Ask HN: Who's still keeping a DOS machine up because the business depends on it?

Do you currently work with or know anyone who is still using:

* dBase/Clipper/CLARION/Paradox/other DOS RAD environments on period hardware to run business processes?

* CNC mills/spectrometers/microscopes/other industrial instruments controlled by ISA cards (either bespoke or standards like GPIB)?

* Anything with a parallel port dongle?

If so, I'd be very interested in hearing your experience here, or feel free to send me an email at the address in my profile. I'm not trying to sell anything, just doing some research for an idea around keeping these going on modern hardware.

135 points | by mlaux 15 hours ago

53 comments

  • freeli 12 hours ago
    A certain nuclear power plant had a Windows NT 4.0 machine running as late as 2007. The reason is interesting.

    The machine's purpose was to report status of the control rods that mitigate nuclear reactions. Basically, "are the rods inserted, and if so, how many / how far?". I want to emphasize that this was reporting only, NOT control.

    The original software was written back in the 80's, when the plant was originally commissioned, for AmigaOS. Of course, it's hard to buy Amigas anymore, and the original one died long ago (nobody remembers when).

    So in the mid '90s, the utility purchased an AmigaOS emulator that ran on Windows NT 4.0, which was current at the time. The emulator (IIRC) was developed by a firm in the UK. The firm went out of business sometime in the late '90s. The control rod monitoring software ran under this emulator on top of NT4.

    Windows NT 4.0 was the last OS to allow the emulation software direct access to the physical hardware that produced the status signal. Later versions of Windows abstracted the hardware access away, and the monitoring software broke. Because the emulation company had gone belly up, there was no way to fix the incompatibility.

    So the utility had a choice: get new hardware/software certified (by NRC?), or keep doing what they were doing with the software (and hardware) that they had. They chose the latter.

    So this is how, in 2007, during a tour of the facility, I stumbled across a Pentium 1 system running an AmigaOS emulator on Windows NT 4.0 that was responsible for displaying the status of the control rods of a nuclear power plant.

    Spare hardware for this setup was purchased off of eBay and stocked on an adjacent shelf.

    • throwaway2037 36 minutes ago
      This is a great post. How does someone write software that needs to run for ~50 years where the hardware will need to be replaced with non-equivalent, newer hardware? If I were facing this issue today, I might start with an OS that has excellent emulation. Example: Can I run 32-bit MS Windows 95 via emulation on a variety of current 64-bit OSes, like MS Windows, Linux, AIX, HP-UX, etc. If yes, then we can assume(?) this emulation will remain relatively stable even if we upgrade our hardware later. Maybe I am overthinking the whole problem: Can VMs do exactly what I want today? Will VMs running ancient OSes, such as 32-bit MS Windows 95, continue to be stable/viable in the future? I am unsure.
      • dmos62 2 minutes ago
        > how does someone write software that needs to run for ~50 years where the hardware will need to be replaced with non-equivalent, newer hardware?

        Make it open-source, or don't buy without source.

    • CobaltFire 12 hours ago
      Having worked on nuclear plants (as a reactor operator) around that time this doesn't surprise me in the least.

      Thats far more advanced than the systems I worked with, one of which reported rod position via resistance measurement on a brushed cylinder (one for angular and one for depth).

      Cleaning and calibrating those was a constant maintenance item every time the reactor was shut down.

    • Froedlich 10 hours ago
      A friend works for an airline as a flight simulator tech. Their entire software stack, including the compiler and OS, is FAA-certified.

      Then their ancient Honeywell(?) mainframes reached end-of-life they scouted for compatible hardware, of which there was none. The cost of certifying new software, plus the time involved, was astronomical. So, after consulting with the FAA, they paid a hardware company to clone the ancient mainframes in modern silicon. The FAA signed off on it, and they had all-new computers - much smaller than the originals - running the old stack.

      • zx8080 10 hours ago
        It's _very_ hard to believe some company to simply "clone the mainframe" into chip. Mind sharing any link to this effort?
        • mitxela 46 minutes ago
          Custom chips aren't as expensive as you think. About a few million dollars for the design and a hundred thousand chips, way out of reach for a hobbyist, but accessible to large enough companies. Just because it's opaque to us software people doesn't mean it's not a real industry you can buy things from.
        • vincent-manis 9 hours ago
          When Xerox established PARC, they asked the assembled scientists what computer they wanted. The majority view was a DEC PDP-10 KA10, with the BBN memory management unit that let it run Tenex (the ancestor of DEC TOPS-20). Xerox couldn't really buy a competitor's mainframe, so they built MAXC (maximum access computer), which was a complete emulation of the Tenex machines.
          • zem 1 hour ago
            very apt that xerox parc was full of tenex engineers!
        • znpy 1 hour ago
          Meh, old architectures are relatively simple and you can get 95% of those via fpga softcores (some freely available, some paid) and run them on fpga. The rest can be implemented by a proper ee team.
        • theodric 1 hour ago
          I mean...there's some precedent. The XKL TOAD ("Ten On A Desk") implements the PDP-10 instruction set, and will happily run TOPS-10/TOPS-20. LCM had one doing just that.

          https://www.computerhistory.org/collections/catalog/10277383... https://www.twenex.org/?network

      • betaby 10 hours ago
        That's interesting. That means there are fewer checks for hardware than software?
        • hulitu 2 hours ago
          Software "engineers" like to abstract things. This doesn't pay well e with reliability.
        • soulofmischief 10 hours ago
          Hardware is more amenable to static analysis than running programs which may receive an arbitrary number of inputs and express an arbitrary number of possible intermediate states.

          I am interested in how firmware is treated, since perhaps in the case of these old machines it's small enough to be analyzable or at least cloned bit-for-bit.

    • sajithdilshan 2 hours ago
      This is crazy. Why on earth wouldn’t the respective government spend money to modernize a critical infrastructure like a nuclear power plant?

      This is how we would end up with nuclear disasters, not because the technology is bad, but purely because of mismanagement and human negligence.

      • IG_Semmelweiss 3 minutes ago
        Lindy's law:

        For non-perishable things - i.e technologies, ideas, books, institutions - the expected remaining lifespan is roughly proportional to how long they have already survived

        Time acts as a filter: what has already withstood a long stretch of disorder is more robust, so the longer it lasts, the longer it is expected to last.

        The old nuclear software running on mainframes have passed the test of time. The new software, has yet to.

        Nassim Taleb talks about this at length in his book, Antifragile.

      • onion2k 2 hours ago
        This is crazy. Why on earth wouldn’t the respective government spend money to modernize a critical infrastructure like a nuclear power plant?

        Safety and reliability come from understanding the system. Something that's old but that you know everything about is far safer than something new. This risk is that the people who know move on, or the sources of replacement parts stop working, or that other things around the system change. Then the risk curve inverts and you find the old system more of a liability than a asset.

        Almost always people choose to update things either too early or too late. Knowing when to do something is hard.

        • sajithdilshan 46 minutes ago
          That’s pure negligence. It’s not like the people that have the know how disappear suddenly . It’s the responsibility of the management to make sure the knowledge transferred to new generation.

          I guess that kind of thinking is what led to the collapse of ancient civilisations like why even bother to improve anything and let everything decay and die out

      • philipallstar 5 minutes ago
        > This is how we would end up with nuclear disasters, not because the technology is bad, but purely because of mismanagement and human negligence.

        I'm pretty sure constant upgrading would be more likely to cause disasters.

      • cromka 1 hour ago
        If it's not broken, don't fix it.

        Same reason why MTA in NYC still operates subway using 100 y/o signaling hardware on most of the lines.

        In a way, your comment and the responses you get is a perfect allegory to inexperienced vs experienced engineering.

        • mitxela 40 minutes ago
          Their 100 y/o hardware is built from stuff that's still produced though. We still make relays (not identical ones but ones that perform the same function), wires, and mechanical levers. The system's behavior is not encoded in the relays but in the connections between them. If you had a CPU made of separate transistors you could replace burned out transistors with any future transistors but if you had one made of chips you'd need those exact chips that were out of production.

          Replacing the relays in old telephone switches is a problem because they use so many weirdly specific types of relays - but those systems are only found in museums now. I believe track control uses fairly ordinary DPDT, etc., relay designs.

        • sajithdilshan 48 minutes ago
          > If it's not broken, don't fix it.

          I understand that way of thinking for a small business computer system. Not for a critical infrastructure. Also if people actually thought about like that we would still be in stone age, like why invent something new or use a new technology? Keep on using rocks to crack nuts and kill animals

          • sokoloff 29 minutes ago
            I think you can imagine the difference between “I did some work and made this thing that is clearly better, but we might have a few kinks to work out” and “I did some work, and if I did it perfectly, it’s just as good as the old thing, but we might have a few kinks to work out.”
      • mitxela 44 minutes ago
        Now you know why "nuclear power may have been dangerous in the past, but with modern technology it's completely safe and Chernobyl will never happen again" is not a good argument.
        • idiotsecant 33 minutes ago
          Now you know why making arguments from 20 year old anecdata makes you look foolish
      • cube00 1 hour ago
        > Why on earth wouldn’t the respective government spend money to modernize a critical infrastructure like a nuclear power plant?

        Same reason they don't modernize health care infrastructure. It's too expensive, people die if they get it wrong and they get voted out of office for their troubles.

    • kccqzy 12 hours ago
      Did they not need NRC recertification when they moved from a physical machine running AmigaOS to an AmigaOS emulator?
      • freeli 12 hours ago
        That is an advanced question best asked of the folks in charge of the plant. At the time I was just trying to figure out how to explain to the IT auditors why there was no antivirus software on this piece of crap.
        • CursedSilicon 10 hours ago
          Could you skirt around it and just remark "there are no viruses for AmigaOS"

          (Probably not literally true. But functionally true in the sense that they were likely transmitted via infected floppy disks, of which there'd be virtually none left in the wild in 2007)

          • kamma4434 6 minutes ago
            Hello, my name is Lamer Exterminator, pleased to make your acquaintance.

            https://en.wikipedia.org/wiki/Lamer_Exterminator

          • freeli 9 hours ago
            It wasn't the AmigaOS running in the emulator that they were worried about, it was the Windows system running the emulator. (Not that the average IT auditor there could have understood the difference.)
            • M95D 6 hours ago
              How would a virus get in there?
              • EvanAnderson 2 hours ago
                If it were a newer version of NT I'd be concerned about USB media, but being NT 4.0 and not supporting USB it's imminently more capable of being air-gapped than later versions. (I recall a fun Ed Skoudis quote-- "At best, an air gap is a high-latency connection". Evidence Stuxnet.)
              • jabl 2 hours ago
                The auditor probably doesn't know nor care. "Every windows machine runs antivirus" is a checkbox item, zero thought involved.
    • slicktux 7 hours ago
      Was this status indicator simple vertical bars that were black and white and displayed on an old CRT Monitor? Almost looks like black and white terminal vertical bars (like Alsamixer)?
    • icedchai 12 hours ago
      I'm curious, how did the hardware present itself? It couldn't have been an Amiga Zorro card since it would've been impossible to get that into a PC. Did it connect over a serial or parallel port?
      • freeli 11 hours ago
        I recall it being some custom ISA card with connectors on the back. The emulation software had drivers that interfaced directly with the card.
        • icedchai 11 hours ago
          Interesting! So they were able to port the hardware but not the software for whatever reason?
          • ErroneousBosh 2 hours ago
            If it's what I suspect it might be, it was probably a generic IO card with maybe a bunch of 8255 PIOs on.
    • ikidd 11 hours ago
      NT4.0 in 2007? That wasn't even very late. I was replacing NT4 servers into the early 10s. Car dealerships were terrible for keeping that crap around.
    • DoctorDabadedoo 11 hours ago
      I wonder if there is push in the public sector for open source software/hardware for cases like this.

      I completely get the decisions over time here, but it's unsettling having a relevant piece of software (reports are important too!) working on with parts from ebay, in 50 years time they might be gone.

      • NegativeK 9 hours ago
        I've dreamt of governments hiring devs with promises of full time OSS work. It _might_ get some people over the lower salaries of government work. But I overheard a state CIO once say "We configure, we don't create".

        That's to say nothing about opinions of open source that rival early 2000s Microsoft.

        For old ass critical software and hardware, the org can always have a backlog of hardware and contingency plans (paying someone to fix the hardware, paying someone to create a fully certified and modern solution..) for when they start running out of parts.

    • gerdesj 12 hours ago
      "Windows NT 4.0 machine running as late as 2007"

      lol. I know a ... factory, that had a BBC model B (with a rather complicated wiring loom) still doing a job around that time.

      The IT supplier at the same factory went to a museum in Cambs. around late '90s, early '00s to ask if they could buy an exhibit because something had failed locally. The museum gave them the part.

      That was just aerospace and nothing fancy like your nuke plant!

    • tombert 6 hours ago
      I find it deeply upsetting that anything important for a nuclear power plant is using an OS without protected memory.
      • M95D 6 hours ago
        Protected against what?
        • tombert 6 hours ago
          Just another program poking memory it’s not supposed to. Not even necessarily maliciously.
          • JdeBP 5 hours ago
            That AmigaDOS emulation will almost certainly never run another program. (-:

            Far more concerning from a RISKS point of view is the spare parts being physically in the same place as the live machine.

    • vincent-manis 9 hours ago
      This reminds me of the apocryphal story of the IBM System/360 running a 1410 emulator that ran an IBM 705 simulator that ran a business-critical application.
      • JdeBP 5 hours ago
        Not wholly apocryphal. The U.K.'s air traffic control ran, and possibly still is running, on an IBM 4381 substituting for an IBM 9020.

        * https://news.ycombinator.com/item?id=49763972

        They've reportedly already tried, and failed, to replace it with a more modern system.

      • genxy 6 hours ago
        Which is why we should target VMs directly. Then that VM can be brought forward to new platforms rather than emulating the entire machine, not that emulating the entire machine is bad. One could argue that the emulation stack you outline was made possible by putting in the work to make simple, fully specified and documented hardware.
    • ptek 6 hours ago
      If it's still running I wonder what they are going to do about the year 2038.
      • mitxela 39 minutes ago
        Set the date back to 1980 and sticky tape over the corner of the screen where the date is displayed.
    • TMWNN 11 hours ago
      >So this is how, in 2007, during a tour of the facility, I stumbled across a Pentium 1 system running an AmigaOS emulator on Windows NT 4.0 that was responsible for displaying the status of the control rods of a nuclear power plant.

      Vernor Vinge's A Deepness in the Sky depicts a human society thousands of years in the future, in which pretty much all software has already been written; it's just a matter of finding it. So programmer-archaeologists search archives and run code on emulators in emulators in emulators as far back as needed. <https://web.archive.org/web/20231114211656/http://www.gareth...>

      (Heck, recently I migrated a VM to its third hypervisor. It began as a physical machine a quarter century ago.)

  • rleigh 1 hour ago
    Not any longer. Back in the mid-2000s the company I worked for sold point-of-sale systems based upon a multi-user 4GL application (TAS Pro). Similar to dBase/Clipper etc., using the Novell Btrieve ISAM database engine.

    With the advent of USB and SATA we ceased to be able to source industrial embedded x86 boards which could run the application. At the time this was with Novell DR-DOS, which was relatively modern in terms of hardware support but still behind the times and we were struggling to manufacture new systems. The company was very small, so a full rewrite was investigated--I did a prototype using PostgreSQL and Gtkmm--but it wasn't realistic. Today, an AI could probably do a full rewrite in a day or two, including migration tooling. Back then, it would have been a multi-year effort for one person given the application's size and complexity.

    My solution was to run Linux since it had full support for the hardware. Debian Sarge at the time. This used a Perl frontend and dialog(1) to present a simple menu system at startup. This did backups, software updates (over dialup!), remote access for support (again over dialup), ran backups and ran the main application. It would start DOSEMU which provided the application with VGA display, COM ports and parallel ports for the application to drive "directly" (from its perspective). It also used Samba and CUPS to provide the DOS environment with shared network drives with exclusive byte-range file locking needed for the multi-user network database to work with concurrent users without data corruption, and also multi-user report printing and receipt printing.

    I left the company a year after this was put into full production, but the last I heard it kept the company viable with a supportable product for many years after until its owners retired. This kept software from the early 1990s running well into the 2010s, and there are likely still sites running it to this day.

  • pumplekin 1 hour ago
    Not DOS, but two similar era cases.

    A FTSE 100 company I used to work for, still maintains a SCO UNIX machine that was first installed in 1993. It hasn't had any upgrades since, has specialist hardware in it, and still has an IP stack that is classful (ie. no subnet masks, 10.x.x.x is always a /8). It runs in a 100% airgapped network, and it isn't essential to keeping the core companies operations, but it is a ticking time bomb nobody seems to want to address that will cause a lot of distruption when it finally dies.

    Also I was recently (very lightly) involved in a consultancy project to remove an OS/2 based point of sale system for a small local retailer with 6 stores.

    • adithyassekhar 59 minutes ago
      If you don’t mind me asking, how can a thing that causes disruption when it dies still not be considered essential?
  • Aldipower 28 minutes ago
    The Detusche Bahn still runs DOS and Window 3.11 in there ICE I trains! They looked for admins 2 years ago. https://www.tomshardware.com/software/windows/ms-dos-and-win...
    • tefkah 17 minutes ago
      i don’t want to say this explains things, but i do want to imply it
  • shakna 12 hours ago
    dBase, MS-DOS 3.x, not using industrial anything. And as its a front of house tally machine, there's literally zero incentive to ever upgrade it. Downtime is measured in the yearly reboot, but there are non-operational business hours, so everything is just scheduled around that.

    We've already got it running on modern hardware. It's running under qemu. And the dBase stuff gets ripped out and sent to a REST server for broad monitoring and so on.

    We... Have one small oddity? There's a tape backup system, that throws everything through the soundcard. (Sound Blaster only.)

    Would be nice if onboarders didn't see dBase and just throw everything at AI instead of actually learning the skills they'll need when data migrations happen. But that's a people problem that can't be solved with tech.

  • Felger 12 hours ago
    Not DOS, but I sold a '99 HP computer running win98 last month, to replace an identical failed system. It was used to control a 50 meters long custom industrial paint booth line for special equipments (like 57" rims). Luckily, their HDD was OK. Urged them to make a few sector-to-sector copies of it on a few spare HDD. This $100 sell surely has prevented this business from massive bills or even going bankrupt in the meantime from production loss.
    • adithyassekhar 58 minutes ago
      Think that’d be worth more than 100 :)
  • amelius 32 minutes ago
    I bet most AI is capable enough now to migrate you away to some emulator for a few dollars.

    And I would even bet that in most cases you could run a solution on a sub $10 board from aliexpress.

  • ChrisMarshallNY 1 hour ago
    I did, for a while. Then, I used VMs. I haven't had a Windows VM for years.

    If I were a serious gamer (I'm not), then I'd get a hardware rig, but otherwise, I've not needed it.

    I had a doctor that kept an original NT machine, for many years, because his bespoke app worked on it.

  • MarkSweep 12 hours ago
    A company I used to work at still ships a piece of hardware with an Intel 186 microcontroller in it. The compilers are 16-bit DOS applications and the tool to program the DIP packages with the program was also a DOS application. I’m not sure what the physical interface between the programmer and computer was.
  • dazhbog 2 hours ago
    I run 2 old Juki pick and place machines. They run DOS 6.22 on a 486 I think. My biggest pain points are, 1) booting them up without errors, and 2) transferring files to them wirelessly without any floppies. (without installing any DOS software)

    Closest I got was with a GOTEK and an ESP32 emulating a USB. But it was flaky so I dropped it for now.

  • londons_explore 12 hours ago
    This thread reminds me that there is a huge benefit to using a super common OS+hardware.

    In 30 years time it will all be outdated... But emulators will exist and a business process in 2050 that still depended on something I built today could still run with minimal effort or risk.

    • chr15m 10 hours ago
      If you have the source code it's going to be a lot easier to continue.
      • hulitu 1 hour ago
        It depends on the gcc/llvm version.
  • andix 12 hours ago
    I had to keep an old clipper/dbase application running until recently. It worked perfectly seamless with vdos (vdos.info). It's commercial software, but very reasonably priced. Dosbox is another alternative, but didn't work as well with printing and I think also wasn't able to do row locking of dBASE databases over the network.
  • _trampeltier 10 hours ago
    Siemens Field PG. It is a rugged Notebook for PLC programmers. At least in the last version until last year, the "Field PG M6" was possible to buy the Notebook with a special serial port for old S5 PLCs ant the Step5 software came in a special DosBox version with it.

    The Field PG has also another special port called "MPI/Profibus" for S7 PLCs, 2 Ethernet ports and a DVD drive.

    https://support.industry.siemens.com/cs/document/109766662/d...

  • fires10 10 hours ago
    I work at a multi billion dollar facility for a Fortune 100 company and we still depend on DOS. Keeping the mandatory DOS machines going is an exercise. Especially integrating them into modern systems.

    Edit: There is no required hardware, however maintaining a stable serial connection through a VM and timing issues due to faster hardware has been fun.

    • mlaux 10 hours ago
      The serial port stuff is very close to what I'm working on - what's on the other end of the connection? What does "integrating them into modern systems" look like for you: getting data out/pushing data in/both?
      • fires10 10 hours ago
        We typically integrate them by encapsulation. Building multiple layers of more modern systems for them to communicate through. A combination of Windows and Linux boxes. The other end of the connection is very old industrial equipment. This is not to run the equipment per se but to configure and program it.
    • 1over137 10 hours ago
      Actual MS-DOS or FreeDOS?
      • fires10 10 hours ago
        MS-DOS or Windows 2003 running DOS vdm.
  • Sleaker 11 hours ago
    The last company I worked for still had customers they were dragging forward to get upgrades from coax connexted green screen terminals to modern network thin clients. It wasnt on DOS, but very old unix OS, tape drives for backups, parallel for printers, serial for scanners. No USB. Lovely troubleshooting when you were dealing with 30+ year old hardware setups. There was only one company that would even servicenthe green screens if they failed, and you couldn't buy them anymore.
  • ynac 13 hours ago
    It's not totally for business, but I run some antennae and radio telescopes that feed through a Gateway 386/33/16MB RAM. As well as a Getac, no idea what model, but it's from the early 2000s. They both feed through to a A/B switched Paradise CRT (so cute). dBase is on the list.
  • sgerenser 13 hours ago
    Does the idea make use of https://86box.net? Just heard of this recently on hn and it seems promising for anything that requires low level/cycle accurate emulation vs. your typical high level emulator.
    • mlaux 12 hours ago
      My idea is a DOS emulator with a really thorough log of every DOS interrupt called and I/O port interacted with. This could then be used to automatically, say, insert rows into a sqlite table when the DOS app updates a .DBF file, or forward GPIB data to a modern USB adapter. I wanted to avoid low level/cycle-accurate emulation as much as possible, only adding quirks as needed to support the most popular business application suites.
  • M95D 5 hours ago
    I had a functional STA Compact [1] coagulation analyzer until 2022. It ran a customized DOS version on a ITX computer board that was integrated into the analyzer. UI was in text mode and used the keyboard only. It had no mouse. The video in the link shows the UI for a few seconds at the end. We kept it functional as a backup and even used it a few days when the replacement broke down. It was one of the best analyzers I ever used.

    The newer version of that anaylzer, STA Compact Max [2] has mostly the same analyzer hardware, but newer ITX board inside. It runs Windows (XP, 7, 10...). Bugs galore.

    I know labs that used a Beckman-Coulter HmX hematology analyzer [3] until 2015 or so. That machine is attached to an external MS-DOS computer via a very thick cable and an ISA board. The cable connector looked a bit like a 68-pin SCSI-3. The software used VGA graphics mode.

      [1] https://www.youtube.com/watch?v=Kti6Zdyp8dQ
      [2] https://www.youtube.com/watch?v=MJan25vkpEA
      [3] https://www.soriaudio.com/index.php?mid=m_eqp&document_srl=62138152
  • NBJack 11 hours ago
    Do scanners count?

    I'm pretty sure they moved on from them, but a while ago I did seasonal work for a company that rented out scanners for year end inventory (tax related, IIRC). The scanners had to be "cooked" (flashed) on racks, boxed, and sent. The flashing usually worked, but on occasion, the scanner would fail the checksum or something and drop you into a DOS prompt.

  • EvanAnderson 2 hours ago
    A Customer of mine has an 386 machine with an ISA interface board connected to an optical comparator instrument. I believe they also still have some MS-DOS-based computers connected to CNC machines, too.

    I have two Customers who use DOS applications under DOSBox (a Clipper-based accounting package at one, and a Symantec Q&A-based application at another).

  • Froedlich 10 hours ago
    Me!

    I have a client with some business software that runs on DOS. They have a dozen seats. A single Linux server gives serves a dozen VNC sessions with the software running in DOSEMU. Printing is done with the Linux print stack and three Ethernet print servers.

    It has been working without a hitch since 2008. Oh, so has the server, which is a VirtualBox VM.

  • zerr 1 hour ago
    I've stumbled upon DOS on the LCD screen of the otherwise seemingly modern gas station.
  • andix 12 hours ago
    Just out of curiosity: is it possible to somehow attach an ISA Adapter via USB to a VM? ISA does depend a lot on DMA and timing, but the clock is only 8 mhz and gives a software layer on a modern cpu a lot of time to do stuff between ISA bus cycles.

    Keeping old hardware running is very fragile. Most spare parts are decades old now too, and nobody knows if they still work properly.

    • Teknoman117 12 hours ago
      To a VM? Possibly.

      The DMA might actually be the easy part.

      The main concern is how many VM exits per second a modern CPU can handle. Even though the interface is "slow", you can probably do ~500k to 1 million IN/OUTs or MOVs per second to ISA. You'd have to trap (VM exit) every access to a IO port or memory within the ISA window.

      During the pandemic I cobbled together a KVM-accelerated emulator for an old 386EX based board I had and trapping every memory access to IO was slower than the real hardware.

    • lysace 12 hours ago
      USB and VM latencies are both questionable here, I would think.

      ISA motherboards still work and have been mass produced in the hundreds of millions. (I have about a dozen in my retro closet.)

      The esoteric ISA expansion cards would be the bottleneck, not the motherboards.

      • andix 12 hours ago
        All those layers add some latency, but 8 mhz is really slow. USB 4 can do extremely low latency, otherwise PCIe over USB wouldn't work.
        • labcomputer 8 hours ago
          The problem is that a lot of those old ISA drivers were peeking and poking card registers as fast as the bus would allow, which was over 1 MHz (less than 1 microsecond per transaction), not DMAing data to RAM (though some did that too).

          With a modern 4 GHz CPU, that means your budget is only 4000 clocks per interrupt. The context save alone can make it hard to hit 1MHz, and you really want to have your interrupt code pinned to the L1 cache because a few memory reads will blow your entire budget.

          As nice as USB4 is, I’ve never heard anyone claim it has single-digit microsecond latency, to say nothing of sub-microsecond latency. The typically-quoted ~20 usec latency of USB4 limits it to around 50 kHz for an emulated ISA card.

          • rdtsc 6 hours ago
            Often people confuse latency vs throughput/bandwidth. With streaming and batching USB4 will shuffle a lot data through on average per second. But it will never hit reliable microsecond level or even submicrosecond latencies.

            At the same time ISA card will never reach 40Gbps throughout with CPU clocking at tens of MHz only or often less.

        • lysace 12 hours ago
          This looks quite interesting:

          https://www.reddit.com/r/vintagecomputing/comments/jbaw38/is... (2020)

          ISA-over-USB, using real ISA cards in an emulator

          https://github.com/Manawyrm/ISASTM/

  • ksec 6 hours ago
    We were talking about Visual FoxPro only a few days ago. [1] And one of those same companies in my comment [2] uses an old ordering system that is still in DOS and they boot up a VM to use it. They still have a printing machine ( not a normal printer ) for those order printing connected via a Parallel Port. I don't know the details of how that works though.

    And by the end of all that, the order will be Faxed. Manually.

    Did they tried to email it or automate it. Hell yes. Did it work? No.

    [1] https://news.ycombinator.com/item?id=49808023

    [2] https://news.ycombinator.com/item?id=49811716

  • mikewarot 5 hours ago
    The Gear cutting job shop I worked for had a CNC lathe running with a GE Computer from the late 1970s that stored data on punched Mylar tape, until it was bought out in 2019.

    The bevel gear generator setup was some formula calculations running in version 1 of TK!solver, which would have been a $5000 upgrade to get the latest version, so they ran them under MS-DOS in DOSbox, and saved the grief.

    Without that software, they would have to pay Gleason $500+ to do the calculations for each new gear setup.

    There are strong and reasonable reasons to keep very old systems alive in offline production environments.

  • nanochess 13 hours ago
    I've an AMD K5 processor machine running at 100 mhz. for testing Transputer ISA cards when someone buys one, I also use the same machine to format and copy my Pascal compiler into a pair of 5 1/4" floppy disks. All using DOS.
    • bartread 12 hours ago
      > Transputer ISA cards when someone buys one

      Your use of “when” is interesting - suggests it’s not that occasional. Wonder what people are doing with these nowadays.

  • zdragnar 11 hours ago
    It's been a few years now, but I know a major manufacturer had some windows XP boxes around because they were the newest hardware/software they could get with native parallel port support to interface with their machines.

    To give you an idea of the complexity of the manufacturing lines, shutting the machines down and starting them back up again was measured in days. Upgrading them would be obscenely expensive, let alone replacing them, just in the opportunity cost of not making anything alone.

    • mgk123 1 hour ago
      For anyone that needs true native serial & parallel ports, a Dell Latitude E series laptop (or Precision 7xx0) with docking station is an easily-available option.

      The last machines with dock port have 6th gen Core CPUs (Latitude E5x70), or 7th gen for Precision 7x20.

  • CobaltFire 12 hours ago
    I had to keep a disturbingly old machine with GPIB running until a few years back. They are still in operation in Australia (who we sold them to).

    It was a test/repair bench for military aircraft avionics, with the only flying platform left using it being the legacy F/A-18 (A/B/C/D). Harris H-100 minicomputer hooked to an HP terminal and several full racks of GPIB test equipment with half of a rack of solenoids for switching between stimulus and response and which pin.

    Not what you asked, but the question brought back memories.

  • smackeyacky 13 hours ago
    I know of a DOS machine at a wool testing place that uses an ISA card based imager for measuring the micron and other things. They also have a supporting DOS machine with a dBase looking database on it. When I spoke to the owner he didn’t really understand the risks involved in running ancient hardware and in fact had a storage room with period PCs in it if the machines failed. He didn’t have much of a backup plan for the imaging hardware though.

    My opinion is that if these guys are still running this gear, they already have a strategy in place (no matter how flawed) and would likely retire before throwing money at something they consider a non problem.

    Good luck with the idea. It likely is a tiny niche market with customisation for every customer and given they are normally hardware constrained AI may not be much of a help.

    All of them have no money as well.

    • mlaux 12 hours ago
      My idea is basically a DOS runtime with hooks on interrupts and I/O that would allow for either migrating databases to modern formats, or converting I/O accesses for modern USB peripherals. Customization for every customer and AI not being much of a help are pluses for me... lack of money not so much.
      • Froedlich 10 hours ago
        I have been porting sections of the business software I mentioned earlier from QuickBASIC on DOS (nice to have the source code!) to Tcl on Linux using ChatGPT to automate the conversion. It gets it right the first try, almost every time.

        The BASIC code is very simple by modern standards, and Tcl overlaps BASIC neatly, making conversion easy.

        Unfortunately it's just a short-term stopgap to add some features management suddenly can't live without, that weren't practical to implement in BASIC/DOS. They'll replace the whole stack with a commercial product and support contract when they find something they like.

    • Dwedit 12 hours ago
      You can still get ISA slots on systems as new as Broadwell with an adapter.
  • 83457 12 hours ago
    My dad ran a commercial 2-way radio business. There were multiple radios with programming software that would not work on anything above a 386 and DOS. He had a couple computers from the late-80s running for nearly 25 years, though I think he had to replace one of them with another of similar vintage. Also, had a 486 that he used for customer notes in WordPerfect up to about 2015.

    I suspect he could have found a way to use a newer computer, but if it ain’t broke…

    • betaby 10 hours ago
      Intel was seling 386 CPU up until 2007. I personally was using brand new special equipment with 386 soldered to custom MBs with no VGA, serial only access. I suppose you can purchase such boards from ebay/recyclers today.
    • Froedlich 10 hours ago
      I still have a circa-1996 486 running Windows 95. It has an EPROM burner card and software that I use to reprogram the ECM in my car.

      The cost of upgrading to modern software and hardware is substantial, plus the learning curve for something I only do rarely nowadays.

  • womod 11 hours ago
    We keep a FreeDOS machine at work for dialing in to configure and service paging terminals and using old two-way radio programming software.

    Most of the stuff I've moved over to run in DOSbox but it's still in use occasionally for the software that's difficult to port over.

  • DASD 13 hours ago
    Perhaps look into environmental services labs that do contract EPA work. I would not be surprised to see entire HP-Agilent(ISA-carded) - (think liquid chromotography analyzers) fleets that would match what you're looking for.
  • alightsoul 12 hours ago
    You're trying to create and sell a version of dos box? These companies have not replaced their computers because to the user there is no separation between the computer and the machine it controls. So the computer will be updated along with the equipment, which is not connected to the internet or a network anyways so it's not a cybersecurity risk. For the user, if it runs fine, there's no need to update just the computer, and the computer is updated along with the machine

    In other words, these are embedded systems.

    • mlaux 12 hours ago
      Not exactly, freely available solutions are already good enough for people who just want to run their apps on modern hardware, and have been for a long time. What I was thinking about writing is a tool that eases migration by using interrupt and I/O hooks to detect common patterns and, say, builds a modern SQLite database as the business uses their dBase program. Whether anyone actually needs this, I don't know.
      • alightsoul 9 hours ago
        There's a few car dealerships that still use databases from the 80s. As for why they haven't migrated, I'd guess must be reasons I'd assume at this point it's a choice they have made
  • saidnooneever 5 hours ago
    i know still some accountant who use a DOS program to do his work because he hates the fact modern UI has load times. slows him down too much o.O (his program is all keybinds).

    i do not have exp myself but i found it a delightful reasoning. i told him modern PC could also do the same on modern OS (ncurses or ratatui or so maybe) but that if he ask a programmer to make an upgrade he'd need to find the right kind of guy. He had someone do it few times but they came back with web interfaces.

  • lormayna 5 hours ago
    Few years ago I was working for a F500 company and during an assessment we discovered couple of OS/2 Warp machines that were controlling CNC equipment
  • Postosuchus 10 hours ago
    This is probably a wrong audience. Most people here are very technical - the kind that would not put up with tiptoeing around a sacred computer from decades ago running some magic software from the DOS era. This crowd will aggressively move it to modernized architecture or at least emulate it using a more modern platform.

    The company I worked at in the late nineties, used Managing Your Money (MYM) for bookkeeping - initially on a dedicated DOS machine. My colleague set up a DOSEMU-based emulator and moved the software to it (bye-bye, dedicated DOS machine!). Later, he re-wrote it in STk (Scheme w/ Tk bindings, running natively in Linux) as ageneral-purpose transaction storage. ¯\_(ツ)_/¯

    • fires10 10 hours ago
      This is not always possible when the systems are validated and regulated.
      • jlarocco 7 hours ago
        Yeah. Sometimes old hardware forces its hand and causes a big PITA.

        I had a job working on VAX/VMS around 2009, but it was actually an emulator running on a PC because they just couldn't find any hardware to fix the VAX. At some point before I joined they had to get a ton of government approvals to use the emulator.

        Fortunately they had a project to modernize the whole stack. And it was going to Solaris :-/

  • gerdesj 12 hours ago
    Until recently several customers have an industrial machine that boots DOS. I think the oldest effort we deal with is Win XP now. I do have a C>64 at home ...

    In a world that requires security audits etc here's some notes that might help:

    Scenarios: You have a device that only talks NetBIOS or even NetBEUI for file sharing. You need to get files to and from it and your CAD workstations run Windows 11 and anything less than SMB 3, with signing and sealing and all that jazz is laughable.

    ... Devices requiring ftp, telnet, serial over carrier pidgeon

    Solution options:

    Networking: The first job is to segregate your industrial gear from your general network and you might want to create two or more industrial gear and internet of things type networks with differing access policies. Start with one for now, you can improve it later.

    You use 801.1Q VLANS logically or physically (why the hell did I want to write literally?) separate via separate switches.

    Please do not skimp on this step. Buy a network bod to sort it out or put your IT bod on a course or hopefully they will have labbed this up at home already!

    Comms: Samba is bloody wonderful and speaks everything that MS has ever done and deprecated. Even Samba does need to be asked to start speaking some of those dialects again but it will.

    Put a Linux (other Unices are available) box on the same VLAN as your machines. You will need to set quite a few options relating to the minimum version for its server version. When talking to the machines, Samba is the server and when talking to your file server, Samba is the client.

    Create a data share on a Windows box on the corp LAN. For example it might be on a file server for multiple access or just a single CAD PC.

    Get the Samba box to mount that share to itself at say /srv/data_share_mc1

    Now get the Samba box to create a share from /srv/data_share_mc1 which it calls DAT_MC1 (8.3 chars for NetBIOS)

    With luck, you should be able to map DAT_MC1 on your machine.

  • techteach00 6 hours ago
    It's not DOS but my private school still uses an IBM 5100 to do payroll and record attendance.
  • nickhalfasleep 10 hours ago
    I know of some laboratories where they have a host of old machines for software to support some critical instruments that only runs off a dongle or an ISA card and it still does accurate work.
  • Aeolun 1 hour ago
    In the AI era, can’t we just release a new version of DOS?
  • reaperducer 13 hours ago
    Not DOS, but my company has a Windows XP machine with a dialup connection that I have to keep running for obtuse legal reasons.

    If it goes down, the company gets fined. It happened in the gap between my predecessor leaving, and me being hired.

    • gerdesj 12 hours ago
      Does it have to be a XP box or is just keeping a serial dialup connection working the key?
    • andix 12 hours ago
      Is it a physical machine and not a VM? I already had issues with getting XP compatible spare parts years ago. Had to buy used parts that were already pretty old (so high risk of failing again).
      • reaperducer 12 hours ago
        It's a physical machine.

        Fortunately, I don't have to deal with swapping parts. There's an outside contractor on call 24/7 for that.

        The last time I saw it was about two years ago when I taped yet another piece of paper to the filing cabinet it sits on reading "DO NOT TURN OFF UNDER PENALTY OF LAW!"

        Someone keeps taking the paper down.

        • andix 12 hours ago
          Put a proper sticker on, that can't be removed easily.
  • yanren36 3 hours ago
    How i can bring my blogger to rank first Site link Factaxy.com
  • myself248 8 hours ago
    A few years ago, I helped repair a broken USB port, on a USB-floppy emulator...

    ...which was so the operators could sneakernet their NC tape files into an IBM PC 5150 that thought it was talking to a floppy drive, of course...

    ...which hosted an ISA card that emulated the punch-tape reader that the NC lathe had originally been designed with.

    The NC lathe hadn't missed a beat in 50+ years, why mess with what works?

  • newman314 12 hours ago
    I virtualized a bunch and they seem to work well. At one point, I even had Ultima running on one. =D
  • al_borland 12 hours ago
    It’s gone now, but we used to have a random OS/2 box well past the point where that was extremely weird.
    • gerdesj 12 hours ago
      What's weird about Warp?
      • Froedlich 10 hours ago
        Like most people who bought into the OS/2 hype, I bailed after 1.3.
      • al_borland 8 hours ago
        The weird part was still using it into the 2010s.
  • Natsu 10 hours ago
    I used to be doing that, but this was a bit over a decade ago at this point. There was an SBC with DOS on a chip that connected to Novell Netware. I set a few variables in autoexec.bat, let it connect to the network drive, then had it run a script from there to admin them / do backups (by which I mean xcopy the C: drive).

    These were for some industrial CNC machines with a poorly version-controlled app (send us the single-file .c for the program, we'll make changes & recompile for you, then send back a new .c and .exe file) that would just malloc() all the memory on the machine for a million element array instead of tracking the 1k or so unit IDs a more efficient way. They were six digits long, it worked... mostly.

    I kept a 3.5 floppy with the contents of sys a: that I used to run sys c: after restoring a machine from backup in my office.

    EDIT: oh, and of course by "restoring from backup" I mean reversing the xcopy to copy everything from the network drive's copy back to C:

    EDIT2: My memory is going, they didn't use malloc() at all, anywhere in the programs, they just had a static million element array.

  • api 10 hours ago
    Not current and not DOS... but years ago, around 2011, I helped set up a series of QEMU emulators running DEC Ultrix and MIPS Unix software that called out and retrieved data from weather stations only reachable by modem. The software had been written years prior in C and nobody had the source.

    The box running the QEMU emulators had a bunch of old US Robotics modems hanging off it via USB serial dongles.

  • TMWNN 11 hours ago
    >Anything with a parallel port dongle?

    https://news.ycombinator.com/item?id=46849567

  • ironqcold 9 hours ago
    [dead]
  • vancekai 8 hours ago
    [dead]
  • Alex131313 13 hours ago
    [flagged]
  • huflungdung 13 hours ago
    [dead]