If you like to give some comments on the site, this is the place! All kind of input is welcome!


I was working on an HP 9845S computer. It was in 1985, in the USSR, in the city of Sverdlovsk, at a scientific institute. The computer was used to control the mass spectrometer. He built mass spectra of various materials. I really liked the computer, at that time there was nothing like it in the country. And the basic language was very convenient and easy to learn. I mastered it in a month. He wrote programs for scientific experiments. A. Smirnoff, Russia


I want to express a huge respect and admiration to guys maintaining this site and info. I love HP vintage computers and I had a privilage to work on some of them. Keep up great work! Kind regards from Slovenia / Europe Stanko


Thanks for very good HPIB-Tutorial. It helps me by troubleshooting HPIB interface of my HP6627A. Krzysztof


Your work has been life saving. I truly appreciate all the hard work you have put into it. People like you sharing software for free is what makes the world what it is today. You deserve a medal sir!


Nice site!

I was hired to do some programming on a 9845 in the early 80s. There was a little hardware glitch in an internal connector somewhere in the machine I was using. So sometimes characters would be jumbled on the screen. Opening the machine and yanking the connectors and PCBs fixed the problem.

One day one of the staff called me. The computer showed garbage on the screen and they knew I had fixed this once before. Could I repair their expensive computer?

I entered the room with the broken computer and several worried people. I walked slowly to the machine and sat in front of it. Then I gave it a decisive blow on the side. The screen was perfect! The people present couldn't believe their eyes and I was the unofficial hardware magician on that company from that day :-). Per Schröder


I think that I was the 1st customer of HP to use two HP9825's in a 192 channel PC to PC to instrument rack SCADA system with CRT. I developed all rpthe user interfaces and hardware with realtime single key code commands on a 1 mile data link at a rocket launch site using hardware DMA and batch datastreams with 1 second closed loop feedback verification even on adjusting each PSU voltage using the numeric keyapad to select PSU 1~9 and then ± key to increment for long umbilical voltage drops. That was around '77~'78 using HPBasic and GPIO and Extended data link drivers (RS485). It had high speed mag tape for auto boot and restore values in the SCADA system and forms mode in the smart remote CRT for inverse video cells like a spreadsheet to display all the values and experiment states for in or out of tolerance and flashing if critical with all normal font prior to launch. (This was before SCADA was invented or even "thought of" to my knowledge. Tony Sunnysky (tony.sunnysky (at)


Searching around looking for some info on the hpib interface and I found your site. I have a couple of old HP1000 minicomputers with a 7900 disk drive. I'd like to boot up, but having experienced a few head-crashes with these 40 years ago I knew I'd be living on borrowed time even if the 7900 came up initially. I'd been musing the idea of building a disk emulator on a PC and linking it to the HP1000 using HPIB. I had done some assembly language development years ago interfacing HP 7970E tape drives to a PC with the National Instruments IEEE-488 card. SO - here I am, amazed that you have already done the heavy lifting for me!! Your HPdrive emulator is perfect for what I want to do. I'm putting together a PC to try it out along with the HPdir and fido programs. Thanks Ansgar! (PS nothing wrong with your English in the slightest!) - Ken Smyth Maryland USA


Never knew there was a San Diego Division but seem to remember that Neeley Enterprises was somehow closely linked to HP.

I was an analog and RF guy at several companies in San Diego from 1958 until retiring for good around 2000. Along the way I found myself managing a group which was incorporating microprocessor chips into our tracking systems so I decided to learn something about computers. Since we had several HP desktop "computers" and plotters I bought a Commodore PET because it had an HPIB port. I was able to become a fairly good programmer and laughed at the fact that my $600 computer was driving an (approximately) $3,000 plotter.

In 1957-58 I worked in North Hollywood for Bendix Pacific and used several HP instruments to test a PDM Telemetry Keyer, getting a patent on a very linear transistorized ramp generator. Just out of the Navy, I started that job by buying a book on transistors. That's how things were done in those transition days.

Over the years I have gone, personally, from an HP 45 on up to 200LX which I still use on a daily basis. (I had to upgrade from a 100LX to a 200LX because the serial interface on the 100LX couldn't handle the speeds needed for data collection when I went out to collect medical office data for conversion to new software. I ended up working with an HP engineer overseas, maybe Singapore, who told me there was no fix for the 100LX port.)

And yes, I did use the very first HP sine wave generator. I remember it had a light bulb, or something similar, to control the output level. The output level did change as you moved the frequency dial, but stabilized after a second or two.

It is probably due to HP that I started my own computer systems house in San Diego.

Anyhow, HP was a superb company, admired by everyone . . . the standard!

Don Williams Retired back in Oklahoma


A follow-up to my own comment and a "shout out" to Bob Myers. The individual who probably knows more about early HP Desktop Computer division displays than anyone. I predate Bob at HP, having started in 1972 when the HP 9830 Basic Language Desktop Computer had just hit the market. I worked on the proprietary chip set that was at the heart of the hp9845 computer capability. I also worked on all of the HP Workstation display subsystems that went into the HP98xx, HP300 (Motorola processor) and HP700 (PA-RISC) systems. Regards, and thanks to the website for a trip down memory lane. Dan Griffin (dgriffin (at)


Wow, what a great site to stumble across! I started my career at HP as a components engineer at the Ft. Collins site - the "Desktop Computer Division" - in the summer of 1979, when the 9845A was in production and we were all working on getting the new versions, with the 98770A and 98780A "tops," wrapped up. Among my responsibilities at the time were CRTs, deflection yokes, and other magnetics, so I was thrown right into it what with the new color tube, and what was probably among the most complicated set of neck magnetics, convergence circuits, etc., ever put into a CRT display. There were some very brilliant design work done on these things, and it was a privilege as a new engineer to be able to watch it all come together. If any of the old HP crowd happen to see this, please drop me a note: bobmyersco (at) gmail dot com. - Bob Myers, formerly of HP DCD/FSD/WSD/GHL/and so forth...


Would anyone like an HP 9836 based Shared Resource Manager (SRM) system. I have one that was removed from service (working) in 1996. Fascinating that anyone would work so hard to preserve information on a product that I helped to design. Regards, Dan Griffin (dgriffin (at)


Great to see all this old info. I worked on projects related to the 9835 as an HP summer intern in 1979 in Fort Collins and then spent the summer/fall of 1980 there working on other projects. When I went back to HP in Fort Collins as my first job in 1981, I was the design engineer for the 12" monochrome monitor of the 9836. The basic electronic design was based on the display of the 2621(?) terminal which was designed by George Crow, who left HP and went to Apple to be the analog design guy for the Mac. I learned a lot doing that project! Bruce Young (bruce (at)


My name is Larry Brunetti. I was the project manager on the 9872 project. It was to replace the 9862, but with much more capability: it could draw characters and make multi-color plots with a programmable pen changer. The product was originally started in Loveland and was transferred to San Diego Division. The design was dubious, because the design engineer in charge thought that stepper motors were the way to drive the x and y axes. He was a "self-proclaimed expert" in stepper motors. The design ended up being driven by the BPC, the same processor as in the 9825. The stepper motors ended up being driven by, essentially, two-phase digitally generated sine waves and had encoders on their shafts. The cost was out of sight. The Loveland people decided they would not support the plotter since it would sell for over 2X of the 9862. They decided to support only a CalComp plotter and had the driver in a ROM drawer. We ended up using the Command prompt on HPIB to write a two letter mnemonic interface language to the plotter: HPGL. The descision to NOT support this product led to the invention of HPGL. This one product took the San Diego division from a sleepy $30M per year to over $400M.

I worked at the Colorado Springs Division and at the San Diego division. While at the Springs, I met Colin Cantwell, a consultant on many movies. He had a need for a very high resolution display, with a white phosphor. It was to be driven by the 9845, and was used to program all of the large screen graphis for the movie WarGames. I worked with Colin and the People at the Springs to package a number of systems that were delivered to Hollywood for the movie. The high resolution display was used for medical imaging. The HPIB interface was developed by Arnot Ellesworth. The display and white phosphor was designed by XXXX Carnahan. Larry Brunetti (tuku (at)


Great site and collection of data. My first project when I went to work at HP was the 9845A I/O ROM. Many projects since, but this will always hold a special place for me. Jay Nemeth-Johannes


Hi Ansgar, Thank you for all the info and your work on this and other HP computers and interfaces, it is a mammoth effort and you are as mentioned above by others a genius in this field! I am hoping as your most recent guest Marc to get my HP85 doing some control work on our farm .All the Best for your future efforts! Cheers Suz (suerhett (at)


You are a genius, and your HPDrive utility works like a charm using a HP-85 and a NI PCI-HPIB TN5404 based card. I installed the custom driver for the card, then emulated a 92808 unit on the PC: HPDRIVE -82901 diskimage.hpi (I used on of the LIF disk images that came with Everett Kaser emulator Then I just connected the HP-85 to the HP-IB card. On the HP-85 I did: CAT ":D700" and voila, all the files available to LOAD on the HP-85 or COPY to a tape, or to STORE back on the disk image. Fantastic work! And hard to make it simpler to use. I have just purchased a real 82901, can't wait to see if it works equally well with your HPdir. Marc


I believe my horse is hopping. Since many years 2 fat 9845t are stalling in my photo darkroom, including spare parts and documentation. never thought that people would work with those computers in newer time. I worked with the system45 over 15 years. From 1976 until 1997. Next year when I will be retired I'll check for functionality of my parts. regards Fokke Oosterhoff


In 1986 HP1000 was my first deal and still is in 2012 as an HMI and production management system in a line of rugged German Schwabenland (Southern Bavaria) web printing presses. With this kind of user devotion it is like restoring classic cars. Shall I give it a shot? I have no fear and lots of guts. My beloved HP1631D Logic box needs an PC interface as well beside my 5 HP1k-600-400 and 2 HP9k-300 with a ton of HDD's. What is the HP1k support size please? I would love to join the crazy HP1k / 9k gang. (doc-hecky (at)


My first machine as a professional software developer. Like Karsten, I wrote CAD applications on the thing. The digitizer and D-size pen plotter were wonderful toys to play with. The external hard disk drive was so loud, we put cubicle wall panels around it to deaden the noise. People think I'm nuts when I tell them that my first job was programming in a mix of Basic and Assembler! I've carried many lessons from those first five years through to this day. I visited the old place in the early 90's, about 6 or 7 years after I'd left. The 9845 was still chugging away and they were still using the programs that I wrote for it.


Congratulations to this fantastic work ! It's wonderful to see the machines of the beginning of my career as CAD developer. Yes, CAD on computers with a few 100s kB of RAM... unbelievable today. They were fanatastic and better than everything else available at that time. And despite the high prices (some said this was the real meaning of "HP" ) they were the only affordable systems for engineering offices (compared e.g. to a VAX and Tektronix graphics terminals). In 1979 I had a programming training on a 9835, and half a year later our first 9845T came along with internal thermo printer, 2 tape drives, 98034 HP-IB Interface, 98041 Disk Interface, 9872B Plotter, 7906 M Disk System (as loud as a startig jet...), 9895A dual Floppy and 9874A Digitizer. Later we got a 7580 "Berta" and 9111 tablets, 82906 printer and, of course, the 9845C with light pen. Then we switched to the 200 Series (9836C, 9920, 216, 217, SRM-System, 7585,...). I have some additional infos to the 9111 tablets : There was a 9111T model. As far as I remember, this version had an additional operation mode : stream data. The coordinates were reported continuously. On the 9111A they always had to be acquired. Best Regards, Karsten Lengwenus.


Great site. In 1979, my father leased the 9845B from HP for use in his machine shop. I went out to Colorado for training. I came across some of the old 9845 manuals that I used. Bryan Cope.


Thanks to all involved in this tribute to the HP 9845 desktop computer. I actually have one of the original posters of the HP 9845C framed on my office wall. More importantly, I literally owe my professional career to the HP 9845B as I started in 1979 as a "Programmer Analyst" at Rockwell International's Space Transportation and Systems Division in Downey, California. Rockwell International was absorbed by Boeing and the Downey site was closed. In April 1979, I was hired by Rockwell International (RI) during my first year of college because I knew how to develop code in the BASIC programming language. Actually, I had only taken a single class in BASIC the year before in high school and the class didn't even have a single computer. However, none of the engineers in the (Space Shuttle) Flight Systems Design and Performance department were interested in the HP 9845B because a) it wasn't a mainframe; and, b) it didn't run FORTRAN. However, I eventually wrote a suite of programs for the HP 9845B to support space shuttle launches from STS-2 through STS-24! This is a long story in and of itself and I'll be glad to share it for those who may be interested. David Waters (hello (at)


Cool website! I was one of the first users of a 9845A in Germany. We used it as an instrument controller in the RF Lab at the University Of Applied Sciences in Cologne. If I remember right, it cost ~ 80kDM (today 40k€) and was the most powerful computer at this time at this site. Best regards, Peter WR.


Many thanks for this nice piece of SW.I am using an old HP network analyzer 8753B. This machine (and others from the same series) use a HPIB drive like the HP9122 for calibration data and settings. These drives are hard to find.... The hpdrive utility worked flawless with an old National GPIB- ISA card on W98. Radio amateurs like me are starting to use this equipment because it becomes affordable now. With HPdrive I can make full use of its capabilities. Kind Regards, Rob Krijgsman.


The HP 9845 was not the first of a series of workstations, it is at least the third, there being a 9810, 9820, and I believe a 9800 proceding it. I did significant computing on the 9820 and some on the 9800, if that were the model I first used. Larry Stringer, Lockheed retiree (lstringe (at)


Oh my!! Just stumbled onto this looking for something else ... what a great time working on the 9845A B and C! Good times, good friends, so many smart people in one place! Bob Jewett (Bob_Jewett (at)


I don't think I've ever seen in one place such an impressive combination of expertise in hardware, programming, and documentation; my sincere compliments to Mr. Kückes. Our lab is well stocked with state of the art instrumentation -- but we also have a 9845 that is still used for data acquisition. It's a hard system to beat. Tom LeBrun, NIST.


I worked in the R&D lab on the 9845 in Loveland for Jack Walden on the PPU firmware. I had also worked on the 9100 and 9830 computers. I feel very lucky to have worked on these exciting products. We had no idea what the PC market would become and that HP would eventually be the leader in PC sales, for now anyhow. I am retired and enjoyed this site. Thanks to the developers. Frank Cada, Loveland (cadabase-1 (at)


This is a fantasic website, I am glad to see so many others appreciate the '45 as much as I did and still do. My bitslice unit, which I bought new in 1982, was the most reliable and productive single piece of equipment I ever purchased, running 8-10 hours a day, 6 days a week, until 1996, without a single moment of downtime. And it still works fine today, though it's only powered up a couple times a month now. With so many thousands of hours spent writing in Basic and Assembler for it (never did figure out how to make binaries), I can't afford to give it up, though I've ported the most frequently used ones to HTBasic. Best wishes - John Bau, Ex designer for Spica (jbau (at)


A trip down memory lane, I used the 9845's from the mid 70's through to the mid-late 80's in the offshore oil exploration industry (seismic). I fell in love with them & would still like to own one. They were so easy to work with, debugging software was a cinch, writing "on the fly" specialized software was also a cinch, even with massive array data sets. We typically had 3 on a vessel, 2 in use - 1 spare. Due to the modular construction, trouble shooting was no problem, a fault could be traced to a particular module by inter-swapping & only a faulty module replacement ordered - not sending the complete unit back to a shore based service centre. We used these machines in a harsh marine enviroment & they were surprisingly robust. I personally repaired 2 units that had been in a ship's wheelhouse that had been hit by a giant wave - bridge flooded. Both units were re-stored by simply stripping down, cleaning & reassembling. I still have program listings (HP Advanced Basic) of the software we used, the complexity & functionality of which would daunt a modern programmer, where memory space is not an issue.

Best regards - John Thierjung Ex Western Geophysical employee (jthier13 (at)


Talk about a blast from the past..... The 9845 was my 1st encounter with a desktop..... I was a SSgt at Headquarters USMC... had some cool bosses that sort of had a "go with it attitude".... There was this thing over in the corner under this dust covered tan-brown cloth cover....... I was curious........ Bossman LtCol Frank Soderstrom told me if I could get it to do anything everyone would be amazed....... w/in a week or so of lunch hours & a bit of after hours investigation.... this 'lil beauty was the envy of the entire hallway....... The 4 pen plotter became the gee-whiz momma of HQMC manpower briefings..... people were fighting for access time........ This was well before the IBM PC........ Good memories.... Retired as a Master Sgt....... Semper Fi Z (cas.z (at)


Fun site. Wish the pix were better populated. Used (and wrote applicatons for) the 9845 (and 25) extensively back in the early '80s. The things were almost bullet-proof and we wrote all our own apps. I'll try to write up a blurb describing what we did with the 9845's way back when.

choelzer2 (at)


Fantastic site. Full of hard to find technical informations. Ansgar, with his great knowledge of the 9845, help me revive my machines on more than one occasion. The hpdrive utility is also very useful. Thank you.

François Lanciault


I'm pleased to see that somebody finds my schematics useful. It makes the hours (weeks!) of staring at PCBs well worthwhile :-)



Two days ago, I got a working HP 9845B and lots of documentation. Together with the comprehensive information on your site I'm sure I will have much fun using this marvelous machine. Thank you much for your excellent work! Best Regards from Switzerland, Jürgen Keller


Ansgar, This is some of the best work I have ever seen! Well done. The 9845 is a classic, but very complex and tricky old beast. Your site will go a long way to helping the rest of us preserve these old beauties. Thanks for all the hard work. Cheers, Jon Johnston (


Nice site!


Congratulations for the HP 9845 project! For years I searched the web for in-deep information about this dream-computer, but even the museum of hp calculators does not have much info about it. I definitely will re-visit this site often and see what you have achieved. Good luck with it!

I have got some copies (color copies of color pages) of the HP Journal issues describing the HP 9845 and HP 9845C, if that is of any interest.

Best Regards,
Stefan Falk


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