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guenthert 15 hours ago [-]
Holy cow, a 386 with VGA and SoundBlaster on a $1 MCU?
I recall VICE emulating the Brotkasten on 386 PCs some thirty years ago, later UAE doing it for Amiga. How long til my currently running system (anno 2016) is being emulated?
supergarfield 12 hours ago [-]
Maybe never with current technology? Looking just at the CPU and assuming you need comfortable IPC overhead for emulation, the 386 was from early in the Dennard scaling era and modern CPUs are 1000x or more faster single-thread. Since maybe 2012 that hasn't moved anywhere near that, certainly less than 10x.
For the GPU things are potentially looking better! But since distributed shaders/kernels are higher-level compiled for your specific device, there's less of a need for emulation.
theamk 12 hours ago [-]
Either "already" or "not any time soon", depending on how you count.
Already - because you have VMs and backwards compatibility. As long as you keep using Intel x86_64, your apps would run, no emulation needed. Or you can use the VM.
Not any time soon - because the computers are not speeding up that fast. 10 year old computers are still being used today, and even the latest CPUs are not orders of magnitude faster. So for a full-system emulation, the most well-known ones is x86 VM's on Apple Silicon, and according to reports, full-system mode is still not close to regular PCs.
kevin_thibedeau 10 hours ago [-]
16-bit x86 code dependent on interacting with real hardware under precise timing doesn't always work well in a VM.
sillywalk 7 hours ago [-]
> 16-bit x86 code dependent on interacting with real hardware under precise timing doesn't always work well in a VM.
This reminds me of the 8088mph demo - 1k colours in CGA, and a bunch of other impressive stuff.
8088 MPH: We Break All Your Emulators (oldskool.org)
319 points by drv on April 8, 2015 | hide | past | favorite | 99 comments
true, but the question was about "my currently running system (anno 2016)" - which means intel core most likely. And at that generation, there requirements for precise timing is extremely rare, it's mostly PCI/PCIe devices and they can be shared with VMs just fine.
peter_d_sherman 7 hours ago [-]
>Holy cow, a 386 with VGA and SoundBlaster on a $1 MCU?
The right software -- really does add value(!) to (let's-just-say-it-isn't-an-nVidia-GB300!) hardware, now doesn't it? :-)
I don't know about anyone else -- but I'm sold!
The value proposition on this one is truly awesome!
dvdkon 16 hours ago [-]
It's really cool what can be done today with just an MCU that has sufficiently flexible IO. What's the performance like?
cold_pizz4 17 hours ago [-]
I love it!
The RP2350 is probably the most underrated microcontroller available today.
IshKebab 16 hours ago [-]
Overrated surely? It's a pretty bog standard MCU, no wireless support, mediocre deep sleep. I don't know why you'd pick it over an ESP32 or nRF5x.
The only standout feature is PIO which is definitely interesting but very niche. It's also patented so say goodbye to any portability or FOSS vibes. (If you want a FOSS version btw, check out https://baochip.com/)
If it didn't have the Raspberry name behind it nobody would even have heard of it.
willis936 16 hours ago [-]
The PIO are pretty great and not niche. Almost any embedded application needs mixed signal interfaces. You could say embedded applications are niche, but not that embedded applications needing mixed signal interfaces.
A serious warning: read the RP2350 errata carefully. You may be better off buying old 2040 inventory.
sh-run 13 hours ago [-]
RP2350 adds secure boot and encrypted boot. I am working on a little hardware device for a CTF and selected it as my MCU so participants can't just dump the flash to grab the flags.
vardump 13 hours ago [-]
> read the RP2350 errata carefully
Even the latest rev? Can you elaborate a bit?
kjs3 11 hours ago [-]
The smart engineer always reads the errata carefully.
Neywiny 13 hours ago [-]
Mixed signal means analog and digital
IshKebab 6 hours ago [-]
> Almost any embedded application needs mixed signal interfaces.
For the vast majority of embedded applications you can simply pick an MCU that has the hardware peripherals they need. That's why XMOS was never very successful. (They thought of this idea long ago.) Not saying it isn't cool.
Lerc 11 hours ago [-]
If you want something that can do some dumb buttons and lights handling on a mass consumer device, it's not ideal.
I would say it is still underrated.
PIO combined with DMA and the independent bus SRAM banks allow for immense combinations of capability.
If you want to do something digital and specific beyond a few MHz the the RP2350 raised the ceiling of what you can do before requiring hardware or FPGA.
It still has some areas where it could be improved, but most of thise would not have been apparent until you really stretched the design.
Having extra PIO GPIO without physical pins but the ability to configure connecting pairs together in software would add a lot of capability.
Perhaps an interesting test/benchmark would be to get a microcontroller to pretend to be an SRAM (or better yet two independently accessed SRAMs) while outputting the lyrics to still alive on a serial link.
The virtual SRAM performance characteristics of timing tolerances and latency would be a respectable approximation for arbitrary digital signal handling that any particular MCU might be able to manage.
riskable 14 hours ago [-]
Are you kidding me? It costs a fraction of the competition and you can use just about any pin for anything you want! It makes designing boards for the RP series so simple and easy!
Contrast that with STM32 where you have to constantly reference the data sheet to make sure you're using the correct pins for say, I2C when you're running in a particular mode. And since you're running in that mode, you now can't use other pins for certain things. Ugh! I hate it!
Then there's the issues with picking the right-size part number and making sure the pins you want are 5V tolerant, checking that you're using the correct ADC, and... Ugh! It's a pain in the ass!
Other chips aren't much better as they all have those same problems.
ESP32 is nice because of the zillions of built-in peripherals but configuring the damned thing can get really complicated really fast. It's so complicated, in fact, that they had to make a Makefile (as in `make menuconfig`) that rivals the Linux kernel in the sheer number of options/submenus.
IshKebab 6 hours ago [-]
nRF5x also has completely configurable pins, and if you're worrying about awkward pinouts making PCB design slightly more annoying then you're definitely not in a cost sensitive project.
12 hours ago [-]
aswanson 6 hours ago [-]
Esp32 is a power hog and lacks pin configurability.
12 hours ago [-]
paulryanrogers 4 hours ago [-]
Is this an emulator or firmware that makes the Pi a cycle accurate implementation of 386, just with a bit of hardware shims for modern accessories?
ilaksh 10 hours ago [-]
The problem is PC programs assume 640kb of RAM and the RP2350 has 512kb + 16kb cache SRAM so anything that goes past that has a sudden 40 cycle access delay.
So even if you account for the RP2350 being 6 times faster than the RP2350, I think the emulation would randomly start to stutter a lot in certain circumstances waiting to access that part of the memory.
luma 8 hours ago [-]
That isn't true to my knowledge for old DOS applications (including games). 640kb was the upper limit, not the lower bound.
ilaksh 7 hours ago [-]
yeah but for 386?
luma 5 hours ago [-]
Same answer. You could enter 386 protected mode with less than 640kb installed.
dark-star 6 hours ago [-]
How is the RP2350 6 times faster than the RP2350? That must be a typo...
gxd 15 hours ago [-]
I had Slackware CDs in the nineties! They had a minimalist label and came with no jewel case (rubber band if I recall correctly).
I've been meaning to rediscover the CICA and Simtel collections. Maybe that's what I needed!
zabriel_goss 12 hours ago [-]
What a long way to have come from the beige towers!
weinzierl 18 hours ago [-]
Looks like it can even run Windows 96. Incredibly cool. I'll have to try if it runs my old Slackware kernal 1.2.13 some time. I used it with a 4MiB, 25Mhz 386 DX back in the time, so it should.
xhrpost 17 hours ago [-]
Did not realize that Win95 can technically run on a 20Mhz 386DX.
badsectoracula 16 hours ago [-]
It "technically" can - i used Win95 on an AMD 386DX with 4MB of RAM back in the 90s for a little. Most of the time was spent waiting for the computer to do something while the HDD was constantly working.
The Pentium MMX with 32MB i replaced it with was MUCH faster, practically everything was instant.
nullsmack 12 hours ago [-]
I tried installing it on my 20mhz 486 IBM but the install never would finish even though the minimum specs listed 386. I always thought that was being too generous. I did use it on faster 486's at some point in school (I think 66mhz or faster?)
glitchc 12 hours ago [-]
Yup, the RAM was the main bottleneck. 8MB was the minimum for Win9x, 16MB and above led to a fast experience.
cgearhart 15 hours ago [-]
Back in the mid 90’s I got it to “run” on a 386, but it was miserable. It was basically wondering if it was hung or just really slow on every command or mouse click.
nottorp 15 hours ago [-]
Yes. I remember one of the MS guys saying the goal for win 95 was win32s equivalent performance on a 386 with 4 Mb ram. But win32s performance on that hardware was crap :)
st_goliath 16 hours ago [-]
> Win95 can technically run on a 20Mhz 386DX
s/technically/allegedly/
supposedly with a minimum of 4M RAM even! [1] I have a machine with twice that clock and twice that RAM that a friends parents wanted to toss out[2]. I spent the better part of a day getting Windows 3.11 and Office 4.3 to run. Playing around with it for a bit, I highly doubt that Windows 95 on minimum requirements would be anything but endlessly frustrating. I was not masochistic enough to try.
I ran Windows 95 on a 386SX-16 with an 80387, with 5MB of ram for a year as my main machine. It ran about as well as 3.1 did. The only real drawback was the disk space required for 95 over 3.1 + DOS.
weinzierl 17 hours ago [-]
Good question. I ran Slackware Linux and DOS 5.0 on mine. I think Win95 was my Pentium 100 MHz already so it sounds a bit sus, but the FAQ section of OP had items about Win95, that is where I got the idea from.
lightedman 13 hours ago [-]
We had Win95 running on a 25MHz 4MB FPRAM 286 back in high school. Poor teacher, half of first period was roughly how long it took to boot up, only for them to exit into DOS mode because the grading software and report card software was DOS-native and would hang if you tried running it under the GUI.
vardump 13 hours ago [-]
You certainly did not, as Win95 requires 32-bit, 80386 or better. 286 was a 16-bit CPU.
lightedman 12 hours ago [-]
Windows 95 had a beta build for 286 systems, which is what this system 'ran.'
Bet you don't even know about Windows 97.
skissane 4 hours ago [-]
> Windows 95 had a beta build for 286 systems, which is what this system 'ran.'
I think you are confused. There was an Windows 95 build 286, but despite its name it didn't run on a 286 – it was just an incrementing counter which happened to have reached that number.
At some point early in Windows 95's development, Microsoft dropped the standard-mode only 286 kernel, KRNL286.EXE. They also dropped 16-bit-only standard mode from KRNL386.EXE; but KRNL386.EXE required a 386 even for standard mode.
The earliest leaked Windows 95 build, build 22, still has KRNL286.EXE in it, but it is unchanged from Windows for Workgroups 3.11, and doesn't actually work – other Windows 95 components require new APIs which Microsoft added to KRNL386 but didn't bother adding to KRNL286. By the time we get to build 286, KRNL286 was long gone.
In principle, you could likely patch early Windows 95 builds to run on a 286, but I don't think anyone has actually tried. At a minimum, you'd need to add the missing APIs to KRNL286.EXE
Taking you at your word, I suspect what you may have actually saw was https://en.wikipedia.org/wiki/Calmira – an open source project which gives Windows 3.x a Windows 95-style interface – or if not Calmira, other people implemented the same idea independently, e.g. the shareware Mask98 package – http://www.win3x.org/win3board/viewtopic.php?t=1262&view=min – however, this had nothing to do with Microsoft; Microsoft could have done something like this, but they had no commercial interest in doing so.
> Bet you don't even know about Windows 97.
That is just an unofficial/unlicensed third-party distro of Windows 3.11 with Calmira bundled.
Separately, "Windows 97" was also what Microsoft once planned to call "Windows 98", but they weren't able to finish it in time to release it in 1997
Narishma 9 hours ago [-]
It did not and it wouldn't have made any sense. By the time Windows 95 came out 286 systems were obsolete. They could barely run Windows 3.
fifilura 18 hours ago [-]
(slackware) Just need to find where you stored all 20 floppy disks...
weinzierl 17 hours ago [-]
I think it came with two 3.5" disks, a bootdisk and a rootdisk, as well as two CDs. One was the actual distro, the other a sunsite mirror.
At least that is what I remember and while that memory might be hazy I know exactly where my precious is.
rwmj 17 hours ago [-]
I definitely remember installing it off 20+ floppies onto a 386 back in the day. Most of the disks contained packages and you didn't need to install all of them though.
jalk 15 hours ago [-]
IIRC Emacs took up a significant number of disks
tosti 15 hours ago [-]
To be fair, that's pretty much an entire operating system. Just one that lacks its own kernel. It even takes a while to boot up!
my123 14 hours ago [-]
Eight Megabytes And Constantly Swapping
soneil 13 hours ago [-]
Eight Megabytes would be a feature, these days.
gamedna 13 hours ago [-]
Early releases of Slackware were only floppy. The boot/root CD release came later. I fondly recall wasting hours in a computer lab @ university using 20 Sun Sparcstation 2 floppy drives to write the slackware floppies for me and my friend. Walking out with a brick of floppies was pure bliss (achievement unlocked).
ilaksh 10 hours ago [-]
I don't know if they have some kind of magically genius caching system but the chip only has 512kb of SRAM and a little cache and the rest has to be managed by flash memory which is like 30+ times slower so I dunno about the performance of that.
Narishma 9 hours ago [-]
The boards using this chip typically have 8 MB of PSRAM from what I've seen.
ilaksh 9 hours ago [-]
yeah but the PSRAM is going to cause a delay
dark-star 6 hours ago [-]
it's not that bad. At 120MHz, the PSRAM still gets only around 90-100ns per word in the worst case. If you use some SRAM for caching and do bulk transfers, you can get that down quite a bit. Also you can easily overclock the PSRAM to 133MHt (10 decrease in latency) with no problem, maybe even (much?) more.
normal dynamic RAM back then was at 60-70 ns so it's really not that bad. And YT videos show that it also works fine in practice
broswell 11 hours ago [-]
Which of the 4 boards on do you recommend as easiest? I would love to demo at the Computer Museum @ System Source https://museum.sysrc.com
It looks like I would have to build my own frank board. Any off the shelf boards?
Nexxxeh 9 hours ago [-]
To save anyone the Google, there's an S missing from the URL.
That one is offering Pentium Pro and SSE3 emulation. Not too shabby.
burstmode 17 hours ago [-]
Does it emulate RS232 ports and printer ports as well ? I did'nt find anything. Then it would be possible to reuse old embedded equipment.
kees99 16 hours ago [-]
No, it doesn't.
Also this doesn't emulate ISA bus, where one could plug one of those "multi-io" cards to get rs232/printer ports.
Which is a shame. There are plenty of GPIO pins to fit full ISA on RP2350 (at least on "B" variant), and those GPIO are supposedly 5V-tolerant (with sufficiently recent silicon revision). So hardware-wise, it's just a matter of wiring up an ISA slot directly to the RP chip.
jasomill 10 hours ago [-]
This could be useful on its own to create an ISA-over-USB bridge in conjunction with either a kernel driver or a user-mode PC emulator.
dark-star 6 hours ago [-]
it would be awesome if there was an ISA bus emulation using some sort of modern protocol. You could create "modern" ISA cards using an RP2350 on every card that does the emulation, to split emulation between multiple RP2350's (one emulates a VGA card, one emulates a sound card, one emulates a network card, etc.)
Bonus points for a standardized connector that everyone could develop towards. Imagine a tiny ISA PC that you could place on your desktop, swap miniscule (ISA)-cards in and out of, and play retro games etc.
kees99 4 hours ago [-]
"Modern" tiny ISA would probably be LPC [0] which is a relatively simple encapsulation/serialization format for ISA that preserve full software compatibility, and can transport ISA signals over as few as 8 pins.
This thing was quite ubiquitous for inter-connecting some low-speed things within PC motherboards in the early 2000s. Although physically separate LPC cards did exits, those were rare and connector/pinout was never standardized.
> Then it would be possible to reuse old embedded equipment.
Unlikely, virtualization/emulation has been a thing well before this project and you can just buy USB to RS232 adapters. There are GPIO solutions for industrial PCs other than the parallel port. Or you can simply buy new industrial PCs which have those ports.
If you find an industrial appliance controlled by genuine old PC hardware that hasn't been replaced, the RS232 ports are the least of your concerns.
In my experience, such machines usually have something insanely proprietary plugging into a custom ISA card, and whatever is connected to it usually doesn't take too kindly if the bus timings are off. And neither does the accompanying bare metal software that relies heavily on timing loops and hardware peculiarities.
HeyLaughingBoy 9 hours ago [-]
I've been holding on to a couple of fanless industrial PCs as much for their cases (I could drive my truck over one, and it wouldn't even make a dent) as for any possible future uses. As time moves on, being able to use them looks less and less likely.
nickcw 14 hours ago [-]
Was the performance mentioned anywhere - I couldn't find it on the page?
dingdingdang 10 hours ago [-]
Should be on the fast end of the 386 spectrum since it tentatively supports 486 and 586 architectures too.
LeFantome 9 hours ago [-]
I don’t know how fast it is but that does not really follow. They added those instructions so that Linux would boot. Linux assumes Pentium and no longer boots on 386 or even 486 for the latest kernels.
The presence of instructions first added in the Pentium really does not tell you anything about performance.
shrubble 13 hours ago [-]
Technically you could run OS/2 on it, I think.
Or Plan9 for i386.
astrodust 9 hours ago [-]
With 8MB it'll be snug.
jwrallie 17 hours ago [-]
Really cool, wondering if it can be ported to the PicoCalc.
joshmarinacci 13 hours ago [-]
Wow. How can it do this without an MMU?
iberator 13 hours ago [-]
MMU can be emulated as part of emulated architecture.
Its totally possible to have software only mmu.
probably faster downloading it than searching around in the attic ;-)
momocowcow 17 hours ago [-]
yes, but those screenshots are EGA
dark-star 5 hours ago [-]
At least the Wolfenstein screenshot is VGA, not EGA. Yes, it looks weird with that dithering effect, but it's still VGA (too many/wrong colors for EGA, and also: Wolfenstein never was released with EGA graphics in the first place)
I recall VICE emulating the Brotkasten on 386 PCs some thirty years ago, later UAE doing it for Amiga. How long til my currently running system (anno 2016) is being emulated?
Figure 6 in "A New Golden Age for Computer Architecture" is a good representation of that effect: https://dl.acm.org/doi/epdf/10.1145/3282307.
For the GPU things are potentially looking better! But since distributed shaders/kernels are higher-level compiled for your specific device, there's less of a need for emulation.
Already - because you have VMs and backwards compatibility. As long as you keep using Intel x86_64, your apps would run, no emulation needed. Or you can use the VM.
Not any time soon - because the computers are not speeding up that fast. 10 year old computers are still being used today, and even the latest CPUs are not orders of magnitude faster. So for a full-system emulation, the most well-known ones is x86 VM's on Apple Silicon, and according to reports, full-system mode is still not close to regular PCs.
This reminds me of the 8088mph demo - 1k colours in CGA, and a bunch of other impressive stuff.
8088 MPH: We Break All Your Emulators (oldskool.org)
319 points by drv on April 8, 2015 | hide | past | favorite | 99 comments
https://news.ycombinator.com/item?id=9338944
https://trixter.oldskool.org/2015/04/07/8088-mph-we-break-al...
The right software -- really does add value(!) to (let's-just-say-it-isn't-an-nVidia-GB300!) hardware, now doesn't it? :-)
I don't know about anyone else -- but I'm sold!
The value proposition on this one is truly awesome!
The only standout feature is PIO which is definitely interesting but very niche. It's also patented so say goodbye to any portability or FOSS vibes. (If you want a FOSS version btw, check out https://baochip.com/)
If it didn't have the Raspberry name behind it nobody would even have heard of it.
A serious warning: read the RP2350 errata carefully. You may be better off buying old 2040 inventory.
Even the latest rev? Can you elaborate a bit?
For the vast majority of embedded applications you can simply pick an MCU that has the hardware peripherals they need. That's why XMOS was never very successful. (They thought of this idea long ago.) Not saying it isn't cool.
I would say it is still underrated.
PIO combined with DMA and the independent bus SRAM banks allow for immense combinations of capability.
If you want to do something digital and specific beyond a few MHz the the RP2350 raised the ceiling of what you can do before requiring hardware or FPGA.
It still has some areas where it could be improved, but most of thise would not have been apparent until you really stretched the design.
Having extra PIO GPIO without physical pins but the ability to configure connecting pairs together in software would add a lot of capability.
Perhaps an interesting test/benchmark would be to get a microcontroller to pretend to be an SRAM (or better yet two independently accessed SRAMs) while outputting the lyrics to still alive on a serial link.
The virtual SRAM performance characteristics of timing tolerances and latency would be a respectable approximation for arbitrary digital signal handling that any particular MCU might be able to manage.
Contrast that with STM32 where you have to constantly reference the data sheet to make sure you're using the correct pins for say, I2C when you're running in a particular mode. And since you're running in that mode, you now can't use other pins for certain things. Ugh! I hate it!
Then there's the issues with picking the right-size part number and making sure the pins you want are 5V tolerant, checking that you're using the correct ADC, and... Ugh! It's a pain in the ass!
Other chips aren't much better as they all have those same problems.
ESP32 is nice because of the zillions of built-in peripherals but configuring the damned thing can get really complicated really fast. It's so complicated, in fact, that they had to make a Makefile (as in `make menuconfig`) that rivals the Linux kernel in the sheer number of options/submenus.
So even if you account for the RP2350 being 6 times faster than the RP2350, I think the emulation would randomly start to stutter a lot in certain circumstances waiting to access that part of the memory.
I've been meaning to rediscover the CICA and Simtel collections. Maybe that's what I needed!
The Pentium MMX with 32MB i replaced it with was MUCH faster, practically everything was instant.
s/technically/allegedly/
supposedly with a minimum of 4M RAM even! [1] I have a machine with twice that clock and twice that RAM that a friends parents wanted to toss out[2]. I spent the better part of a day getting Windows 3.11 and Office 4.3 to run. Playing around with it for a bit, I highly doubt that Windows 95 on minimum requirements would be anything but endlessly frustrating. I was not masochistic enough to try.
[1] https://en.wikipedia.org/wiki/Windows_95#System_requirements
[2] https://goliath32.com/hw/machines.html#pc386
Bet you don't even know about Windows 97.
I think you are confused. There was an Windows 95 build 286, but despite its name it didn't run on a 286 – it was just an incrementing counter which happened to have reached that number.
https://betawiki.net/wiki/Windows_95_build_286
At some point early in Windows 95's development, Microsoft dropped the standard-mode only 286 kernel, KRNL286.EXE. They also dropped 16-bit-only standard mode from KRNL386.EXE; but KRNL386.EXE required a 386 even for standard mode.
The earliest leaked Windows 95 build, build 22, still has KRNL286.EXE in it, but it is unchanged from Windows for Workgroups 3.11, and doesn't actually work – other Windows 95 components require new APIs which Microsoft added to KRNL386 but didn't bother adding to KRNL286. By the time we get to build 286, KRNL286 was long gone.
https://betawiki.net/wiki/Windows_95_build_22
In principle, you could likely patch early Windows 95 builds to run on a 286, but I don't think anyone has actually tried. At a minimum, you'd need to add the missing APIs to KRNL286.EXE
Taking you at your word, I suspect what you may have actually saw was https://en.wikipedia.org/wiki/Calmira – an open source project which gives Windows 3.x a Windows 95-style interface – or if not Calmira, other people implemented the same idea independently, e.g. the shareware Mask98 package – http://www.win3x.org/win3board/viewtopic.php?t=1262&view=min – however, this had nothing to do with Microsoft; Microsoft could have done something like this, but they had no commercial interest in doing so.
> Bet you don't even know about Windows 97.
That is just an unofficial/unlicensed third-party distro of Windows 3.11 with Calmira bundled.
https://crustywindo.ws/Windows_97
Separately, "Windows 97" was also what Microsoft once planned to call "Windows 98", but they weren't able to finish it in time to release it in 1997
At least that is what I remember and while that memory might be hazy I know exactly where my precious is.
normal dynamic RAM back then was at 60-70 ns so it's really not that bad. And YT videos show that it also works fine in practice
It looks like I would have to build my own frank board. Any off the shelf boards?
https://museum.syssrc.com/
Also this doesn't emulate ISA bus, where one could plug one of those "multi-io" cards to get rs232/printer ports.
Which is a shame. There are plenty of GPIO pins to fit full ISA on RP2350 (at least on "B" variant), and those GPIO are supposedly 5V-tolerant (with sufficiently recent silicon revision). So hardware-wise, it's just a matter of wiring up an ISA slot directly to the RP chip.
Bonus points for a standardized connector that everyone could develop towards. Imagine a tiny ISA PC that you could place on your desktop, swap miniscule (ISA)-cards in and out of, and play retro games etc.
This thing was quite ubiquitous for inter-connecting some low-speed things within PC motherboards in the early 2000s. Although physically separate LPC cards did exits, those were rare and connector/pinout was never standardized.
[0] https://en.wikipedia.org/wiki/Low_Pin_Count_bus
Unlikely, virtualization/emulation has been a thing well before this project and you can just buy USB to RS232 adapters. There are GPIO solutions for industrial PCs other than the parallel port. Or you can simply buy new industrial PCs which have those ports.
If you find an industrial appliance controlled by genuine old PC hardware that hasn't been replaced, the RS232 ports are the least of your concerns.
In my experience, such machines usually have something insanely proprietary plugging into a custom ISA card, and whatever is connected to it usually doesn't take too kindly if the bus timings are off. And neither does the accompanying bare metal software that relies heavily on timing loops and hardware peculiarities.
The presence of instructions first added in the Pentium really does not tell you anything about performance.
Or Plan9 for i386.
probably faster downloading it than searching around in the attic ;-)