Disruptor wrote on 2023-11-28, 01:39:

But not IBM-compatiblity. […]
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kant explain wrote on 2023-11-28, 00:20:

Jo22 wrote on 2018-09-22, 09:51:

That's right. Though IBM PC compatibilty wasn't all that important in the first half of the 1980s. Originally, system makers ass […]
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That's right. Though IBM PC compatibilty wasn't all that important in the first half of the 1980s.
Originally, system makers assumed that industry kept going the CP/M way of hardware independence,
so MS-DOS compatibility was considered good enough for a while. Unfortunately, things went different and programmers started to
do a lot of bare metal programming, assuming everyone had an IBM PC. This broke compatibility for a lot of early systems,
which were only DOS and partially PC-BIOS compatible. Anyway, I'm no PC/XT expert. Just summing up what I learned from reading old magazines.

🤣 lOL compatibility was extremely important in every part of the 80s (except 1980, non IBM puters were all the rage). Thing is if you bought a Tandy 2000 say, and had a few dozen titles to choose from, you maybe were fat (as was I), dumb (as I was definitely), and happy for a while. Until you tried to boot Starflight 🙁. A lot of hot titles were available. There's a sourceforge or github site full of Tandy 2000 specific s/w and docs if you google.

But not IBM-compatiblity.

CP/M compatiblity was the thing in the low 1980's.
Even MS-DOS had to be kinda compatible to CP/M (because 86-DOS/QDOS was inspired by CP/M's API).
Later it was DOS compatiblity. Microsoft supplied adaptions for almost each supplier within DOS 1.x, like PC-DOS.
Suddenly the IBM PC got mainstream (perhaps due to the royalty-free PC-BUS "ISA") and things changed. While the compatiblity to the IBM PC got important, Phoenix developed a BIOS that was free from any IBM code but has cloned the interface and Microsofts sold its own MS-DOS to the users of the clones. That was likely in the mid of the 1980's.
But even the API of MS-DOS has been changed. Do you remember accessing files with FCBS?
With the IBM AT in the mid 1980's it was still IBM who set the standard. However, with the 386 IBM lost the lead... to a "COMPAtible Quality" manufacturer.

MS-DOS was kinda cp/m compatible from the getgo. That's where they got the 8.3 file naming convention. Cp/m was a thing, but there were clones in 1982. Not many at all had anything other then dos as an option, at least not advertised.Microsoft wrote PC/MS-DOS. They were offering it with the Columbia, Compaq, etc. Most of the pseudo compatibles came out in 1983. The Tandy 1000 by 1984. Not exactly sure when the big apps were released, lotus, ashton tate, various M$ titles. But companies weren't building outright clones or something less so peeps could run cp/m.

I don't even know what fcbs is. I'm not aware of the bios changing significantly, as they were in firmware. The dos functions, which were disk based were updated from version to version somewhat. You can format and copy floppies easily with bios code alone.

You can talk about alternate os' for the pc, p-system, netwate-86, etc. and they're all interesting. But the pc was a hit a) because huge company built it. And b) it seemed to make more sense to write for dos.
Cp/m-86 is basically just a footnote. Why exactly I don't know.

And you have to remember all the clones ran ms-dos. Some had their own versions. Those that required anything other then vanilla dos and couldn't run off the shelf ibm stuff were doomed. People bought them. But too few to make any a hit. And none were able to take the reigns from IBM. Despite most if not all being superior technologically.

1982 Canon AS-100 ad

https://www.ebay.com/itm/114943214791

Cp/m-86 advertised as an option. I have 2 of these, but no os disks that work anymore. It's a weirdo. You had to buy blank floppies from Canon, they had.to urinate on them before use. Got to break 1 out soon.

Another obscure 80186 based system is the 80s Swedish school computer Compis.

It's very much a product of its time. The politicians and state, led by the social democrats more or less uninterrupted since 40 years back then, of course knew best what the kids needed for their education, and ordered this huge and expensive project developing a computer system from scratch instead of buying something from the commercial market. The resulting product was of course completely obsolete and irrelevant from the beginning, something of a joke to anyone who had a PC or similar at home. The public schools were more or less forced to buy it, despite knowing this.

It ran CP/M-86 with a custom menu system from ROM. It was also possible to boot an early version of MS-DOS from floppy. Would guess it was an afterthought, when they realized this was what's used in the real world. The good things about the Compis was the multitude of ports giving great possibilities for networking and connecting peripherals, and the graphics, that were very competent for its time.

Also loved the highly qualitative keyboard, I believe it used buckling spring switches. The key travel was quite short, just as I like it. The delete key, marked "UTPLÅNA", became something of a legend. While "utplåna" technically could be a correct translation of "delete", it's much more severe. I'd translate it back to "obliterate".

I belonged to the last age group using Compis in the mid 90s. They were replaced in my secondary school the summer after I finished. Remember being royally pissed off my kid brother got to use their brand new 486:s when he started the same autumn. Nowadays I'm instead very happy I got to experience this piece of computer history in first person before it was too late.

I'd love to have one, but regrettably those computers are very rare nowadays. Would guess most of them ended up collecting dust in school basements after being replaced, before being scrapped in one go when it was decided the space was needed for something else. They were also never sold to the public, very few of them reached the second hand marked even back then.

If I get my hands on one at some point, it would be interesting to see if it's possible to load MS/DOS from ROM too. Maybe even build some custom PCB to be able to switch between ROMs and OSes.

A Compis in all its glory, with dual floppy drive, monitor and keyboard. The latter is supposed to be connected to the "Tangentbord" port in the front, there's no connector in the rear IIRC. The box to the right is a HDD cabinet, that could be accessed over the network.

Some links:

https://en.wikipedia.org/wiki/Compis
https://www.old-computers.com/museum/computer.asp?c=358
http://www.datormuseum.se/computers/others/te … ova-compis.html
https://www.pugo.org/collection/computer/167/

kant explain wrote on 2023-11-28, 00:57:

Who knows. The 80188 is available in abundance on ebay rigjt now. I bought a batch from this vendor andnmay buy more. If anyone needs help obtaining these message me.

Don't expect too much of the 80188 regarding performance. The 80188 does in fact have a vastly improved execution unit (mostly identical to the 286 execution unit, AFAIK) that can execute instructions considerably faster than the 8088. On the other hand, the 80188 has the same bus interface unit as the 8088, so it is still limited to one bytes per 4 clocks. It is well known that the 8088 is starving on fetching opcodes a lot of times (the Intel data sheet already warns that the 8088 might starve on fetching opcodes, and execution time might exceed what you get from adding "execution times"). The 80188 is nearly always starved on fetching opcodes (the situation is that bad that even the vendor didn't dare to play it down. The datasheet of the 80188 explicitly mentions the risk that the instruction prefetch queue is not sufficiently filled most of the time). The 80188 has several advantages over the 80188, but they didn't really matter when trying to build an improved PC/XT clone.

• The 80188 can execute the new high-level language support instructions like ENTER, LEAVE, allowing shorter (and faster to fetch) procedure prologue/epilogue code sequences. This advantage is useless if you run software compiled for the 8088.
• The 80188 can execute the new "push immediate" instruction allowing shorter (and faster to fetch) parameter passing sequences for constant parameters in high-level languages. Again, this is irrelevant if you run software compiled for the 8088.
• The 80188 can execute shift and rotate with a fixed shift/rotation count other than 1, allowing shorter (and faster to fetch) code sequences for shifting/rotating values. As this feature was not present on the 8088, this feature will not be used by PC/XT software.
• The 80188 contains an integrated timer, interrupt controller and I/O decoder. These peripherals are designed to suit a 16-bit system (whereas the 8253 and 8259 found in the IBM PC were designed to suit 8-bit systems). These peripherals are mostly useless in PC/XT clones, but they successfully positioned the 80188 into the "embedded controller" market, competing with Z80-derived microcontrollers.
• As discussed, the 80188 has a new execution engine, and it will surely beat the 8088 execution engine on the "signature slow" instructions of the 8088 like DIV, but due to the bus bottleneck, it is not a significant win otherwise.

In hindsight, the ability of the 80188 to execute DOS software targeting the 286 instruction set seems like a big win to enhance compatiblity of an old machine (just as the V20 does), but at the time that 80188 based PC clones could have been designed, there was no 286-targetting DOS software yet. There also is a disadvantage of using the 80188 in a "classic PC" design: The 8088 uses the very common DIP40 package, which allows cheaper manufacturing than the newer PLCC or PGA packages the 80188 used.

While this post was mostly pointing out why the 80188 was not considered useful for PCs, the "speed" point is not that bad for the 80186: The 80186 uses 16-bit access to fetch instructions, doubling the bandwidth. This makes the execution engine only "sometimes stalled" instead of "nearly always stalled". All other considerations apply to the 80186 just as they apply to the 80188. And when you consider building a 80186-based 16-bit computer, the 80286 is a really strong competitor: It again doubles the memory bandwidth (at "0WS", an 8086 takes 4 clocks per memory cycle, while an 80286 takes just 2 clocks per memory cycle), and increases the amount of easily addressible memory, allowing "the operating systems of the future, like OS/2" to run, whereas the 80186 was seen as a dead end in PC architecture as soon as the AT-type designs started to take off. The low-end market was perfectly served by 10MHz Turbo-XT clones, and the high-end market got their 286 machines.

mkarcher wrote on 2023-11-28, 11:08:

(just as the V20 does)

The NEC V20 (and its 8086-equivalent V30) seems to be what you'd actually want:
You get a chip that is pin-compatible with the 8088 (or 8086), so it is a drop-in replacement in a standard PC/XT motherboard, and it gives you the added 186 instructionset and better performance.
The integrated parts of the 188/186 aren't interesting for a PC clone, because they aren't compatible in any way.

It might be interesting to make an new 8086 motherboard with true zero wait states 16-bit memory and 16-bit ISA slots. I found something similar here https://github.com/rodneyknaap/atx-turboxt-v3 but it turned out that the system, despite the 8086 processor, is 8-bit, and the ISA slots also use only 8-bit.
History knows computers with an 8086 processor, but 8086 computers with a 16-bit ISA - perhaps I know only one such example - is the Robotron EC-1834 computer, with non-standard expansion slots and quite narrowly known in countries other than Germany and the exUSSR.
Sometimes I even think about creating a brand new mini-ATX board with 8086 and ISA-16 -)

I don't care about any of that. I think the 80188/86 is damned cool like the OP and that's what I want. Not do the same old shit...8088..8086..v20/30/40. It's been done oi!

Don't talk to me about Robotrons. I get swets just thinking about it. I used to be an arcade Robotron champion. The swet would roll off of me.

Ok that github atx board is very cool. Reminds me of the MPX-16. Which was a dud but is wonderful nowadays as collectible curio junk 🤣

kaputnik wrote on 2023-11-28, 10:52:

Another obscure 80186 based system is the 80s Swedish school computer Compis. […]
Show full quote

Another obscure 80186 based system is the 80s Swedish school computer Compis.

It's very much a product of its time. The politicians and state, led by the social democrats more or less uninterrupted since 40 years back then, of course knew best what the kids needed for their education, and ordered this huge and expensive project developing a computer system from scratch instead of buying something from the commercial market. The resulting product was of course completely obsolete and irrelevant from the beginning, something of a joke to anyone who had a PC or similar at home. The public schools were more or less forced to buy it, despite knowing this.

It ran CP/M-86 with a custom menu system from ROM. It was also possible to boot an early version of MS-DOS from floppy. Would guess it was an afterthought, when they realized this was what's used in the real world. The good things about the Compis was the multitude of ports giving great possibilities for networking and connecting peripherals, and the graphics, that were very competent for its time.

Also loved the highly qualitative keyboard, I believe it used buckling spring switches. The key travel was quite short, just as I like it. The delete key, marked "UTPLÅNA", became something of a legend. While "utplåna" technically could be a correct translation of "delete", it's much more severe. I'd translate it back to "obliterate".

I belonged to the last age group using Compis in the mid 90s. They were replaced in my secondary school the summer after I finished. Remember being royally pissed off my kid brother got to use their brand new 486:s when he started the same autumn. Nowadays I'm instead very happy I got to experience this piece of computer history in first person before it was too late.

I'd love to have one, but regrettably those computers are very rare nowadays. Would guess most of them ended up collecting dust in school basements after being replaced, before being scrapped in one go when it was decided the space was needed for something else. They were also never sold to the public, very few of them reached the second hand marked even back then.

If I get my hands on one at some point, it would be interesting to see if it's possible to load MS/DOS from ROM too. Maybe even build some custom PCB to be able to switch between ROMs and OSes.

A Compis in all its glory, with dual floppy drive, monitor and keyboard. The latter is supposed to be connected to the "Tangentbord" port in the front, there's no connector in the rear IIRC. The box to the right is a HDD cabinet, that could be accessed over the network.

Some links:

https://en.wikipedia.org/wiki/Compis
https://www.old-computers.com/museum/computer.asp?c=358
http://www.datormuseum.se/computers/others/te … ova-compis.html
https://www.pugo.org/collection/computer/167/

That's pretty svelte. Too bad it was such a drain on the economy. And a blight on the education of young Swedes.

Did anyone mentioned the RM Nimbus?

https://en.m.wikipedia.org/wiki/RM_Nimbus

kwyjibo wrote on 2023-11-28, 21:55:

Did anyone mentioned the RM Nimbus?

https://en.m.wikipedia.org/wiki/RM_Nimbus

That one is cool, it had networking and good graphics!
It had used Windows 1.x and 2.x, too, before it was popular.
Too bad it was not available outside the UK.

Source: https://www.thenimbus.co.uk/

Btw, the BBC Master 512 had used an 80186, as well.
And it ran DOS Plus and GEM. It even had a mouse (available under GEM).
CGA was software emulation, but worked acceptable if it worked.

Pictures: Re: PC compatibility cards

The Nimbus was indeed available outside the UK thanks to the innovation known as air mail.

I actually only had the motherboard. I wound up selling it to someone in Sweden. That someone probably disillusioned due to the Compis. We never exchanged woes. But I felt in my heart the mobo took flight and was received to a good and grateful home.

The Nimbus was kind of a British Tandy 2000. More sensibly designed in some respects. But, and correct me if I'm wrong, it didn't sport 400 lines in color. Maybe in monochrome but maybe not at all. Someone had 1 for me. I never took delivery.

Inside the IBM PC by Peter Norton. A MUST read. There are 2 editions to my knowledge (prior to the PS\2 line). The 2nd or subsequent edition says "Revised and Expanded". I want to say you need both, as there is material in the 1st edition that isn't in the "revised". I'm not positive though. I currently habe the newer 1, and I think I am going to reread it. Mayne then decide if the earlier edition needs goimg over again.

Again a must read and a precursor to deeper study into 80x86 systems.

Any good books of a similar vein does anyone want to recommend? I'll add more over time.

Don't pay Amazon prices. Check poopBay or get it through an interlibrary loan.

kant explain wrote on 2023-11-28, 21:04:

kaputnik wrote on 2023-11-28, 10:52:

Another obscure 80186 based system is the 80s Swedish school computer Compis. […]
Show full quote

Another obscure 80186 based system is the 80s Swedish school computer Compis.

It's very much a product of its time. The politicians and state, led by the social democrats more or less uninterrupted since 40 years back then, of course knew best what the kids needed for their education, and ordered this huge and expensive project developing a computer system from scratch instead of buying something from the commercial market. The resulting product was of course completely obsolete and irrelevant from the beginning, something of a joke to anyone who had a PC or similar at home. The public schools were more or less forced to buy it, despite knowing this.

It ran CP/M-86 with a custom menu system from ROM. It was also possible to boot an early version of MS-DOS from floppy. Would guess it was an afterthought, when they realized this was what's used in the real world. The good things about the Compis was the multitude of ports giving great possibilities for networking and connecting peripherals, and the graphics, that were very competent for its time.

Also loved the highly qualitative keyboard, I believe it used buckling spring switches. The key travel was quite short, just as I like it. The delete key, marked "UTPLÅNA", became something of a legend. While "utplåna" technically could be a correct translation of "delete", it's much more severe. I'd translate it back to "obliterate".

I belonged to the last age group using Compis in the mid 90s. They were replaced in my secondary school the summer after I finished. Remember being royally pissed off my kid brother got to use their brand new 486:s when he started the same autumn. Nowadays I'm instead very happy I got to experience this piece of computer history in first person before it was too late.

I'd love to have one, but regrettably those computers are very rare nowadays. Would guess most of them ended up collecting dust in school basements after being replaced, before being scrapped in one go when it was decided the space was needed for something else. They were also never sold to the public, very few of them reached the second hand marked even back then.

If I get my hands on one at some point, it would be interesting to see if it's possible to load MS/DOS from ROM too. Maybe even build some custom PCB to be able to switch between ROMs and OSes.

A Compis in all its glory, with dual floppy drive, monitor and keyboard. The latter is supposed to be connected to the "Tangentbord" port in the front, there's no connector in the rear IIRC. The box to the right is a HDD cabinet, that could be accessed over the network.

Some links:

https://en.wikipedia.org/wiki/Compis
https://www.old-computers.com/museum/computer.asp?c=358
http://www.datormuseum.se/computers/others/te … ova-compis.html
https://www.pugo.org/collection/computer/167/

That's pretty svelte. Too bad it was such a drain on the economy. And a blight on the education of young Swedes.

Yeah, I also like its compact minimalist design. Looks very professional. Might have chosen other colors for it, but hey, it's far from the only brown computer of its time 😁 My favorite part of it, the keyboard, uses some kind of serial protocol. Should be easy enough to build a USB adapter from a RPi Pico and use it with a modern computer if I ever get my hands on one.

Well, in its defense, when it was implemented in the public schools, almost no one had a computer at home. I was one of the lucky few, mostly due to my father working with technical development in the mining industry then, realizing that computers were the future. He insisted on me and my brother learning to at least use them from an early age, and made sure we had the means to. For the kids that didn't, I guess the Compis still was way better than nothing.

When it comes to crazy projects draining the economy, have a look at the Swedish cold war jet fighters. The Compis project was a piss in Mississippi in comparison 😁

It's also interesting how the state awarded a fledgling company with no practical experience of developing a computer system the project, when Ericsson and Luxor, that both had numerous successful business models in their portfolios, were just around the corner.

I will hear no more of this. The Compis had an 80186 and therefore is a bad-ass contraption!

I'd advise you never to piss in the Mississippi. Loaded with snapper turtles and water moccassins. They bite you on yer bum and kill you.

Yeah, someone at Compis llc. was spending time in a particularly uncomfortable orientattion. In good taste, or bad taste yuk, I'll leave that to everyone's imagination.

So ... SMC wasn't as obscure a chip maker as I thought. The Compucolor II used SMC chips.for graphics. Learning something new everyday.

kant explain wrote on 2023-11-28, 09:50:

Not exactly sure when the big apps were released, lotus, ashton tate, various M$ titles. But companies weren't building outright clones or something less so peeps could run cp/m.

They were actually the Johnny come latelys what we think of as the big DOS apps now, because they were the late 80s survivors. The big apps at the time carried over from CP/M Wordstar and VisiCalc etc, they were initially successful on DOS but somehow blew what seemed an unassailable lead by various forms of arrogance, bloat, corporate malfeasance and internal politics leaving the the upstarts to claim the field.

Yes WS and VC were mega apps in their day. And ran on mulriple platforms. They must have been popular on the PC. But I suspect the big dos apps sold way more.

I have to add a link to a Nokia PC brochure from the -80:s, it was using a 80186 too, and we had a number of these where I worked at the time.
Nice machines & easy to read text on, but the monochrome white-phosphor screens tended to burn in the images fast, unless turned off.

https://www.net.fujitsu.fi/fi/historia/mikrot … al_computer.pdf

Disruptor wrote on 2023-11-28, 01:43:

kant explain wrote on 2023-11-28, 00:52:

aquishix wrote on 2018-09-23, 15:04:

http://www.vcfed.org/forum/showthread.php?282 … odesl-25-amp-30

Link don't work.

That's the problem with the internet and referring to a 5 year old thread.
Links may get invalid if the webmaster did not care about compatiblity.

I think the problem is with this site. It seems to have crunched the link rendering it unusable.

kant explain wrote on 2023-12-02, 04:50:

So ... SMC wasn't as obscure a chip maker as I thought. The Compucolor II used SMC chips.for graphics. Learning something new everyday.

SMC, or Standard Microsystems Company was based in New York, and made various chips for microsystems (obviously) before finally specializing in networking.
In the 80s and early 90s it wasn't that uncommon to find SMC chips on PC clone motherboards, multi IO cards and especially network cards.