, [PiDP-11]
My memory is foggy but I believe the 4ESS, the first digital electronic long-distance telephone switch, was a PDP-11 originally, with all the code written in assembler because 1970s.



-rob

Charley Jones

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Apr 18, 2021, 9:53:41 PM4/18/21
to Geert Rolf, [PiDP-11]
Beautifully written.  

Sent from my iPhone Xs!

On Apr 16, 2021, at 6:42 AM, Geert Rolf <geer...@gmail.com> wrote:


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Charley Jones

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Apr 18, 2021, 10:07:04 PM4/18/21
to Charley Jones, Geert Rolf, [PiDP-11]
Playing Star Trek and Zork on Altair is incredible.  Truly a time machine.


Sent from my iPhone Xs!

On Apr 18, 2021, at 6:53 PM, Charley Jones <data...@gmail.com> wrote:

Beautifully written.  

Guido De Grefte

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Apr 19, 2021, 3:06:07 PM4/19/21
to [PiDP-11]
What a great group this is! An accumulated memory of PDP11 applications from saw mills to nuclear power plants. A sentimental journey down the 2 Kbyte, 300 nsec cache memory lane, with all the affinity and warmth that good memory has to offer. So in these cold days we have found a fourth true application for this wonderful little white box: Its not just a computer, it is a small stove for sentimental souls, to warm their memories of the great days of blinking lights.

jeff.t...@gmail.com

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Apr 20, 2021, 1:17:11 AM4/20/21
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I honestly use my PiDP-11 as a beautiful Raspberry PI case, albeit running 2.1BSD with semi-legit blinkenlights.  There have been a lot of great answers already but I'll a couple of my own self-serving/BSD references:

1. I learned a little bit of PDP assembly by updating the 2.11BSD idle LED pattern.  https://groups.google.com/g/pidp-11/c/GO5BwDKiGOw/m/vX-SetK5CAAJ has some details.  It's such a useless activity, but it also feels pretty cool when you can trim an instruction or two off, then realizing that you're obsessing on making an idle LED pattern just that much more efficient on an emulated CPU that is 10x faster than real hardware.

2. How about reversing the 2.11BSD patches back to patch level 0?  Surprisingly hard to just keep up with the *new* patches (https://www.tuhs.org/Archive/Distributions/UCB/2.11BSD/Patches/ and https://github.com/chasecovello/211bsd-pidp11), but how about the patches that have disappeared from history? https://bsdimp.blogspot.com/2020/07/211bsd-original-tapes-recreation.html is a great starting place.

3. Advent Calendar.  Why not?  https://groups.google.com/g/pidp-11/c/dfByDqqofYo/m/ESLhqsy7AwAJ

Charley Jones

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Apr 20, 2021, 1:28:59 AM4/20/21
to jeff.t...@gmail.com, [PiDP-11]
I moved and can’t wait to find the retro computer box.  What a beautiful series of stories.  I cut my teeth on a pdp 8...  always dreamed of owning an Altair.  And now I do.


Sent from my iPhone Xs!

On Apr 19, 2021, at 10:17 PM, jeff.t...@gmail.com <jeff.t...@gmail.com> wrote:


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Geert Rolf

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Apr 20, 2021, 9:12:47 AM4/20/21
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This triggered a few of you to write down their memories. Great!

I focussed on PDP 11/70, that I rarely met in real life. I'll add one story about the Singer Link Miles flightsimulator for the DC-10 (not a game):

In 1977 Continental Flight Training Centre in Los Angelos got their full motion DC-10 simulator delivered. This simulator was controlled by three PDP 11/45 family systems: in fact a /50, a /55 and a real /45. That had to do with MOS fastbus memory, Bipolar fastbus memory and no fastbus memory. This simulator was later moved to Houston and retired in 2003.  Luckily it was adopted by a group of Norwegian flightsim enthousiasts and moved to Oslo area in 2004.

Some tech info: simulator software (160.000 lines of Macro including utilities) ran on RT11 v2. They had their own design Loader and Scheduler, which meant that after loading the software you have a multitasking application system, tuned to run 20 cycles per second. CPUA did all of the I/O: that is 20 times per second data in and out of the simulator hardware via a DR11-B (parrallel I/O with DMA) into a set of 16KW shared fastbus memory at CPUB. Both CPUA and CPUB ran the tasks on the data: CPUB the most at top performance. The third machine, CPUC had to drive vector graphics hardware for a Night Vision System, that we never got to work and replaced by using Microsoft FlightSimulator for just the cockpit view.

I was involved since 2008 and we replaced two of three 11/45 type machines by 11/44. CPUB being a 11/55 was the top performance machine (faster that any other genuine 11) when used the clever way, which Singer Link Miles did.


Sadly, the DC-10 simulator was scrapped in 2016. It's quite an impressive application of PDP-11s and -trust me- the PDPs were pushed to the limits of their performance.

Geert

Robert Evans

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Apr 21, 2021, 2:50:55 PM4/21/21
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This thread triggered fond memories.  I share some here ...

During the 1970's I worked for the DEC's Connecticut District at a field office supporting the RSX, IAS and VMS operating systems and associated layered products.  As a "software specialist" our duties were three-fold.  As a result of that work I remember a few things that PDP-11's were used for.

1) Provide technical support to sales.
  In addition to calling on customers with a salesman, sometimes this included converting customer applications to run on DEC hardware and running benchmarks.  For me this was typically with FORTRAN.  Fortunately, the DEC compilers could properly interpret the IBM extensions to the language.  One trick I remember is that reproducing how the IBM linker would arrange common blocks in memory could be necessary for getting the customer application to function.

  Conversion knowledge was essential to getting a Perkin-Elmer ray tracing lens design application to run on DEC HW.  They were designing lenses for spy satellites that could read license plates from low-earth orbit.  Management at Perkin-Elmer wanted the lens designers to use a minicomputer from Interdata, another division of Perkin-Elmer.  Eventually DEC got the sale because of the difficulty converting the application to Intercomp - I even was asked to document how many hours it took me to convert their application to DEC FORTRAN.

2) Warrantee work.

  If DEC software malfunctioned or did not follow the "Software Product Description" it was our job to assist the customers.  This typically was filling in a "Software Performance Report" to communicate the problem for resolution by DEC software engineering.  But also it might be simply explaining why the software actually was working correctly.

  Software installation was the majority of the warrantee work I did.  The price of a PDP-11 or VAX included installation of the hardware by DEC Field Service.  The customer also got free installation of all DEC software they purchased with the system.  When field service finished a software specialist would go on site to SYSGEN the OS and install all layered products the customer had ordered.  (VMS was preconfigured so no sysgen on VAXen.)   I was funded by DEC's "Engineering Systems Group" product line.  This meant that I called on scientific/engineering customers and only once installed COBOL or the emulator for the IBM 2780/3780 protocol emulator.  One day I had scary experience of installing those commercial products for the first time: quickly skim the installation guide,  run the install commands, then run the "Installation Verification Procedure (IVP)".  Everything seemed fine until the IVP started spewing out error messages.  I knew no COBOL.  But the customer had hired DEC not me personally.  Therefore I could telephone my backup at "Home Office Software Support".  My counterpart at H.O.S.S. saved the day by explaining that the messages were normal.  (And I've had virtually no contact with commercial software for the next 35 years of my career as a software engineer.)

  Another aspect of warrantee work was assisting with the field test of newly designed hardware.  When the VAX was new, two of the prototypes were installed at customers for evaluation.  I came along to the Schlumberger-Doll Research center with prototype #7 VAX-11/780.  This was a great opportunity for me to learn the VAX and for the customer to port their applications to the new hardware with free assistance.  I wrote weekly reports to someone in DEC HQ about the progress/problems/successes of the customer use of the new system.

  Dresser Industries of Stratford CT manufactured valves and gauges.  They would use a 36 inch wide (HP?) plotter to draw the original artwork for the scale of the gauges.  They bought an 11/70 to drive the plotter.  I first encountered them during the software installation.  Even though I consulted with them weekly for a few months, I do not remember any other applications -- for program development and plotting, I think an 11/34 would have been sufficient.

3) Software Consulting.
  We would do short-term projects of all sorts for customers.  (One of my co-workers was the system administrator at a big multi-vendor shop.  The customer even paid for him to be trained on how to run the HP minicomputers they had.)

  After the VAX-11/780 field test, Schlumberger hired me to help them convert an entire suite of their RSX-11 "Well Logging" applications to VMS.  Schlumberger does studies of the geology at well holes to assist with the location of petroleum deposits.  A tool is dropped down the shaft and it reports all sorts of measurements, porosity, tilt of the magnetic field, conductivity, natural and induced radioactivity and more.  Other applications would process, reduce and display the readings for interpretation by a geologist.  They had trucks with two PDP-11's for redundancy, video terminals, plotters and air conditioning so they could log wells and give a report the same day at places like Saudi Arabia.

  Standard Brands (now part of Nabisco) had a laboratory in Connecticut where they would test a new recipe every day.  I called on them a few times during my tenure in CT.  In the lab, there were lots of good food smells and about 3PM there were always leftovers to taste.  One day they want me to write a driver for an A-to-D converter so a test subject could turn a knob to indicate how much they liked the taste.  They ran RSX-11D.  An RSX-11D driver is simply a privileged task mapped to the I/O page.  This is the only device driver that I wrote from scratch and completed in one day.

  Norden Systems in Norwalk CT built ruggidized versions of DEC HW in smaller packages to fit aboard military vehicles.  Their 11/34M was rated for use in space.  Air cooling is not possible in a vacuum so the boards had to conduct the heat to the outside of the case where it could be radiated away.  One application they built had the 11/34M running RSX-11S on a fighter plane, involved with radar image data flow to/from a ground-based array processor.  The application details were classified and unknown by me.  However, the PDP was not booted until the fighter plane was in flight.  My role was to write a loader that would verify the checksum and downline-load the RSX-11S image to the client PDP-11.  The network HW was "equivalent" to the DMC-11, but instead of a coax cable, there was a radio link between the two PDP-11's.  I think the client used a ROM to start the boot process and I do not recall writing anything that ran on the client.  The loader I wrote was a FORTRAN program that waited for a MOP request from the client, verified the checksum of the RSX11S.TSK file and sent that file via the DMC.  Software development finished and working on genuine DEC HW, we take a field trip on April Fools day to a Sikorsky facility to test on flight HW.  Of course it did not work at first.  The HW guys had to make some last minute changes.  Everyone else had nothing to do and just stared at them while they were soldering.  Then came my turn.  The flight HW did not behave exactly like genuine DEC HW.  Everyone stared at me while I sweated and figured out what to change and modified the loader.  It all worked by the end of the day so this test was successful.  I wrote an article about the loader for a DEC publication (The Multi-tasker?) around 1980.

  Another time at Norden we started the RSX taskbuilder running with a DECtape as the scratch device.  The tape was constantly in motion until we stopped it the next day.  This demonstrates  how much I/O the taskbuilder does and/or how slow DECtape is.

After the field office
Towards the end of 1980, I transferred from the field office to DEC HQ where Ray Modeen and I wrote the SPM-11M performance monitor docs here.   Inside DEC, HW cost much less than the list price.  Ray and I had an 11/70 with FPP just for SPM.  We wrote a driver for a KW11-P to provide accurate timing info of the events logged by SPM.  Unexpected patterns in the console lights of an idle system running our monitor led to finding and fixing an obscure bug in our KW11-P driver.  Around that time DEC Field Service would routinely replace the front panel of PDP-11/70's with one for remote diagnosis, but this removed the switches and lights.  Because of the KW11-P experience, I did not allow that change and our 11/70 kept its switches and lights.  Yeah!
 
Keep those lights blinking,
-RE

Johnny Billquist

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Apr 21, 2021, 7:12:22 PM4/21/21
to [PiDP-11]
SPM-11. Now, that looked like a cool piece of software. Too bad I don't
have a copy. Nor does it seem it was ever updated to even V4 of RSX.

Anyway, as long as we're talking various uses of PDP-11s...

I assume people do know that Oracle ran on RSX in the early days. That
probably hints at a lot of usecases that we might not even imagine.

And DEC of course also had Datatrieve, which is sortof similar, but the
language for DTR isn't SQL.

And then there were Saturn systems, who provided both word processing,
spreadsheets and graphing software for RSX.

Just by looking at what software existed makes you realize that the
machines were used in many different fields...

Johnny

On 2021-04-21 20:50, Robert Evans wrote:
> This thread triggered fond memories.  I share some here ...
>
> During the 1970's I worked for the DEC's Connecticut District at a field
> office supporting the RSX, IAS and VMS operating systems and associated
> layered products.  As a "software specialist" our duties were
> three-fold.  As a result of that work I remember a few things that
> PDP-11's were used for.
>
> *1) Provide technical support to sales.*
>   In addition to calling on customers with a salesman, sometimes this
> included converting customer applications to run on DEC hardware and
> running benchmarks.  For me this was typically with FORTRAN.
> Fortunately, the DEC compilers could properly interpret the IBM
> extensions to the language.  One trick I remember is that reproducing
> how the IBM linker would arrange common blocks in memory could be
> necessary for getting the customer application to function.
>
>   Conversion knowledge was essential to getting a Perkin-Elmer ray
> tracing lens design application to run on DEC HW.  They were designing
> lenses for spy satellites that could read license plates from low-earth
> orbit.  Management at Perkin-Elmer wanted the lens designers to use a
> minicomputer from Interdata, another division of Perkin-Elmer.
> Eventually DEC got the sale because of the difficulty converting the
> application to Intercomp - I even was asked to document how many hours
> it took me to convert their application to DEC FORTRAN.
> *
> 2) Warrantee work.*
> *
> *
> *3) Software Consulting.*
> *After the field office*
> Towards the end of 1980, I transferred from the field office to DEC HQ
> where Ray Modeen and I wrote the SPM-11M performance monitor docs here
> <http://www.bitsavers.org/pdf/dec/pdp11/rsx11/SPM/>.   Inside DEC, HW
> cost much less than the list price.  Ray and I had an 11/70 with FPP
> just for SPM.  We wrote a driver for a KW11-P to provide accurate timing
> info of the events logged by SPM.  Unexpected patterns in the console
> lights of an idle system running our monitor led to finding and fixing
> an obscure bug in our KW11-P driver.  Around that time DEC Field Service
> would routinely replace the front panel of PDP-11/70's with one for
> remote diagnosis, but this removed the switches and lights.  Because of
> the KW11-P experience, I did not allow that change and our 11/70 kept
> its switches and lights.  Yeah!
> Keep those lights blinking,
> -RE
>
> --
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Robert Wilkinson

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Apr 21, 2021, 9:21:47 PM4/21/21
to [PiDP-11]
I bought a PDP-11/03 in 1978 for my first startup.  We had it in my dining room for a few months (at a time when Ken Olson insisted that nobody would want a computer in their home).  We bought a terminal whenever a new person joined the company.  Loved the VT-52, but that was replaced by VT-100 which was just too expensive for us.  So ADM-3A came to the rescue just when we needed them.

We installed TSX very early, and probably had 6 or more people working with two floppy disks.  At that time I was visiting ICL regarding the test programming work we were doing for them and on one visit I saw two 14" disks, probably 10 Mb, which they had just been evaluating.  One had been life tested and one had been environmentally tested, so they were not worth much.  I got them for a nominal amount as far as hard disks went in those days. (Might have been only 1,000 GBP ! )   I built a hardware interface for them.  A colleague built a driver, and now we had luxury !!

I think the VAX was really the start of the end for the company.  They had made their fortune with all the independent software and hardware vendors who relied on PDP-11 as the basis for their products.  As I remember (and I could be completely wrong here) when the VAX came out DEC made it much more difficult or impossible to create third party cards and wanted to supply application software themselves.  So the army of enthusiastic sales people who were selling DEC computers at no cost to DEC, now found themselves out of business.

 

Guido De Grefte

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Apr 22, 2021, 5:30:13 PM4/22/21
to [PiDP-11]
That last paragraph is an interesting business lesson!

John H. Reinhardt

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Apr 22, 2021, 5:36:53 PM4/22/21
to [PiDP-11]
On 4/21/2021 8:21 PM, Robert Wilkinson wrote:

I think the VAX was really the start of the end for the company.  They had made their fortune with all the independent software and hardware vendors who relied on PDP-11 as the basis for their products.  As I remember (and I could be completely wrong here) when the VAX came out DEC made it much more difficult or impossible to create third party cards and wanted to supply application software themselves.  So the army of enthusiastic sales people who were selling DEC computers at no cost to DEC, now found themselves out of business.


This pretty much happened when DEC introduced the BI bus as a replacement for the UNIBus and QBus with the VAX 8200/8300.  The BI was total proprietary and closed except to a few since it required special interface chips you could only get from DEC.  The PDP-11/780 through the VAX 8650 were standard UNIBus that worked the same as in the PDP.  The QBus VAXen were the same, most PDP QBus boards worked with them.

The BI bus didn't entirely shut out 3rd party boards, but it did cut them down quite a bit.

-- 
John H. Reinhardt


Johnny Billquist

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Apr 23, 2021, 8:09:32 AM4/23/21
to pid...@googlegroups.com
Yeah. And as far as I remember, the purpose of BI was really to kill off
the third party market that had sprung up with Unibus. I think there are
even a couple of quotes from KO to that effect that exist. DEC just saw
how much money they thought they lost by not selling those boards, not
considering that without those 3rd party offers, it wasn't that DEC
would sell more boards, but fewer computers.

But I sortof hate when people just say "PDP", as there are many
different ones.

The VAX sits there with the PDP-11 family. And they also used Massbus.
Massbus was also used on PDP-10.

And Unibus was used on PDP-10 and PDP-15 in addition to the PDP-11.

Qbus was/is PDP-11, VAX and MIPS.

Johnny

wjegr...@gmail.com

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Apr 23, 2021, 8:30:34 AM4/23/21
to [PiDP-11]
It was more than just the VAX, it was a pervasive attitude problem at the top. I remember interviewing at the mill out of college. Walked through one lab, there was a cool computer in a briefcase. When I expressed amazement, asked when it would be available, the answer was, "This was just a little fun project. No one would actually want one". DEC was totally convinced of their superiority, misjudged the market completely.

Johnny Billquist

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Apr 23, 2021, 9:03:12 AM4/23/21
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I think that was a completely different problem, but that was definitely
another problem they had.

DEC wanting to have more of the share of the business of their customers
was a kind of thinking that grew in the mid 80s, I'd say. Same time they
started to seriously want to become IBM. Also shown by all the IBM
management and sales staff they were taking on.

The interesting projects and products that never led anywhere seem to
have been more of a total lack of vision or understanding of the
potential of their own experiments. They had several solutions that
looks like a PC, but was never really pushed. Like the GIGI, Robin,
VT103, PDT... I know they had a portable PDP-11 with an LCD display. Not
to mention all the nice networking technology that they never
capitalized on, which lots of other companies then gained by.
Or their software. They pretty much set the benchmark for lots of
compilers and database stuff. The list goes on...

Johnny
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steve...@gmail.com

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Apr 23, 2021, 3:10:48 PM4/23/21
to [PiDP-11]

I was able to attend several DECUS meetings throughout the 80's. One of the comments amongst us technical attendees was the downward trend in the "T-shirts to ties ratio". Very few non-tech business-type attendees in the early 80's, but many more so by the end of the decade. Some of us saw it as the handwriting on the wall all the way back then.


-- steve

Google

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Apr 23, 2021, 6:15:02 PM4/23/21
to [PiDP-11]
What I think really killed DEC was KO going up against Intel with the Alpha chip.

George Marinos

gmar...@icloud.com

When thinking outside the box doesn't work any more, it's time to build a new box.



On Apr 23, 2021, at 12:10 PM, steve...@gmail.com <steve...@gmail.com> wrote:


I was able to attend several DECUS meetings throughout the 80's. One of the comments amongst us technical attendees was the downward trend in the "T-shirts to ties ratio". Very few non-tech business-type attendees in the early 80's, but many more so by the end of the decade. Some of us saw it as the handwriting on the wall all the way back then.


-- steve


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Neil Higgins

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Apr 23, 2021, 7:58:26 PM4/23/21
to [PiDP-11]
“They pretty much set the benchmark for lots of compilers and database stuff”

Not really. DEC had a very loyal following among its techie customers, probably due to the openness of their hardware, but they didn’t have a stranglehold on good software. I attended one DECUS conference where the speaker told the story of how his company, after swapping to a DECSystem20, had been forced to go through every COBOL program and shorten every variable name to six characters, because DEC didn’t support the COBOL standard. I personally had an experience of a simple but devastating bug in the RT-11 FORTRAN IV compiler. DEC leveraged their customer loyalty into arrogance, not motivation.

Johnny Billquist

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Apr 24, 2021, 7:00:22 AM4/24/21
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Well. I didn't say they had any strangle hold.
I said they set the benchmark. And that was most during the VAX/VMS
days. I can't really find many references now, but DEC pretty much did
all of FORTRAN 77 before FORTRAN 77 was even defined, but called it
FORTRAN IV-PLUS (well, this was PDP-11 stuff). (And yes, I know that
there are some differences between FIV-PLUS and F77, but if you've used
both, you know all of that...)
Also, F77 generated pretty good code. Even on the PDP-11. It has an
acceptable optimizer in there as well.

I know that I've read stories about people using Ada having a VMS
machine just to check how the language was supposed to be like, since
the VMS Ada compiler was the best reference to be found of an actual,
working implementation.

Their BASIC was better than any other ones (I know, subjective).
Especially VMS-BASIC. I can't really comment on their COBOL compiler,
since I was never in that world, or paid much attention to it.

Not sure how good their Pascal was. There were other Pascal compilers
used on DEC systems, which would suggest it wasn't that special.

On the other hand, they always had issues with the C compilers. Not sure
how much it was the compilers per se, and how much was just because
operating system differences making C a bit weird in the DEC environment.

I wouldn't take anything from the PDP-10 world as an example of
excellence in this context. While the PDP-10 stuff was nice (and some of
it rather good), it was a bit more of an odd environment when we came
into the 80s, not to mention that DEC cancelled it. Which means it
wasn't really a part of the DEC downfall (except if you look at the
cancellation as a sign of the impeding downfall itself).

Johnny

On 2021-04-24 01:58, Neil Higgins wrote:
> /“They pretty much set the benchmark for lots of compilers and database
> stuff”/
>
> Not really. DEC had a very loyal following among its techie customers,
> probably due to the openness of their hardware, but they didn’t have a
> stranglehold on good software. I attended one DECUS conference where the
> speaker told the story of how his company, after swapping to a
> DECSystem20, had been forced to go through every COBOL program and
> shorten every variable name to six characters, because DEC didn’t
> support the COBOL standard. I personally had an experience of a simple
> but devastating bug in the RT-11 FORTRAN IV compiler. DEC leveraged
> their customer loyalty into arrogance, not motivation.
> On Saturday, 24 April 2021 at 08:15:02 UTC+10 gmarin...@gmail.com wrote:
>
> What I think really killed DEC was KO going up against Intel with
> the Alpha chip.
>
> George Marinos
>
> gmar...@icloud.com
>
> When thinking outside the box doesn't work any more, it's time to
> build a new box.
>
>
>
>> On Apr 23, 2021, at 12:10 PM, steve...@gmail.com
>> <http://gmail.com> <steve...@gmail.com> wrote:
>>
>>
>> I was able to attend several DECUS meetings throughout the 80's.
>> One of the comments amongst us technical attendees was the
>> downward trend in the "T-shirts to ties ratio". Very few non-tech
>> business-type attendees in the early 80's, but many more so by the
>> end of the decade. Some of us saw it as the handwriting on the
>> wall all the way back then.
>>
>>
>> -- steve
>>
>>
>> --
>> You received this message because you are subscribed to the Google
>> Groups "[PiDP-11]" group.
>> To unsubscribe from this group and stop receiving emails from it,
>> send an email to pidp-11+u...@googlegroups.com.
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>
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Johnny Billquist

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Apr 24, 2021, 7:54:35 AM4/24/21
to pid...@googlegroups.com
By the way, DEC was doing a common backend for all of their compilers
already in the 80s. Something others are doing now.

It was/is called GEM, and it was really ahead of its time. So in the
late 80s into the 90s, DEC really had a lot of really good software.
Which they really didn't manage to capitalize on.

If we're talking about why DEC failed, not capitalizing on all they good
things that existed inside DEC is very relevant. And software was one
big component of that. They also had some really good hardware.
Understand that DEC did gigabit network switches in the 90s. When did
companies and equipment start doing gigabit networking outside?
The GIGAswitch family of solutions were announced in 1992.

To make a small comment on Alpha, I seriously doubt that it was the
reason for the downfall. However, DECs traditional approach to hamstring
themselves in order to not outcompete themselves, and trying to maximize
profits certainly helped lead to the downfall of the Alpha.
Having different PALcode for Windows NT compared to VMS, and having some
Alpha chips that could only have one other the other PALcode, as well as
making it hard for third parties to build systems with Alphas... Sortof
the same reasoning that lead to VAXBI.

They had a pretty good offerings for disks for a while as well, before
messing that piece up.

And don't forget things like AltaVista. Heck, even Google extracted
people and knowhow from the ruins of DEC. Some of the foundational work
at Google can be traced back to work at DEC.

Johnny

John Anderson

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Apr 24, 2021, 11:31:23 AM4/24/21
to Johnny Billquist, pid...@googlegroups.com

On Apr 24, 2021, at 4:54 AM, Johnny Billquist <b...@softjar.se> wrote:

To make a small comment on Alpha, I seriously doubt that it was the reason for the downfall. However, DECs traditional approach to hamstring themselves in order to not outcompete themselves, and trying to maximize profits certainly helped lead to the downfall of the Alpha.
Having different PALcode for Windows NT compared to VMS, and having some Alpha chips that could only have one other the other PALcode, as well as making it hard for third parties to build systems with Alphas... Sortof the same reasoning that lead to VAXBI.

Back in the day, when Microsoft was doing NT I was a developer and a few things struck me about the Alpha:

-Almost nobody at Microsoft used them.
-If was impossible to buy one from DEC. They never understood the PC market.
-It was a far superior architecture to Intel and still is.


They had a pretty good offerings for disks for a while as well, before messing that piece up.

And don't forget things like AltaVista. Heck, even Google extracted people and knowhow from the ruins of DEC. Some of the foundational work at Google can be traced back to work at DEC.

Having been in the startup scene in the Valley since working for Steve Jobs at NeXT and various other startups, AltaVista was a big deal in the day day. They could have become Google if they wanted to.

DEC much more than any other company I know of created the computing architectures we use today.

Bill Saltzstein

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Apr 26, 2021, 1:00:00 AM4/26/21
to Guido De Grefte, [PiDP-11]
Hi Guido,
  Your beautiful story has had me thinking about an old photograph, and I finally found it, attached.  Here’s the story if you’re interested in a read.  Grab a cup of tea, coffee, beer, wine, or whatever; it got longer than I’d intended.

  I was a freshman or sophomore (1st or 2nd year of 4, for our non-US friends) in high school, and discovered an ASR-33 terminal in the back room that was very recently connected via (300 baud) modem.  The teacher told me that it had been recently installed by the local University (University of Wisconsin, Milwaukee) as a test and he knew little about it, but there was a binder of instructions and I was welcome to come try it after class.  It was a dial-in to what I later learned was a TSS/8 system being modified by a Graduate Student and I could write programs (in BASIC) and we had some limited program storage to save small programs.  Larger ones were to be saved on paper tape so others would have room.

  I was hooked!  Later, I would ride my bicycle to the University Computer Lab and beg the graduate student to let me hang out and watch.  After that, I was ‘allowed’ to hang DECtapes and hand out the line printer outputs when other students came by.  I became their first and only high school computer operator and even had regular (unpaid) hours that I’d work.  In exchange, I got to play with the system in privileged mode, read documentation, and see the machine in OS/8 mode.  I was able to write stand-alone PDP-8 Assembly programs and could decode ASCII paper tape.  As you can see by this photo, I was in heaven!

  As an incentive to keep engaged and learning, my parents let me enroll in a few college computer classes (yeah, I was one of those kids).  I learned (a bit of) COBOL and FORTRAN on the UNIVAC using punched cards.

  I graduated and went to college at the University of Rochester (NY).  There, as an Electrical Engineering student, I studied Computer Architecture and Systems and took Computer classes (this was before their formal Computer Science department began) in Pascal and Assembler on their brand-new water-cooled IBM (it was Rochester).  I programmed (for pay this time) in FORTRAN on a PDP-11/70 running BSD UNIX for a group working on an early CAD system.

  In later years I did hardware interface work to a medical ultrasound machine at the medical school with an S-100 card and programmed in FORTH, and eventually saw that work ported to a Data General NOVA.

  Out of school I joined HP and initially worked on an integrated circuit for the magnetic card reader for a handheld BASIC computer (HP-71).  I’d come full circle, but now had the whole BASIC computer in my hands.

  There is a lot more after that, but I didn’t touch a DEC computer again.  Fast forward many, many years.

   I bought the SBC6120 kit when that was offered.  I didn’t build it right away, and even then didn’t have time or interest to do much with it.  Fast forward some more years.  COVID and the funding challenges of the medical device startup companies I was working for as a consultant gave me a bit of opportunity.  I built Oscar’s PiDP-11 and then a PiDP-8 that I also had purchased and got them up and running.

  Then I discovered Sytse’s PDP2011 and got that running on Oscar’s kit (and am still working with his wonderful FPGAs).

  My primary setup today is a VT-420 that has two sessions: one to the SBC6120 running OS/8 and the other session is the FPGA-based PDP-11/70 running BSD Unix.  I love the PiDP machines, but somehow the “hardware-based” implementations call my name...

  Long story, but the same punchline as Guido so beautifully stated to his daughter.  Look at the photograph of the kid I was and read Guido's words slightly paraphrased: “This is a time machine. This was once a machine that brought _me_ the future and now this little box can send me back to when I was _that_ age.”

  Thanks to all of you who help build time machines: Oscar, Sytse, and everyone who builds and operates time machines.
 
Take care,
Bill Saltzstein






On Apr 15, 2021, at 2:26 PM, Guido De Grefte <gdeg...@gmail.com> wrote:

It is dark outside when I first turn on the lights. Silently the black panel stares back at me. Just before doubt creeps in, the first red dots signal life, progress, hope. Solidly soldered, 64 blinking leds proudly next to the arrogant 5120 x 2880 retina screen where this text is displayed. Small, in this humble plum color next to her shining and shouting 27 inch neighbour.  “But what can it do?”, people ask. “It can’t do much, but it has done a lot.” would be the proper response. “It has changed the world”. Looking at these blinking lights is like looking at the birth of a star. Don’t look at what it is, look at what it can become. Yes, we see progress. But above all, we see promise.

The background of my VNC-desktop is a picture of a woman in front of a PDP-11. She looks like my mother when I was 11 years old, in a jumpsuit and Brigitte Bardot hair. She holds a card, probably the programming card for her ‘family of PDP-11 computers’, the same one as I am holding now. And I guess she is keying in the bootloader of the program that would run, evolve and grow into the digital life as we know it. I manually toggle in a bootloader on the PiDP-11. Then my daughter looks over my shoulder and asks: “What are you doing?”. I answer: “This is a time machine. This was once a machine that brought us the future and now this little box can send me back to when I was your age.”

Then I search the PiDP11-forum for the key switch. I want to make sure that I don’t misunderstand the purpose of this key, which is in my build is actually doing, well, nothing. It is reassuring to find that this is indeed the first key I’ve ever owned that I don’t need to worry about loosing. It is proof of the proud name that Oscar has chosen for his company. Further browsing the forum for other facts and feedback that I could perfectly live without, I notice something unusual. People are nice. They are not in a hurry. There is no judgement. They find time to build a kit with their children and enjoy every little 8th bit of it, including the bubbly plastic. On this forum the people take the time to write whole words to express emoticons, and to make mild jokes without brute force. So when people ask: “But what can this thing do?”, the answer could be: “It is a miracle machine, it brings out the best in people!”

A big thank you for everybody who made this possible, specially for Oscar who has made this wonderfull kit and my wonderfull wife who bought this for my birthday.

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Charley Jones

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Apr 26, 2021, 1:38:13 AM4/26/21
to Bill Saltzstein, Guido De Grefte, [PiDP-11]
Not to mention the 1970’s Era Dr Who Scarf you’re touting.
I was always a Tom Baker fan.
Snuck time onto the SMU (Southeastern Massachusetts University) computer.
Never leave the admin password written inside the maintenance manual, lol.
-crj


On Apr 25, 2021, at 9:59 PM, Bill Saltzstein <bills...@gmail.com> wrote:

Hi Guido,
  Your beautiful story has had me thinking about an old photograph, and I finally found it, attached.  Here’s the story if you’re interested in a read.  Grab a cup of tea, coffee, beer, wine, or whatever; it got longer than I’d intended.

  I was a freshman or sophomore (1st or 2nd year of 4, for our non-US friends) in high school, and discovered an ASR-33 terminal in the back room that was very recently connected via (300 baud) modem.  The teacher told me that it had been recently installed by the local University (University of Wisconsin, Milwaukee) as a test and he knew little about it, but there was a binder of instructions and I was welcome to come try it after class.  It was a dial-in to what I later learned was a TSS/8 system being modified by a Graduate Student and I could write programs (in BASIC) and we had some limited program storage to save small programs.  Larger ones were to be saved on paper tape so others would have room.

  I was hooked!  Later, I would ride my bicycle to the University Computer Lab and beg the graduate student to let me hang out and watch.  After that, I was ‘allowed’ to hang DECtapes and hand out the line printer outputs when other students came by.  I became their first and only high school computer operator and even had regular (unpaid) hours that I’d work.  In exchange, I got to play with the system in privileged mode, read documentation, and see the machine in OS/8 mode.  I was able to write stand-alone PDP-8 Assembly programs and could decode ASCII paper tape.  As you can see by this photo, I was in heaven!

  As an incentive to keep engaged and learning, my parents let me enroll in a few college computer classes (yeah, I was one of those kids).  I learned (a bit of) COBOL and FORTRAN on the UNIVAC using punched cards.

  I graduated and went to college at the University of Rochester (NY).  There, as an Electrical Engineering student, I studied Computer Architecture and Systems and took Computer classes (this was before their formal Computer Science department began) in Pascal and Assembler on their brand-new water-cooled IBM (it was Rochester).  I programmed (for pay this time) in FORTRAN on a PDP-11/70 running BSD UNIX for a group working on an early CAD system.

  In later years I did hardware interface work to a medical ultrasound machine at the medical school with an S-100 card and programmed in FORTH, and eventually saw that work ported to a Data General NOVA.

  Out of school I joined HP and initially worked on an integrated circuit for the magnetic card reader for a handheld BASIC computer (HP-71).  I’d come full circle, but now had the whole BASIC computer in my hands.

  There is a lot more after that, but I didn’t touch a DEC computer again.  Fast forward many, many years.

   I bought the SBC6120 kit when that was offered.  I didn’t build it right away, and even then didn’t have time or interest to do much with it.  Fast forward some more years.  COVID and the funding challenges of the medical device startup companies I was working for as a consultant gave me a bit of opportunity.  I built Oscar’s PiDP-11 and then a PiDP-8 that I also had purchased and got them up and running.

  Then I discovered Sytse’s PDP2011 and got that running on Oscar’s kit (and am still working with his wonderful FPGAs).

  My primary setup today is a VT-420 that has two sessions: one to the SBC6120 running OS/8 and the other session is the FPGA-based PDP-11/70 running BSD Unix.  I love the PiDP machines, but somehow the “hardware-based” implementations call my name...

  Long story, but the same punchline as Guido so beautifully stated to his daughter.  Look at the photograph of the kid I was and read Guido's words slightly paraphrased: “This is a time machine. This was once a machine that brought _me_ the future and now this little box can send me back to when I was _that_ age.”

  Thanks to all of you who help build time machines: Oscar, Sytse, and everyone who builds and operates time machines.
 
Take care,
Bill Saltzstein

<Bill and PDP-8 at UWM.jpeg>





On Apr 15, 2021, at 2:26 PM, Guido De Grefte <gdeg...@gmail.com> wrote:

It is dark outside when I first turn on the lights. Silently the black panel stares back at me. Just before doubt creeps in, the first red dots signal life, progress, hope. Solidly soldered, 64 blinking leds proudly next to the arrogant 5120 x 2880 retina screen where this text is displayed. Small, in this humble plum color next to her shining and shouting 27 inch neighbour.  “But what can it do?”, people ask. “It can’t do much, but it has done a lot.” would be the proper response. “It has changed the world”. Looking at these blinking lights is like looking at the birth of a star. Don’t look at what it is, look at what it can become. Yes, we see progress. But above all, we see promise.

The background of my VNC-desktop is a picture of a woman in front of a PDP-11. She looks like my mother when I was 11 years old, in a jumpsuit and Brigitte Bardot hair. She holds a card, probably the programming card for her ‘family of PDP-11 computers’, the same one as I am holding now. And I guess she is keying in the bootloader of the program that would run, evolve and grow into the digital life as we know it. I manually toggle in a bootloader on the PiDP-11. Then my daughter looks over my shoulder and asks: “What are you doing?”. I answer: “This is a time machine. This was once a machine that brought us the future and now this little box can send me back to when I was your age.”

Then I search the PiDP11-forum for the key switch. I want to make sure that I don’t misunderstand the purpose of this key, which is in my build is actually doing, well, nothing. It is reassuring to find that this is indeed the first key I’ve ever owned that I don’t need to worry about loosing. It is proof of the proud name that Oscar has chosen for his company. Further browsing the forum for other facts and feedback that I could perfectly live without, I notice something unusual. People are nice. They are not in a hurry. There is no judgement. They find time to build a kit with their children and enjoy every little 8th bit of it, including the bubbly plastic. On this forum the people take the time to write whole words to express emoticons, and to make mild jokes without brute force. So when people ask: “But what can this thing do?”, the answer could be: “It is a miracle machine, it brings out the best in people!”

A big thank you for everybody who made this possible, specially for Oscar who has made this wonderfull kit and my wonderfull wife who bought this for my birthday.

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Martin Crockett

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Apr 26, 2021, 5:13:02 AM4/26/21
to Bill Saltzstein, Guido De Grefte, [PiDP-11]
Hi BIll,

Great story..

Cheers, Martin...

Peter campbell-burns

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Apr 26, 2021, 5:23:35 PM4/26/21
to [PiDP-11]
My first encounter with PDP 11s was in my university's programming laboratory.  There were two interconnected PDP 11th running an operating system developed by the university specifically for the the students and it was here that I first learned to program in Macro 11.  

It is thanks to this experience that I had a successful interview for role of programmer analyst within another university's physics department.  The department ran two PDP 11s, two Vax systems and a GEC 4085.  Most of my programming work was to develop data acquisition software for high energy physics experiments conducted at CERN including digitisation of bubble chamber photographs.  Almost all of this work was done in FORTRAN and Macro 11 running under RSX11-M.; BESY measuring tables were interfaced to one of the PDP-11s via CAMAC modules.   As well as programming I helped with system management and keeping the systems running.  I can remember the occasional long night running SYSGENs and installing DECNET.  I had forgotten just how much I loved working with the PDP-11s.  I miss watching the tape reels turn, the scream of the line printer and manhandling disk packs.  

Despite amazing advances in technology I just can't fall in love with the modern computer in the way that I did with the PDP-11.  Oscar has done an amazing job of recreating that wonderful tactile feel of these amazing old  

So now that I have built my PiDP-11 what can it do?  To try bring back long forgotten RSX11 skills I am writing some software to simulate the dark flight of meteors using data from the UK meteor observation network, however I would dearly love to get my hands on some of the bubble chamber digitisation software I developed back in the 1980s.  Keeping the Pi based PiDP-11 company is a PDP-2011 which, so far, I have not done much with.

Johnny Billquist

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Apr 26, 2021, 5:32:44 PM4/26/21
to pid...@googlegroups.com
As for what your PiDP-11 can do; if you run RSX, I'd recommend the
latest RSX-11M-PLUS, and then install TCPIP
(http://mim.update.uu.se/tcpip.htm) and RPM
(http://mim.update.uu.se/rpm.htm), then install compilers, tools,
utilities and whatever else fun you feel like.
Manuals can be found at http://mim.update.uu.se/manuals/

Johnny
> and read Guido's words slightly paraphrased: /“This is a time
> machine. This was once a machine that brought _me_ the future
> and now this little box can send me back to when I was _that_ age.”/
> /
> /
>   Thanks to all of you who help build time machines: Oscar,
> Sytse, and everyone who builds and operates time machines.
> Take care,
> Bill Saltzstein
> bills...@gmail.com
>
>
>
>
>
>
>> <https://groups.google.com/d/msgid/pidp-11/0d4f76cb-293d-44e8-ae35-a95993d642b8n%40googlegroups.com?utm_medium=email&utm_source=footer>.
>
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>
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> <https://groups.google.com/d/msgid/pidp-11/B799AF19-1906-4F1F-9B48-28FA84F38D89%40gmail.com?utm_medium=email&utm_source=footer>.
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Bill Saltzstein

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Apr 26, 2021, 9:02:52 PM4/26/21
to Johnny Billquist, pid...@googlegroups.com
Hi Johnny,
Would you happen to have a complete and updated bootable 11/70 RP06 image I could ‘leverage’? I’d love to use one that an expert has put together and properly configured for the PDP-2011 setup.

I know that’s a big ask, but if you happen to have one, I’d really like it. I’ve got a ‘decent’ one running, but always happy to add to my library.

Thanks either way,
Bill
> To view this discussion on the web visit https://groups.google.com/d/msgid/pidp-11/b83581c0-1577-fe2c-38a7-c69ed6448331%40softjar.se.

Johnny Billquist

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Apr 27, 2021, 5:36:00 AM4/27/21
to Bill Saltzstein, pid...@googlegroups.com
I don't have any prepared, but since I have promised Oscar for a long
time that I should create one, I guess it's about time I do.
I'll try to find time this weekend...

With that said, I seem to remember that the PDP-2011 don't have FPP. Am
I remembering that right? If so, it certainly put some limits on what
tools and things you might be able to use.

Johnny

Ron Pool

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Apr 27, 2021, 7:50:51 AM4/27/21
to Johnny Billquist, Bill Saltzstein, pid...@googlegroups.com
Sytse van Slooten's PDP2011 has an optional FPP, but when you configure it for "modelcode = 70" these features are included:

11/70 system, 22-bit MMU (3-bit ACF),FPU,Unibus map

The FPP is included by default for a PDP2011 11/70, but that feature can be left out when building if you prefer.

For PDP2011 FPGA configuration options, see https://pdp2011.sytse.net/wordpress/howto/configuration/

-- Ron



Johnny Billquist

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Apr 27, 2021, 8:00:17 AM4/27/21
to Ron Pool, Bill Saltzstein, pid...@googlegroups.com
Cool. I'm clearly not up to date on what Sytse's been up to. But good
news...
Now, my only gripe is that I like big disks... :-)

Johnny

Bill Saltzstein

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Apr 27, 2021, 11:30:02 AM4/27/21
to Johnny Billquist, Ron Pool, pid...@googlegroups.com
Thanks Ron — yes, my PDP2011 is configured as a PDP 11/70 with FPU and an RH controller (for RP06 disks). The RP06 are pretty large for the era. I’m working to put a 2nd controller on it (waiting for another SD card PMOD to arrive), but that will be a different controller (likely RL or RK).

Let us all know if you’re willing/able to put together an RP image, it would be great!

Thanks,
Bill

Johnny Billquist

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Apr 27, 2021, 5:04:42 PM4/27/21
to pid...@googlegroups.com
Well, the RP06 was pretty okay in the early days of the 11/70, but you
also had the RM05 and RP07, which were definitely bigger.
And once MSCP came, the game changed. MSCP allows for up to 2TB disk
size. However, RSX currently have a limit of 8GB. But I am actually
running with 8GB disks on my RSX systems, and using quite a lot of it.
(Disks larger than 8GB will be truncated to 8GB in RSX. There is also
code to handle larger disks, but I haven't tested yet how complete it is...)

Johnny

Bill Saltzstein

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Apr 27, 2021, 5:21:24 PM4/27/21
to Johnny Billquist, pid...@googlegroups.com
Thanks Johnny!

I sent Sytse a note to find out if there are any higher capacity drives supported by the the PDP2011 VHDL controllers; I don’t know if he follows this email group. Certainly not the same issue with the simh PiDP implementations, but it would be great to allow a small ‘footprint’ implementation if possible.

Bill
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Johnny Billquist

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Apr 27, 2021, 5:36:26 PM4/27/21
to Bill Saltzstein, pid...@googlegroups.com
Oh, no worry. Personally I don't really have time to play with a PDP2011
anyway, so it was mostly a reflection of a wish on my side based on my
own patterns. I know Sytse somewhat, and have exchanged lots of mails
with him. As far as I know, no larger disk is in the pipeline at the
moment. It might be that the RM05 and RP07 would already be possible,
since they are also hooked to the same RH controller.

Another possible device would be the RM06. This is a disk that was made
by Setasi in the late 80s. Also massbus, but it's actually variable in
size, so it would be possible to get very big disks that way.

If I had one in real life, it would be very nice, since the RH70 is way
faster than any Unibus controller, and Updates 11/70 currently is
running with an UDA50 and four RA73 drives (2 GB each).

But finding an RM06 today seems unlikely... But it be a potentially
interesting drive to support by Sytse. RSX have support for it, but I
don't know about other PDP-11 OSes.

Johnny

Bill Saltzstein

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Apr 27, 2021, 8:11:46 PM4/27/21
to Johnny Billquist, pid...@googlegroups.com
From Sytse’s web site for the PDP2011, under limitations: 
  • The RH controller for the RP/RM disks can only support 1 disk drive, and it has only really been tested with RP06 images.
I was ’talking’ with him about RP04 support, and he showed me where to change this in the top level VHDL:       rh_type : in integer range 4 to 7 := 6;

I believe that changing this to rh_type :=7 would indeed enable an RP07, so if that works for you, go ahead and I’ll be very willing to test the disk image once you’re happy with it using simh.

Thanks,
Bill

Sytse van Slooten

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Apr 28, 2021, 11:50:56 AM4/28/21
to Bill Saltzstein, Johnny Billquist, pid...@googlegroups.com
Hi Bill (and Johnny)

Ah, for some weird reason your other message ended up in my spam box ;-) and yes, I follow this group but not always daily.

Currently the biggest disk would be rp07 - but that's hardly been tested. Maybe I should try to do that - looks like there's a spell of rain coming up next week ;-)
And there's also the bit of unfinished work on supporting multiple drives, but that will likely take longer.

I'm not sure I've ever seen any info on rm06 and neither could I find any with a quick scan on bitsavers... so rp07 is the best bet for the short term, if rp06 is not big enough.


Sytse van Slooten

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Apr 28, 2021, 11:56:00 AM4/28/21
to Johnny Billquist, Ron Pool, Bill Saltzstein, pid...@googlegroups.com
The fpp has been there from the start - well, before the whole thing started running bsd and rsx properly.

You might be confused by that I used to have a build without it, so that it would fit one of the smaller fpga boards - more specifically, the one that I used to run my home automation on ;-)
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Johnny Billquist

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Apr 28, 2021, 12:14:14 PM4/28/21
to Sytse van Slooten, Bill Saltzstein, pid...@googlegroups.com
Sytse, the RM05 should be easy enough to also find information about,
and it's also bigger than an RP06.

The problem with the RP07 was that the support was somewhat spotty on
the PDP-11. Technically, only the PDP-11/70 can support it, and while I
did run one for a while, I needed to fix some things in RSX for it. FMT
for example don't actually have a module for formatting an RP07. There
is just a placeholder there.

RM06 is not a DEC drive. And I do not have any proper documentation
about the drive, but I can figure out any details needed by looking at
the RSX code, if you are interested.

Searching a bit, it seems RM06 was the designation if it used an optical
drive, and RP12 if it was spinning rust.
See http://www.corestore.org/rp12.htm for a little bit of information.

Johnny

On 2021-04-28 17:50, Sytse van Slooten wrote:
> Hi Bill (and Johnny)
>
> Ah, for some weird reason your other message ended up in my spam box ;-)
> and yes, I follow this group but not always daily.
>
> Currently the biggest disk would be rp07 - but that's hardly been
> tested. Maybe I should try to do that - looks like there's a spell of
> rain coming up next week ;-)
> And there's also the bit of unfinished work on supporting multiple
> drives, but that will likely take longer.
>
> I'm not sure I've ever seen any info on rm06 and neither could I find
> any with a quick scan on bitsavers... so rp07 is the best bet for the
> short term, if rp06 is not big enough.
>
>
>> On 28 Apr 2021, at 02:11, Bill Saltzstein <bills...@gmail.com
>> <mailto:bills...@gmail.com>> wrote:
>>
>> From Sytse’s web site for the PDP2011, under limitations:
>>
>> * The RH controller for the RP/RM disks can only support 1 disk
>> drive, and it has only really been tested with RP06 images.
>>
>> I was ’talking’ with him about RP04 support, and he showed me where to
>> change this in the top level VHDL:       rh_type : in integer range 4
>> to 7 := 6;
>>
>> I believe that changing this to rh_type :=7 would indeed enable an
>> RP07, so if that works for you, go ahead and I’ll be very willing to
>> test the disk image once you’re happy with it using simh.
>>
>> Thanks,
>> Bill
>>
>>> On Apr 27, 2021, at 2:36 PM, Johnny Billquist <b...@softjar.se
>>>>> <mailto:b...@softjar.se>> wrote:
>>>>>
>>>>> Well, the RP06 was pretty okay in the early days of the 11/70, but
>>>>> you also had the RM05 and RP07, which were definitely bigger.
>>>>> And once MSCP came, the game changed. MSCP allows for up to 2TB
>>>>> disk size. However, RSX currently have a limit of 8GB. But I am
>>>>> actually running with 8GB disks on my RSX systems, and using quite
>>>>> a lot of it.
>>>>> (Disks larger than 8GB will be truncated to 8GB in RSX. There is
>>>>> also code to handle larger disks, but I haven't tested yet how
>>>>> complete it is...)
>>>>>
>>>>>  Johnny
>>>>>
>>>>> On 2021-04-27 17:29, Bill Saltzstein wrote:
>>>>>> Thanks Ron — yes, my PDP2011 is configured as a PDP 11/70 with FPU
>>>>>> and an RH controller (for RP06 disks).  The RP06 are pretty large
>>>>>> for the era.  I’m working to put a 2nd controller on it (waiting
>>>>>> for another SD card PMOD to arrive), but that will be a different
>>>>>> controller (likely RL or RK).
>>>>>> Let us all know if you’re willing/able to put together an RP
>>>>>> image, it would be great!
>>>>>> Thanks,
>>>>>> Bill
>>>>>>> On Apr 27, 2021, at 5:00 AM, Johnny Billquist <b...@softjar.se
>>>>>>> <mailto:b...@softjar.se>> wrote:
>>>>>>>
>>>>>>> Cool. I'm clearly not up to date on what Sytse's been up to. But
>>>>>>> good news...
>>>>>>> Now, my only gripe is that I like big disks... :-)
>>>>>>>
>>>>>>>  Johnny
>>>>>>>
>>>>>>> On 2021-04-27 13:50, Ron Pool wrote:
>>>>>>>> Sytse van Slooten's PDP2011 has an optional FPP, but when you
>>>>>>>> configure it for "modelcode = 70" these features are included:
>>>>>>>>     11/70 system, 22-bit MMU (3-bit ACF),FPU,Unibus map
>>>>>>>> The FPP is included by default for a PDP2011 11/70, but that
>>>>>>>> feature can be left out when building if you prefer.
>>>>>>>> For PDP2011 FPGA configuration options, see
>>>>>>>> https://pdp2011.sytse.net/wordpress/howto/configuration/
>>>>>>>> <https://pdp2011.sytse.net/wordpress/howto/configuration/>
>>>>>>>> -- Ron
>>>>>>>
>>>>>>> --
>>>>>>> Johnny Billquist                  || "I'm on a bus
>>>>>>>                                  ||  on a psychedelic trip
>>>>>>> email: b...@softjar.se <mailto:b...@softjar.se>             ||
>>>>>>>  Reading murder books
>>>>>>> pdp is alive!                     ||  tryin' to stay hip" - B. Idol
>>>>>
>>>>> --
>>>>> Johnny Billquist                  || "I'm on a bus
>>>>>                                  ||  on a psychedelic trip
>>>>> email: b...@softjar.se <mailto:b...@softjar.se>             ||
>>>>>  Reading murder books
>>>>> pdp is alive!                     ||  tryin' to stay hip" - B. Idol
>>>>>
>>>>> --
>>>>> You received this message because you are subscribed to the Google
>>>>> Groups "[PiDP-11]" group.
>>>>> To unsubscribe from this group and stop receiving emails from it,
>>>>> send an email to pidp-11+u...@googlegroups.com
>>>>> <mailto:pidp-11+u...@googlegroups.com>.
>>>>> <https://groups.google.com/d/msgid/pidp-11/30f43a13-7d31-6c9a-c470-131397cd60d6%40softjar.se>.
>>>
>>> --
>>> Johnny Billquist                  || "I'm on a bus
>>>                                  ||  on a psychedelic trip
>>> email: b...@softjar.se <mailto:b...@softjar.se>             ||  Reading
>>> murder books
>>> pdp is alive!                     ||  tryin' to stay hip" - B. Idol
>>
>>
>> --
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Johnny Billquist

unread,
Apr 28, 2021, 12:21:28 PM4/28/21
to Sytse van Slooten, Ron Pool, Bill Saltzstein, pid...@googlegroups.com
Am I confusing you with someone else then? Who was it that sorted out
the FPP simulation in 2.11BSD because he didn't have an FPP?

Johnny

Sytse van Slooten

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Apr 28, 2021, 12:41:06 PM4/28/21
to Johnny Billquist, Ron Pool, Bill Saltzstein, pid...@googlegroups.com

Johnny Billquist

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Apr 28, 2021, 1:19:00 PM4/28/21
to Sytse van Slooten, Ron Pool, Bill Saltzstein, pid...@googlegroups.com
Ah! Yes. Now that you mention the name, it comes back. So sorry for
confusing you two.

Johnny

On 2021-04-28 18:41, Sytse van Slooten wrote:
> That's Walther Mueller: https://wfjm.github.io/home/
> <https://wfjm.github.io/home/>w11/
>
>> On 28 Apr 2021, at 18:21, Johnny Billquist <b...@softjar.se
>> <mailto:b...@softjar.se>> wrote:
>>
>> Am I confusing you with someone else then? Who was it that sorted out
>> the FPP simulation in 2.11BSD because he didn't have an FPP?
>>
>>  Johnny
>>
>> On 2021-04-28 17:55, Sytse van Slooten wrote:
>>> The fpp has been there from the start - well, before the whole thing
>>> started running bsd and rsx properly.
>>> You might be confused by that I used to have a build without it, so
>>> that it would fit one of the smaller fpga boards - more specifically,
>>> the one that I used to run my home automation on ;-)
>>>> On 27 Apr 2021, at 14:00, Johnny Billquist <b...@softjar.se
>>>> <mailto:b...@softjar.se>> wrote:
>>>>
>>>> Cool. I'm clearly not up to date on what Sytse's been up to. But
>>>> good news...
>>>> Now, my only gripe is that I like big disks... :-)
>>>>
>>>>  Johnny
>>>>
>>>> On 2021-04-27 13:50, Ron Pool wrote:
>>>>> Sytse van Slooten's PDP2011 has an optional FPP, but when you
>>>>> configure it for "modelcode = 70" these features are included:
>>>>>     11/70 system, 22-bit MMU (3-bit ACF),FPU,Unibus map
>>>>> The FPP is included by default for a PDP2011 11/70, but that
>>>>> feature can be left out when building if you prefer.
>>>>> For PDP2011 FPGA configuration options, see
>>>>> https://pdp2011.sytse.net/wordpress/howto/configuration/
>>>>> <https://pdp2011.sytse.net/wordpress/howto/configuration/>
>>>>> -- Ron
>>>>
>>>> --
>>>> Johnny Billquist                  || "I'm on a bus
>>>>                                  ||  on a psychedelic trip
>>>> email: b...@softjar.se <mailto:b...@softjar.se>             ||
>>>>  Reading murder books
>>>> pdp is alive!                     ||  tryin' to stay hip" - B. Idol
>>>>
>>>> --
>>>> You received this message because you are subscribed to the Google
>>>> Groups "[PiDP-11]" group.
>>>> To unsubscribe from this group and stop receiving emails from it,
>>>> send an email to pidp-11+u...@googlegroups.com
>>>> <mailto:pidp-11+u...@googlegroups.com>.
>>>> <https://groups.google.com/d/msgid/pidp-11/60bf851a-3deb-bfc0-c43f-2fc2148bcdde%40softjar.se>.
>>
>> --
>> Johnny Billquist                  || "I'm on a bus
>>                                  ||  on a psychedelic trip
>> email: b...@softjar.se <mailto:b...@softjar.se>             ||  Reading
>> murder books
>> pdp is alive!                     ||  tryin' to stay hip" - B. Idol
>>
>> --
>> You received this message because you are subscribed to the Google
>> Groups "[PiDP-11]" group.
>> To unsubscribe from this group and stop receiving emails from it, send
>> an email to pidp-11+u...@googlegroups.com
>> <mailto:pidp-11+u...@googlegroups.com>.
>> To view this discussion on the web visit
>> https://groups.google.com/d/msgid/pidp-11/618608f1-7e17-98ae-35da-e67549759d57%40softjar.se
>> <https://groups.google.com/d/msgid/pidp-11/618608f1-7e17-98ae-35da-e67549759d57%40softjar.se>.
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