Odd I never knew it was a commercial product.

It’s unfortunate I didn’t find emu386 until 1998, I could have used it in 1992

rmay635703 wrote on 2025-08-22, 13:33:

Odd I never knew it was a commercial product.

It’s unfortunate I didn’t find emu386 until 1998, I could have used it in 1992

Sadly, first version was in 97. I remember back on time i have a old version without the nag screen, was still freeware until v1.00, later the author add the nag screen and become shareware. I will be happy to paid the 10 usd he ask..! I use a lot

Software for 286, first released in 1997, ie. Pentium 2 era...
No wonder I've never even heard about it until recently.

Grzyb wrote on 2025-08-22, 16:15:

Software for 286, first released in 1997, ie. Pentium 2 era...
No wonder I've never even heard about it until recently.

Remember back on time i get the 1.0 version on a floppy from a friend that was super happy to run some 386 software, and he came home to give me the floppy because he knew i have a 286 too

I used it for some years, until 99, that i leave home to live alone, and i buy a 486 jaja really no joke

what i did not know there was a 1.34 version, i always use the 1.0 one, sadly i lost it

Grzyb wrote on 2025-08-22, 16:15:

Software for 286, first released in 1997, ie. Pentium 2 era...
No wonder I've never even heard about it until recently.

You've must been from a more wealthier country then. ;)
Over here in good, poor old Germany, I had a hot-rod 286 PC on my desktop up until 2000.
Even installed the Y2K patches for Windows 3.1 in 1999 or 2000, when Microsoft released that Year 2000 CD.
My dad had owned a 386 PC and a 486 laptop until by that time.
By 1996/97, I heard of the Pentium 1 first time. 486 PCs were still common.

Edit: Picture of Y2K CD:
https://commons.wikimedia.org/wiki/File:Ms-Y2K-RCD.jpg

Jo22 wrote on 2025-08-22, 21:49:

You've must been from a more wealthier country then. 😉

Hehe, quite contrary...
In the West, it was common for a PC to serve as a home computer already in the XT/286 era.
In Poland, it was mostly 8-bit stuff, or Amiga 500 in the best case.

In my bubble - and my bubble was very tech-savvy! - PCs only began to appear at homes in 1993+, when it didn't make sense to purchase anything below 386SX.

So naturally, in late 90s, the share of 286 machines in the "installed base" was negligible.
I only recall using them at the university for transferring data to/from diskettes - there were rooms with Unix terminals which lacked floppy drives, so there were also old PCs in the corners, solely for the purpose of FTPing stuff between floppies and the Unix host.

Grzyb wrote on 2025-08-23, 00:12:

Hehe, quite contrary... In the West, it was common for a PC to serve as a home computer already in the XT/286 era. In Poland, it […]
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Jo22 wrote on 2025-08-22, 21:49:

You've must been from a more wealthier country then. ;)

Hehe, quite contrary...
In the West, it was common for a PC to serve as a home computer already in the XT/286 era.
In Poland, it was mostly 8-bit stuff, or Amiga 500 in the best case.

Makes sense. So the the high-end chips of the 80s weren't mainstream and had been skipped by home users, basically.

I didn't know that, since my only comparison was/is eastern PCs from former GDR.

And they had an 80286 at the very best; it was covered in one of the last books printed in 1990.
Maybe that's also why the 80286 lived a bit longer here.

ATs with 286 running DOS were quick enough to most users in western/eastern part of the country.
Lightweight Windows 3 use was considered possible, too.

Grzyb wrote on 2025-08-23, 00:12:

In my bubble - and my bubble was very tech-savvy! - PCs only began to appear at homes in 1993+, when it didn't make sense to purchase anything below 386SX.

Ah, I see. Maybe that wasn't bad, after all.
You guys were lucky to have started in the golden era of DOS gaming! ^^

@theelf I thought about this. Maybe it's possible to make a patch file available somewhere else?
I remember that the ROM translation community uses IPS files to legally provide patches.
The files contain merely changes to the input file and no copyrighted material.
A graphical utility, Lunar IPS, is quite popular I vaguely remember. Again, it's just an idea.

Jo22 wrote on 2025-08-27, 02:16:

Makes sense. So the the high-end chips of the 80s weren't mainstream and had been skipped by home users, basically.

Let my clarify: 286 wasn't completely skipped.
In the early 90s, the "AT/40/mono" did have its share - but it wasn't the default computer to buy for a novice user, rather something for the experienced who needed a serious machine for serious applications.

Also, it seems that upgrade paths were different...
In the West - just buy a brand new PC, and give the old one to children.
In Poland - only replace the most obsolete component, usually the motherboard+CPU combo.
The 286 boxes from early 90s were still in active service a few years later, but they weren't 286 anymore - they got upgraded.

Grzyb wrote on 2025-08-27, 04:02:

Jo22 wrote on 2025-08-27, 02:16:

Makes sense. So the the high-end chips of the 80s weren't mainstream and had been skipped by home users, basically.

Let my clarify: 286 wasn't completely skipped.
In the early 90s, the "AT/40/mono" did have its share - but it wasn't the default computer to buy for a novice user, rather something for the experienced who needed a serious machine for serious applications.

Oh, okay. I see. My bad. Thank you very much for the information! 🙂

Grzyb wrote on 2025-08-27, 04:02:

Also, it seems that upgrade paths were different...
In the West - just buy a brand new PC, and give the old one to children.

Probably true, I won't disagree - I don’t know for sure how it was over here, sadly.
I've reached a point in life where I nolonger know for sure what to believe and often question my own memories.

It doesn't help that my fellow citizens have different views all the time, either.
Maybe I'm just weird, don’t know. My father is a radio amateur, I'm an optimist and tinkerer.. Not exactly normal.

All I can say is that I think that I got my 286 in early 90s as second hand.
It was sold cheaply because of a company dissolution, I vaguely remember.
And perhaps because the writing was on the wall for 16-Bit computers..

Either way: In the house floor, down near the stairs I had to choose between an
ugly IBM PS/2 colour monitor and a pretty monochrome monitor, both VGA.
(I've chosen the ugly IBM, which served me well for years.)

A bit later, my dad and me then installed 4x 1MB SIMMs and an 80MB Conner HDD.
Later, a multimedia kit consisting of a PAS16 and a Sony SCSI CD-ROM followed, as did a Mustek handy scanner.

It basically was a barebone PC (floppy/motherboard/PSU/CPU) which then got same internal expansion as a budget 386 PC.
Performance wise, it must have been similar to an Amstrad Mega PC of same time (a 386SX system).

The on-board VGA on my PC was an 8-Bit ATI VGA Wonder with a bus mouse port, I vaguely remember.
Very slow, especially on Windows with VGA driver. But usable for little Windows games, adventures, chess games and Commander Keen.

Grzyb wrote on 2025-08-27, 04:02:

In Poland - only replace the most obsolete component, usually the motherboard+CPU combo.
The 286 boxes from early 90s were still in active service a few years later, but they weren't 286 anymore - they got upgraded.

I'm curious, were these very small Baby AT mainboards common over there, as well, by any chance? 🙂
You know, those compact 386 motherboards with, say, an am386DX-40..? I really liked them! ^^

Jo22 wrote on 2025-08-27, 16:42:

I'm curious, were these very small Baby AT mainboards common over there, as well, by any chance? 🙂
You know, those compact 386 motherboards with, say, an am386DX-40..? I really liked them! ^^

Sure, they were everywhere, usually with late 386SX - see eg. https://th99.infania.net/m/A-B/31008.htm

They were cheap enough for newcomers to not even consider a 286, and the obvious upgrade for those who already had an XT or 286.
They even had certain potential for many years of service: easily accomodated 16 MB of RAM and 528 MB of HDD, which was enough for Windows 95 and even early Linux.
Too slow for Doom and MP3, but those who didn't care about such toys could have used a well-equipped 386 until the XP era.

No offense, but how can you emulate a more advanced CPU on a less advanced one?

Sounds like it would be sluggish and clunky at best.

Peter Swinkels wrote on 2025-08-28, 07:53:

No offense, but how can you emulate a more advanced CPU on a less advanced one?

Hey! 😁 The 286 and 386 are like close brothers/sisters! 😁

IMHO, long story short I think it works via exception handling. 🙂
Emu386 handles the illegal instructions that the 80286 doesn't understand.

It's similarily comparable to how 80286 can handle 8087 emulation in software, perhaps.

The 80286 is an often overlooked CPU in history, I think.
Despite the fact it managed to run Microsoft Xenix, Novell Netware and OS/2 way back in the 1980s.

And Concurrent DOS (and DOS XM) and its siblings! 😁
https://en.wikipedia.org/wiki/MP/M#MP/M-286

Given an external MMU, the 80286 can do fully handle some quite sophisticated OSes, such as PC-MOS/386.

The main limitation is that the 80286 didn't feature paging and mapping/trapping yet.
The 80386 MMU was much more sophisticated here.

But still, with an external hardware (such as a MMU or a few TTL chips),
the 80286 could do some port trapping, too.

Some AT&T/Olivetti PCs did this under Unix,
they had external helper hardware that helped physically trapping calls for the DOS VM.

https://en.wikipedia.org/wiki/Merge_(software)

Peter Swinkels wrote on 2025-08-28, 07:53:

Sounds like it would be sluggish and clunky at best.

Yes and no. Depends, I'd say. 🤷‍♂️

Sometimes it's just one or two 386 instructions that were accidently left in an otherwise plain 8086 or 80286 program.
Emu386 then handles the instructions and the program continues to proceed.

Edit: What’s also notable: The 80286 used to be buggy initially,
but with the last stepping it became a very clean and reliable design.
The 80286 is the kind of CPU that could be entrusted to handle critical infrastructure.

It has a very clear definition of priorities and permissions.

Code segments can be definied as executable/non-executable and it features the Protected-Mode with Ring 0 to 3.
Range of virtual memory can be 1GB, assuming default segment size (64KB, like it's hardcoded on 8086; selectable from 1 to 64KB on 80286).

Unfortunately, Windows 3.x was the most popular environment and didn't take advantage of any of that.
I suppose OS/2 1.3 probably is the only mature 80286 operating system that uses 80286 MMU for virtual memory and the rings of Protected-Mode (0 kernal, 2 graphics, 3 applications)..

Edited.

Can this run on V20, I think it should? I've tried it sometime, but it reported no 286 CPU. Maybe you can byte patch the check also.

On a historical note my country (Cro) is interesting because we had somewhat normal 80s and completely abnormal first half of 90s due to war.

While talking to people from other areas of Europe I can see continental Europe 'lacked' behind USA when it comes to adoption of PC at home, several years at least. In entire Europe it was common to have a "home computer" in 80s at home, not a PC. I would see PCs at homes of people who dealt with PCs professionally. In late 80s people in well off 'western' countries started getting Ataris and Amigas instead of Commodore. Atari ST in itself is interesting because it might seem like a super-duper computer for someone that was stuck on XT in 80s, in reality it is a low cost, cheap hybrid between PC and home computer.

On the other hand, we did not have trade agreements, joint markets, and so on, buying imported computers was always expensive.
People from here used to circumvent that by taking a ride to Italy, Austria, Germany, buying tech there and smuggling it in. Yugoslavia started regulating home and PC market (e.g. inserting models in customs catalogues, forming tariffs etc) in 1983 when it was evident a mass of people already have them.

In USA and some other countries you had a shit ton of vendors selling equipment produced in that territory. You could buy a computer from a mag advert, and in 2 years you could buy expansions for the same computer from the same mag, from the same vendor.

I guess in Europe, especially here, it was harder to get anything so upgrading wasn't in anyone's direct goal. You got it, you use it.

Peter Swinkels wrote on 2025-08-28, 07:53:

No offense, but how can you emulate a more advanced CPU on a less advanced one?

Actually, there's nothing special about it.
General rule is: any Turing-complete machine - with enough memory! - can emulate any other computer.
See eg. normal 32-bit Linux running on 8-bit ATmega1284p, or even on 4-bit Intel 4004:
https://dmitry.gr/?r=05.Projects&proj=07.%20L … nux%20on%208bit
https://dmitry.gr/?r=05.Projects&proj=35.%20Linux4004

Sounds like it would be sluggish and clunky at best.

Sure, the emulation *is* sluggish.
But - as already explained - often there's no need for the emulator to handle every instruction.
There's plenty of "386" software where 99+% of the code is actually 8086/286 instructions, with only sporadic 386 instructions - and that's where Emu386 is useful.
But don't even think about using Emu386 with programs that use extenders like DOS4GW...

In entire Europe it was common to have a "home computer" in 80s at home, not a PC. I would see PCs at homes of people who dealt with PCs professionally.

Hi, I think that's right, but I don't dare to make a definite statement. 😶‍🌫️

I merely know for sure that my father had owned a Schneider PC1512 at the time,
which he soon had a hard card (file card) and V30 bought for.

It appears to me that the Amstrad PC1512/PC1640 were roughly the equivalent to the Tandy 1000 in the US.
- An affordable family and "home office" PC, so to say. Like the Amstrad Mega PC, but in the 80s.

Edit: The Schneider Euro XT was a home computer style PC sold in 1987 or so.
Italy had the Olivetti Prodest PC1, UdSSR had Poisk-1 which emulated CGA in software (!).
There also were Atari PC1 and Commodore PC1, I recall. Both were cute, but low-end desktop PCs (just one floppy, no HDD).
Not sure about actual market shares, though. I just meant to not hide this info.

Atari ST in itself is interesting because it might seem like a super-duper computer for someone that was stuck on XT in 80s,
in reality it is a low cost, cheap hybrid between PC and home computer.

Hi, yes, that's spot on I think.

In my country, the ST was popular as an Macintosh alternative.
Some users even literally ran Mac OS software (System) on it - via Aladin, Spectre and Magic Sac.

We had (almost) no fancy Macintoshs like the US Americans had, but many Atari STs with the SM124 mono monitor.
Calamus and Cubase were overly popular, I think. The Atari ST was the #1 MIDI computer, too.

Can this run on V20, I think it should?
I've tried it sometime, but it reported no 286 CPU. Maybe you can byte patch the check also.

I'm afraid the answer is negative. 😟
The 80186/80188 would been the minimum, I suppose.
Because, the 80186 has a chance to emulate an 8087 via exception handling.

There might be later NEC V series processors that can do it, not sure.
They may need a little adapter board.

On an full-size XT class PC, I think, the easiest solution would be to use an CPU accelerator board.
Often, such a board has an 80286 or 80386 and a socket for the original 8088 (or V20).
By using a toggle switch, both processors can be chosen from before powering the PC on.

Hey Jo22,

Yeah I see history that way too. Every country was engaged in producing school and home computers by late 80s.
I am also not sure about market numbers of domestic computers on the Yugoslav home market. There was a lot of stuff, a lot of companies, in 3 republics, and this actually made a situation for internal market a bit worse because there was no big name to reap the government contracts and grow on that money, like Olivetti in Italy, which was an actor in our market too. Availability of Asian IBM clone gear and local OEM builds did not help either.

So here's a computer - https://en.wikipedia.org/wiki/Lira_512 - actually looks great, I found it on google, never seen it, my school right around those years converted from couple of C64s to a lab of clone-286s with Novell network. This was an excellent school in a major city. Where they were less fortunate - they'd use some old domestic 8 bit micro, a Spectrum clone. And of course vast majority of schools in the country had nothing - a diapositive projector maybe.

Maybe these were used in Serbia regularly, but that shows the over-segmentation of internal market.
The most "popular" domestic computer in Croatia back then was '84 Orao (Eagle) which is like late PET in C64 shape, however it's its own thing and didn't support any prior software, so was used for BASIC @ school mostly.

Jo22 wrote on 2025-08-28, 14:11:

I'm afraid the answer is negative. 😟
The 80186/80188 would been the minimum, I suppose.
Because, the 80186 has a chance to emulate an 8087 via exception handling.

V20 does 186 instructions tho. In this topic CGA versions of 286 EGA/VGA games we talked about those games that need 286 but can run on V20.

Does Emu386 work on V30 and V20 CPUs, 'cause there is a check if CPU is 286 (or newer) and it refuses to load in DOSBox-X in 186 CPU mode? Currently I can't test Emu386 on emulated or real V30 or V20 CPU.

Hi, I could be wrong but I assume that Emu386 involves using that "invalid opcode exception" feature (INT6).

https://www.phatcode.net/res/223/files/html/C … _17/CH17-2.html
Re: Computers based on the 80188 processor

There's a chance the 80186 has it, too.:

"The 80186 introduced an invalid opcode exception (interrupt vector 6, now designated #UD),
which was triggered by attempting to execute an undefined or invalid opcode.
The UD2 instruction is nowadays explicitly reserved to trigger the exception and won’t be reused later,
as is the fate of many formerly invalid instruction sequences."

https://www.os2museum.com/wp/undocumented-8086-opcodes/

Edit: Did some further research.

"7) Then Invalid Opcode NEC/Sony V40/V50 do INT 6
NEC/Sony V20/V30 don't."
Source: https://fd.lod.bz/rbil/opcode/other.html

"V40/V50 'H' version is slightly more capable. It has two subsets of DMA controller chips built in.
One of them is uPD71037, which seems to be compatible with the Intel 8237.
What's more, the 'H' version also has four index registers that can be mapped to the correct IO addresses."
Source: https://forum.vcfed.org/index.php?threads/hel … 4/#post-1428020

Jo22 wrote on 2025-08-30, 10:37:

Hi, I could be wrong but I assume that Emu386 involves using that "invalid opcode exception" feature (INT6). […]
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Hi, I could be wrong but I assume that Emu386 involves using that "invalid opcode exception" feature (INT6).

https://www.phatcode.net/res/223/files/html/C … _17/CH17-2.html
Re: Computers based on the 80188 processor

There's a chance the 80186 has it, too.:

"The 80186 introduced an invalid opcode exception (interrupt vector 6, now designated #UD),
which was triggered by attempting to execute an undefined or invalid opcode.
The UD2 instruction is nowadays explicitly reserved to trigger the exception and won’t be reused later,
as is the fate of many formerly invalid instruction sequences."

https://www.os2museum.com/wp/undocumented-8086-opcodes/

Hi, Jo22!

Or maybe 186 emulation in DOSBox-X is not 100% correct.

I'm asking, if someone tried Emu386 on a real XT system with V20/30 CPU, 'cause there's string "PC/AT with 80186/80286 processor required" in Emu386 executable (V20/30 and 186 CPUs have 286 real mode instructions, right?) and I got it when I tried this "386 for 286" emulator in DOSBox-X with 186 CPU (the closest thing to V20/30) emulated. With DOSBox-X 286 emulation Emu386 works as expected. I'm curious, if this message will pop-up on a real V20/30 CPU i.e. if Emu386 can be used in systems with V20/30 CPUs.