The PDP-11/34 and two working RL-01 drives running RT-11 (ver5.03) opperating system. The RL-01 drives are 5 Mb each and this system has a total of 128K of memory.
That's a marvelous set-up you have there! 👍 It really brings back memories. In the late 70's, I was a Research Specialist for NASA and the McDonnell Center for Space Sciences at Washingyon University in St. Louis. I maintained and programmed two PDP-11/34 systems running RSX-11M. One of them did scientific calculations, and the other drove a Tracor-Northern automation system of a JEOL JXA-733 scanning electron microscope / X-ray analyzer. The TN system used a microprocessor that was a PDP-8 emulator. Great machines! BTW, about 4 or 5 years after that, I bought a VAX-11/730 for my personal home computer. 🙂
The likelihood is that an old device wouldn't work right, so you'd have to learn the hardware and software and work long hours to fix it... Some people do find that fun.
I remember operating this exact same system in 1982 at Security Bank of Nevada (now defunct). I worked in the trust department and I not only ran the system, but also had to do data entry and print out statements. The bank liked to get the most out of their employees for lowest labor costs.
I programmed the device driver for the RL01, I believe, originally for the PDP-8. It used a technology that permitted bad disk blocks, detected during manufacturing, so the device driver maintained a map of the bad blocks to make them disappear from the address space. And all this in 512 12-bit words of memory.
Most people would ask how? Until they understood how well the DEC hardware was made. Everything was done by the hardware. You could write drivers that were tiny...in some cases, 2 words for a bootstrap loader. I have an DEC LSI-11 made by Heathkit. Kind of a rare specimen. with dual RX01 drives.
That's amazing. Testing for bad blocks was necessary for prolonging the disk's usefulness. Sometimes you had a mission critical operation where you couldn't just simply change out disk packs.
@@classicnosh Yes, indeed. My understanding is that the product was successful based on my special formatter and device driver. Of course, today disk technology is far better so the need to support bad blocks or tracks probably is no longer needed.
I assume there also was a diagnostic utility to read marginal sectors and write them to an unused sector and re-map the bad sector to new sector without data loss?
@@JanBruunAndersen Not exactly. You had to retrieve the good data onto another drive or a tape. Then you could run the formatting program, which would start with the factory-determined bad block list then test all the blocks as fast as possible then create the final bad block list mapping and combine it with the code so it would fit into the 512 words allocated for the device driver, which it would then install. Then you'd copy the data back to the disk. If we wanted hot/dynamic bad block elimination, we could not have fit it into the ancient device driver scheme. Our achieved goal of mapping out the bad blocks so they disappeared was the most we could hope for. I'm not actually sure how they set up the RL01 for a PDP-11, since all my code was for the PDP-8. It might have had an all-hardware controller, which would have done the bad block mapping.
We had VAX computers when I was at GE from 1983 to 1991. Also MicroVAX. The disk packs were 3 or 4 times the height of the RL01 as I recall. The operation of the disk drives and status lights brought back very fuzzy memories...
The good old days, the smell of a crashed head on the platter, setting the cats eyes, mod wiring the backplane for the controller to boot the RLO's, (used to love playing with the platter spindle, you could use them for drive shafts on a tank). Going into data rooms that permanantley smelled of the last crash. Also the Megatek Whizzard graphics (I think 7700) controller that was sometimes the graphics controller (used in REDAC systems) connected to a kratos Mono Vector monitor or a mitsubushi colour Raster running Dsys diagnostics. the 11/34 and 24 were the ones I tended to service the most often.
I once had access to a PDP-11/44 running RSTS/E. that was the extent. My first time at college I realized you could allocate devices from terminals things like other terminals etc. including the system console. That's a story in itself. However in my career I also got to manage a Data General Eclipse MV9500 that I upgraded to an MV9600 that was running AOS/VS II.
Nice video... brings back lots of memories. I started RT-11 version3.0b in 1978. I was with DEC FS for Decades. Minor detail, MSDos came after RT-11 so RT did not look like MDDos... it was the other way around.
As a software developer, I had a lot of respect for Field Service engineers, who had to handle just about any problem, sometimes in very short periods of time.
Beautiful. We had an 11/23 with RL-01 (I think) drives at college which I was allowed to boot into RSTS/E in the morning... and this is pure nostalgia for me.
We had two of these in my lab at Washington University in St Louis. One of them was for general scientific programming, and the other was automation for a scanning electron microscope. Each had 64k words of memory. Great machines!
In the late 80's, I had my own complete PDP11/34 system with a VT52 terminal, 4 10MB drives (RL-01) and a full-size tape drive (14" reels). I purchased the system for $350 and 3 of us hauled it home. I don't know what it sold for new except that the tape drive had the original invoice taped to the back showing a price of $65,000! Everything worked and it looked brand new. I played with it a few times, but it didn't really do much. It had the RSTS operating system that included BASIC. The seller gave me a few disk packs and tapes they still had. I found a tape of something called "UserBase" that appeared to add database ability to the system but I never figured it out. What a beast, but I loved it. It took up half my dining room and was louder than a jet plane. All my friends thought I was nuts to buy it, and of course they were right. My IBM PC ran circles around it. So why? Well, I had a job for a while programming a massive PDP11/70 colossus. It was maxed out with dual CPUs, 10 250MB drives (the huge disk packs cost $1200!), and 5 definingly loud "drum printers" -- all in a climate controlled room with backup power and a Halon fire system. There were 63 VT220 user terminals connected and the stack of cables behind the main unit was 2 feet deep. It was such an impressive monster that just starting it up made you feel like a god. I just had to have one of my own. Sorry to say my system eventually ended up at the dump (*sigh*). Much like the 11/70 I worked on. It was eventually hauled away (donning a 'for sale' sign that said 50 cents or best offer) and replaced with a very big VAX system. But that was only used for about 6 months before company politics caused the VAX to be auctioned off and replaced with an IBM system 38 plus new terminals and miles of new "twinaxe" cabling (those IBM salesman are good).
Sigh. Prices were very high in those days. They had to support may trained people to sell, build, and maintain the hardware, and to program the system software. I worked for DEC in several departments, later worked for Prime Computer and lots of other companies.
Thanks so much for posting this! I miss this machine so much. RT-11 SJ had a multitasking cousin called RSX-11, designed and implemented by none other than Dave Cutler, the only intelligent person still left at Microsoft. The KD-11's had TTL ICs on them and was built out of 74LS181's if I recall. I could fix them with a scope and a soldering iron. I wish I had one in my basement. I spent so many hours playing "Advent" on this. Wrote tons of code for the IP-11 too decades ago! Thanks so much!
jeeeeezooz the goony imp steals a wash en 'li-in'2 rich global xmass'uk'repeated'call-en-daa'advent messir lordy buck owns'eer hitlaa hang em hell o yearz ti em c2....
Dave Cutler, Bob Glorioso, me, and a few others tried in vain to influence DEC to make tiny computers. I even made a Basic mockup called Xenon with a big red context-sensitive Help button, and brought in tiny computers like Sinclair for show and tell. If management had listened, there could have been a chance for DEC to survive the microcomputer revolution. But they just love big stuff like VAX and the new Fox architecture that never survived.
I have a piece of dingy green fanfold with a listing of RSTS/E Basic+ StarTrek for the VT52. I can emulate everything, but I don't know of a completely accurate VT52 emulator for Linux.
I used to use RSX11M on a PDP11. It was a newer 80's model. I remember being told that they had a choice between this machine @ $35k or a new thing called a P.C. They decided that P.C.s were never going to catch on and endure so they bought the PDP11! It had a 10MB drive but only 540k RAM. We used it in conjunction with an X-Ray Spectrometer for metallurgical analysis. There I had to issue an MOU command to mount the floppy AND the hard drive. You know in the end I wound up owning that machine myself but I was too young to realize what I had so I got rid of it at some point!
Used to Maintain Dec. A lot of these tpe were used for CAD and graphics Via the Megatek Whizzard Controller. Unplugging the drive number button to change the boot drive. VT terminals especially Vt220 used to blow the serial interface chips like no tomorrow.
My first real computer (as opposed to programmable calculators) was a PDP-11/34 running RT-11 but without a disk pack. You could store anything that would fit on a pair of 8" floppies given the RX-01 floppy pair that was the entire mass storage. Later the school bought an 11/70 which ran RSTS/E.
Vaya, como me acuerdo de estos RL01, eran discos Winchester, se encontraban encerrados en una caja (enclosure cartridge). Algunas veces había que pasar un disco de scratch para comprobar si la cabeza del RL01 había perdido la capacida de lectura o escritura.
Man I want one so bad. I love my J11 Monolithic Ceramic Courtesy of Christian from Play With Junk Channel. He Responded To My Silly 🙃 but Serious Comment and answered my Prayers. God works in Mysterious Ways Indeed.
would be nice to see what it can do in 2020 of course the job it was used back then if its still usable for that or other purposes it can serve well in 2020
Don't hold down the "num lock" or as DEC called it the "Gold" key. Press it and let it go before pressing the second function key (as you did with the "7" key on the keypad). I had hundreds of complaints from users who would hold the Gold key only to have something weird happen when they did. I had one user who constantly had problems who swore she had to keep it pressed who blamed all the malfunctions on her terminal or other non-related issue.
I thought that UNIX would be case sensitive because I find with the OS that I am running on my computer if I use CD or DIR I get the error CD OR DIR not installed do you want to install it but if I do cd or dir then the function operates as expected if you are interested as to what OS I am running well it is DEBIAN UNIX, if I want to edit something I use gedit, I am running Linux Mint 17.3 (Rosa) 64bit (Cinnamon) Lothar Scholz I could run Doom under Wine for Windows and would be very fast, I have had a good close look at a PDP11/34 which was installed at Trostan Avenue which was the Collage of Further and Higher Education, But the DEC VAX750S was brilliant but if you wanted to do something like add extra memory or something than you had to wrap up warm as it was so cold that even brass monkeys would have problems.
That would be really cool to make an RL-01 drive with a USB ibterface so you could run one as a USB thumb drive. ..... Can you run Linux on that thing?
Probably not Linux compatible - 128k is nowhere near enough memory to run even the slimmest kernel, let alone anything else. Plus if it's as similar to the 68000 as is sometimes made out, it might not have sufficient virtualisation and memory protection abilities by default ... though some 68k based workstations got around that by incorporating bespoke memory management units and the like, so possibly if you added that plus a load more memory it can run a very spartan distro, very slowly, and without any graphics. Not sure why you'd want to though. I mean, the default DEC OS (TOPS, I think?) was essentially a thinly disguised Unix fork, so that should do the job in most regards, and that's what all the software will be designed for.
The "computer" is the lower module in the rack; the upper two boxes are the equivalent of a pair of external (and removable-platter) hard drives. So, yeah, the entire system is in that frame, though the terminal used for human interface is of course separate. That's where you get the "minicomputer" vs "mainframe" distinction - a mini would fit into just one of those racks, often only needing a half-height one (or three quarter like the floppy-equipped system next to it; full height if you added a DECtape module, network adapter, etc), whilst a mainframe used several full height boxes, each one dedicated to an individual function, and the terminal alone could be as large as a mini. Whilst "microcomputers" went the other way and compressed everything into a free-standing box (and maybe a second for the data storage) half the size of a typical minicomputer CPU module, or even into something resembling a terminal.
early 80's, most likely. The PDP-11 came out in the 70s, but they were often used up until the 90s, and in some cases up until just a few years ago. I had a friend working at a major semiconductor company that said that they still used these PDP-11s in their labs until just 3 or 4 years ago.
The system architecture is nothing like x86... Also, the point of a PDP-series machine was never gaming, but rather data processing, industrial control, laboratory experiments, etc.
If you installed enough memory into it, and a graphics output or at least a much faster terminal, you'd be surprised. The PDP/11 has about the processing power of a midrange 68000 (indeed, much of the 68k architecture was directly based on it), and whilst there aren't really any official versions of Doom for pure 68k machines (68020s and certainly 68030s, yes), there have been plenty of unofficial ports with varying degrees of faithfulness to the original, and even more good quality Wolfenstein rip-offs. So it might still only manage a couple of frames per second, but it could be attempted, and a Wolf3D clone would likely be fairly playable.
@@TahreyUK Even though the CPU may be powerful enough. There was no direct graphics display. All interaction was via VT type RS232 terminals at fairly low baud rates, so doom wouldn't be possible. Simple maze games with static backgrounds are about the limit.
This thing is quite expensive, they are no longer being produced, and they are some form of an artifact for people who like collecting old hardware and such.
He may have only shown off the very basic functions, but that's not all it can do, same as if you were only shown DATE, ASSIGN, HELP and EDIT on an MSDOS machine you wouldn't think those were its only functions. PDPs were quite a popular choice for all kinds of professional, academic and other institutional uses, and a home user who doesn't really have any call for any of that other than curiosity can still find a good number of games to play on the system as the DEC hackers weren't exactly unfond of computer gaming. As for the noise, they were still a lot quieter (and smaller, and easier on the power budget) than an equivalent mainframe of ten years earlier, and those fans are probably quite worn out with less than smooth bearings these days. Normally you wouldn't work right up next to it anyway, it would at least be in the other corner of the room (serial terminals can use very long cables without any trouble) and maybe behind an acoustic shield or with the fans venting out of the room, or just as likely in an entirely different room altogether and forming the basis of a multi-user system with a dozen or more remote terminals, a lot like the modern day equivalent server room.
Hello this VAX11/34 is very loud! if i would like to bring one home of this my better side will kill me! hahahaha I think i must have one of this but i don't have enoth space anymore for a small Computer lile the VAX11 Best Regards Volker