Category Archives: IBM

32bits of disappointment, upgrading the IBM PS/2 model 60

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So long..

While I had enjoyed this fully loaded 286, it was getting a bit annoying with all the 32bit limitations I was running into. Frontier Elite was a 32bit program, Obviously no WIndows/386 nor any DooM. It seems that most of the MS-DOS fun I had really was 32bit only. So with this PS/2 model 60, I did the only real thing I could do:

PS/2 80 motherboard

I swapped the motherboard with a PS/2 model 80 board. I had seen this on eBay for a bit of an excessive price, offered 40% of said price, and woke up to having shockingly won the bid. Of course it also means that I need special 32bit RAM to boot the board, because “IBM”.

a 1MB module

I picked up 2 of these 1MB modules, they are 3 chip much like the SIMMS I had used on the PS/2 model 60 motherboard. So these are no doubt parity 256k in each row, and 2 cards giving it 2MB of RAM right off the bat. I got lucky to find these 2 cards in country and at a really reasonable rate, when compared to all the others. They did make 4MB & 8MB cards, but naturally they are incredibly expensive.

Bootup

Luckily for me the board & RAM worked (the board was listed as working), and running setup from the gotek was painless. However for the heck of it, I put in the Boca RAM/2 board to see if it works. It does. It also does the same thing where once the Boca RAM/2 board is configured the setup program only crashes on running it, meaning I need to disconnect the battery backed RAM.

I thought I could avoid setting up the RAM card, but oddly enough until I did so it would not initialize the SCSI card. Oh, sure it showed up in the setup program, saw all my disks and everything, but it would not boot or show up from a boot disk.

So now let’s re-visit the painful world of SCSI disks. I had bought one SCSI controller, and tore some pads off for being impatient, bought another and had it working fine with the approved cable, crashed the PS/2 MCA SCSI market, and then bought the caching faster controller card, to only reveal that it is in fact slower than the stupid card.

But it’s a 32bit card!

And now I have 32bit slots and a 32bit processor! Surely it’s going to ROCK!!!!….?

32bits of disappointment

It’s 0.3% faster.

What the actual FUCK. I mean ok BlueSCSI is great, and we’ve seen it perform faster with the ‘stupid’ card. I can’t imagine paying the $999 MSRP of this faster caching card to find out its slower. Nor the massive upgrade cost of going 32bit to find out its only slightly faster.

Wow.

Just Wow.

LANDMARK 6.00

That said, v86 mode is really cool!

My goto test for v86 is BattleTech the crescent hawk’s inception. I mean if Windows/386 can run this, everything else should be able to. And yeah, 16Mhz is almost enough to run this in a window. It screen tears like crazy and is just slow. But at least it runs!

Warning beeper music!

Although football was capable of doing this full screen in 1987, and Windows/386 could run it in a window in 1987 as well, it wasn’t until 1989/90 that OS/2 could with the much delayed 32bit version. Of course, the divorce happened after Windows 3.0 became such a massive seller, and OS/2 was delayed. again. While I had no issues under 86Box, I had plenty of weird issues on real hardware that seem to magically sort themselves out by running Infocom’s Planetfall first. I don’t know why either.

16Mhz Wing Commander

And luckily there is some difference in running at 16Mhz. Although I haven’t tried EMM386 on/off yet. The 286 had it’s excuse of copying pages in & out of protected mode, and the switch time being so horrific. But the 386 should be instant, only limited by it’s slow bus and I guess 4MB of slow RAM.

But what about DooM?

DooM v1.1 low resolution not quite postage stamp sized

Yes DooM v1.1 runs! I’ll have to try some Fast DooM later to see how much faster it can be! I’d like to think itll be faster but I am not holding out much hope.

Many of the bench stuff I had setup on the 286 to compare to the 386 sadly depend on a math processor. The problem of course is that 80287’s are very cheap for some reason. 80387’s however are not.

eBay special

And the majority of them look like this. I don’t know how on earth people have hundreds of 80287’s to sell at super cheap prices, but 80387’s all seem to have been trampled, or had their inner core’s turned into slag. I will keep a lookout, although knowing my luck it may be cheaper to find another motherboard with a 386/387 paring.

Speaking of OS/2 and weird crashes, I got this fun one from OS/2 trying to run sysinfo:

trap 000e on 038600b1

While I’d seen plenty of trapcodes in my time, but I know less than nothing about reading them. Maybe it’s burred in there somewhere. The one odd thing was the 038600b1 part… Since the 386 is a 16Mhz part, maybe it’s a crazy old version? While it does have the ΣΣ mark, maybe there is other troublesome 386’s? I really don’t know. Or maybe OS/2 is just really more sensitive to having 2MB 32bit RAM + 4MB 16bit RAM.

Way back in the old times, I had upgraded from a 12Mhz 286 to a 16Mhz 286, and life was great, although I left out of all the 32bit personal computer revolution. After a lot of hard work, I managed to secure a 386sx 16Mhz board with 4MB of RAM. It was awesome although yeah SLOW. Clock for clock, task for task the 386sx was at best the same speed. Sometimes I’d swear the 286 was faster. A few months later though I made the insane trade of some complete in box Infocom games, along with cash and was able to score a 386DX 16Mhz, along with 4MB of 32bit RAM on some massive board. Surely this was going to be great right? I found pretty much the same thing there was no perceivable difference at all. At least back then it was 1992? and the capacitor plague was still decades away, and you could just call the BBS of the motherboard vendor and download the disks if needed (I didn’t need to). It was, frankly, a big letdown after so much ’32/32 is far superior to 32/16′ and here we are again in the future and the SCSI card bears it out, that id basically didn’t matter.

I guess it really comes as no surprise that the 386 does everything the 286 can just better.

So, what have we learned? The PS/2 model 60/80 chassis is the exact same thing. The low clocked 386 chips are super unimpressive, no doubt the magic in the intel family really didn’t hit until the DX2/66 and beyond. Beta versions of software act weird, oh, and that the backup program from MS-DOS 5.00 can actually backup a dual booted OS/2 install & restore it just fine. That was a bigger surprise for me, as the great thing about the BlueSCSI i that I can have so many drives, so I made a backup of the C: OS drive and trashed it quite a bit. Not expecting anything, but yes, a restore actually worked.

More PS/2 upgrades! More RAM, More advanced SCSI!

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So I had gotten this Boca Ram/2 card with 2MB of RAM, with space for an additional 6MB. Unfortunately trying to find matching memory has been a lost cause. Since the existing memory is 9 chip modules, I take that to mean it’s parity RAM, so I went shopping for much more available 3 chip modules.

2MB!

I picked up 2x 1MB modules for £10.

Slotting them carefully into the ram card, taking great care as the clips are plastic!

4MB of ram slotted, made in the USA!

Now from what I can remember being told is to never ever ever mix memory types like this. But logically I have to think that 9×1 = 4+4+1, right? RIGHT?!

I copied the @7A7A.ADF onto the reference disk image, slotted the card and booted up to the config, and toggled the card to 4M

4M (4 SIMM modules)

I didn’t trust the auto-config, plus I just wanted to see what was there. Also I’ve always wondered if the PS/2 model 60 (or 30? 50z?) can slot higher density than the 256kb SIMM’s that IBM had used. I guess one day I’ll give it a shot.

Anyways thinking that this is about done, I save the config and reboot and now It’s Bocaram/2 issues.

Immediately, on reboot I get error 164.

164 POST detected a base memory or extended memory size mismatch error.

1. Run F1 Setup. Check System Summary menu for memory size change.
2. Run the Extended Memory Diagnostic tests.

IBM

Great.

Booting from the reference disk just crashes the PC.

Fantastic.

Pressing F1 however does let you boot, ignoring the issue.

After a bunch of digging I found this zip file with some utils. And just guessing br2pmems ‘fixes’ the CMOS settings allowing the machine to boot normally.

So now it’ll recognize the 5MB of RAM, and just boot normally. GREAT. But booting the reference disk still hangs the machine.

Which then brings me to the next upgrade:

The IBM SCSI with Cache

The IBM SCSI with Cache aka the SPOCK. Since I ruined the one SCSI card, and ended up picking up a second card, but this time with the appropriate cable I’ve caused a massive market panic on Microchannel SCSI cards. Seriously check eBay, and you will see that the pricing has collapsed with many now selling in the £20-30 range. You’re welcome!

Not really wanting a 3rd SCSI card, but my eye saw this one with the cache RAM, and I figured if I wanted the ultimate PS/2 of course I’d want a caching controller. This looks to be the first rev of the PCB, but with the ‘hot fixes’ in place from the second rev. While the ROMs are stepping back to 1990, I don’t care much about the 1GB disk limit, as the BlueSCSI can emulate all the available devices in the chain, so I’m not losing anything in the way of capacity. This is a 286 after all.

Since the RAM card screws up the setup program, I have to remove it, and the old SCSI controller, re-configure the system with all the RAM and disks removed first. Then put in the new controller, and re-run setup.

I just accept the defaults, and reboot to check what happened. So far it looks good, slot 8 being near the middle of the PCB, and closer to the disk cage where the blue SCSI rests.

placehold all the drives!

Remembering that the IBM controllers inventory the disks backwards, the 380MB disk image on SCSI ID 6, is the primary boot disk. I didn’t set it to the full 1GB as I want to later see how older versions of DOS/OS2 work with this, and I know they have issues with disks bigger than 512MB, but I figured matching a disk that did exist in 1988 would be more realistic.

With the SCSI setup, I could put the troublesome Boca board back with the RAM, and get my system booting up with the new “faster” SCSI controller, and all that new RAM.

Old SCSI controller

Of course I did a few benchmarks on the old SCSI controller so I would know how much more awesome the new one is.

As you can see this is booted with my normal config.sys with a himem.sys and smartdrv from Windows 3.1 on a MS-DOS 5.1 install.

2,345.8 KB/sec With himem.sys & smartdrv
2,347.5 KB/sec with no himem.sys
2,316.6 KB/sec with runtime xmsmmgr & smartdrv
2,334.0 KB/sec with Windows 3.1 himem.sys no smartdrv

So, with these scores in hand, you can see that the penalty for various XMS memory access being turned on is there, but it’s nowhere near as massive as I’d have thought for performance. Even with it just being there, although again it’s so minimal.

Now for the real shocker:

2,079.2 KB/Sec

That’s right, the advanced card is slower. A good 11% slower. Well, that was disappointing. I’m still keeping it in the machine, as having a hardware caching controller was all the rage, just like Mach microkernels. Maybe it’d make more of a difference in a 32bit system, but it’s performance is very underwhelming. For anyone wondering, the WDC AC2340, is an EIDE 340MB hard disk, with a 64kb cache. Im sure it was considered very fancy, and fast for the era, and it’s nice to know that no matter the SCSI controller, the BlueSCSI blows it out of the water. Also keeping in mind that MFM data transfers are usually sub 400KB/sec, so this is much more faster.

Okay you have all this XMS what are you going to do with it?

Well, after I did manage to get this original copy of Word for Windows 1.0, I thought that it would be a good test. One fun thing is that it includes the ‘runtime’ version of Windows 2.11, which can also upgrade an existing install of Windows 2 if detected. Running Windows 2 on MS-DOS 5, does involve loading the setver command in the config.sys, and rebooting. Windows 2 cannot use XMS (more on that) but instead uses the older LIM EMS standard that allows a 64kb page to be viewed from a far larger card. Since the 8086/80286 still use 64kb segments it’s not all that crazy to use.

And that brings me to this great program EMM286!

It allocates a 64kb page in low ROM, and backfills it from XMS. So I give it 3MB, and now I have 1.3MB of XMS left, and 3MB of LIM EMS ready for Windows!

So now I have EMS & XMS! And didn’t have to get some pesky EMS board either. I am pretty sure you need device drivers to use EMS, so how do you use LIM EMS under OS/2 1.x? I have no idea. Probably not I guess?

Anyways I run word, everything is great, it sees extra ram. I exit windows, and unload EMM286, and ..

3.4MB of XMS available? Somehow I lost a megabyte of RAM from Windows 2?! I’m not sure what is going on, or why or how Windows even touched it. Needless to say if you want it back, you need to reboot.

DOS 10.21
494KB free!

That’s right 494KB free! I thought MS-DOS under OS/2 just used some stubs in real mode, and called back to protected mode. No doubt this is totally wrong, there has to be some weird version of DOS+OS2 that actually runs in real mode going on here. I know that ‘bimodal drivers’ were a thing, but it sure seems like there really is a ‘real mode OS/2’ kernel with MS-DOS tacked onto the side.

Windows 3.0 standard mode, 286 + 5MB of RAM

It’s annoying OS/2 can’t tell you how much ram it sees and what is in use, but at least Windows 3.0 can. It’s more than enough to run Sim City, clearly making this one of the more expensive machines to run the game as intended. With the added RAM it doesn’t thrash as hard, but having emulated disks probably doesn’t matter as much as access time is always zero, and it’ll stream data as fast as it can. You can feel the difference moving between tasks, but things like the OS/2 file manager that loads a view into every directory is still incredibly slow. What were they thinking?!

Thouhts?

Back in the day this would have been an incredibly expensive upgrade. And is it worth it? The machine is still locked at 10Mhz. The FPU is also locked at 10Mhz, and you can feel it. The lightening fast disk access, despite it being some 11% slower is really hard to tell. Does the caching help at all? Applications don’t have to page in/out like crazy before as there is enough RAM to actually run them, but that is where the 10Mhz processor just isn’t there.

Just like the caching SCSI controller, I’m sure we’ve all heard how having that magical EMS memory would help out games like Wing Commander.

XMS/DOS High + EMM286 on the left, and just XMS + DOS High on the right

Well, I had to put them side by side, as I couldn’t believe it, but adding EMS made it noticeably slower. I was *NOT* expecting that. I should add that I used Vegas & this quick tutorial, on how to pan & resize one video to get them side by side. No doubt it’s not perfect but it’s enough to see that once the ship explodes, the performance on the EMS configuration is greatly throttled. It’s moments like this that makes me wonder is this something the caching SCSI card would do better implicitly? Or is it snake oil as well?

3MB is enough to load OS/2, and one application, just as Word v1 or Excel v2/v3 load just fine, but swapping between them is basically unloading one from memory, and loading the other back out to disk. It’s a shame RAM cost so much 1987-1992 as people really could have benefited from it. It’s just utterly bizarre that on such an outrageously expensive system that you even need RAM upgrade cards, it really should have been baked into the main logic board.

Installing the IBM SCSI / A ‘tribble’ card in an IBM PS/2 model 60, using BlueSCSI, and a tale of painful lessons.

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As a follow up to Installing a Gotek floppy emulator, this time I’m adding something desperately needed, mass storage using a SCSI card.

IBM SCSI / A adapter
IBM SCSI / A adapter

The machine is the 40Mb MFM based model, the cheapest option of getting a PS/2 model 60 back in the day. MFM hard disks are incredibly old, and sadly the eventual end point for these old disks is death. While I had investigated a MFM disk emulator they are very costly, with prices starting at $299 USD. Ouch. However, from my Dec Alpha experiments I do have the BlueSCSI was available for a more reasonable £52. So all I would need was a SCSI adapter, and I’d be good to go, right? Mostly.

Looking at the card, you can see that it doesn’t use a standard 50 pin connector. I guess it being the 1980s and IBM trying to re-capture the PC market by going all in with proprietary connectors, they used a 50 pin IDC connector to attach the 50pin SCSI ribbon cable. This would prove to be disastrous for me later on. I initially had no luck finding an original cable, while the SCSI cards themselves seem to be plentiful on eBay. I guess me buying 2 of them has triggered a lot of movement in the market. Another source of concern is that the 286 is 16bit, and the card is advertised as being 32bit, but rest assured the notched middle part seems to indicate that the card is 32bit/16bit compatible. I can attest it works in my PS/2 just fine.

My terrible idea + terrible soldering
My terrible idea + terrible soldering

I had decided that since I do have a bunch of jumper cables, I could just solder them directly to the card fingers. I only have one device, so I don’t really need a ribbon cable, the BlueSCSI can emulate multiple devices, so I figured it’d be fine. Of the 50 pins in a SCSI ribbon more than half are ground, so I figured I only needed to solder up about 25 connections, just like how Apple got away with 25 pin connections. I did tone out the pins looking for the +5v power signal, along with checking the common ground, where the flip side of the SCSI card is all ground.

I had connected it up, and the machine saw the blue SCSI, but for some reason it was always reading 25Mb.

I was unable to figure out what was going on, so when I went to inspect my setup, I had seen one of the cables had disconnected. Uh-Oh.

Card edge fingers torn off
Card edge fingers torn off

As I pulled the card out of the computer, 3 more cables had popped off, revealing that the fingers were nowhere near as strong as I had thought, and the fingers had been torn off the card. Very sad. The card still ‘works’ but it’d need someone with a good eye and soldering skills to re-attach the pads, or just solder bodge wires from the test points on the card to the IDC connector.

Obviously if I’d known the fingers were so fragile, I’d have not done this. But I was impatient for the IDC connector to arrive (it took about a month), and I really thought I could get away with it. So I don’t know if it matters for anyone else, but yeah it turns out these fingers are nowhere near as strong to side to side forcers as I had thought. Also I was told “on the internet, so you know it’s true”‘ that various super glues are conductive, so test before you think about trying to do it live.

IBM SCSI Adapter FRU 15F6561 IBM MICROCHANNEL SCSI 32 bit MCA Card + Cable

And that is when this pair showed up, another SCSI card, but this time with the illusive cable. There is something weird how the universe times things.

So got this card & cable set (If it was available 3 weeks ago, obviously I would have ordered this one as it has the ribbon!).

Where the magic happens, BlueSCSI!

Not knowing much about the IBM PS/2 SCSI/A adapter, I went ahead in BlueSCSI, and setup a 380MB disk on SCSI ID 0, a 1GB disk on ID1, and a 2GB disk on ID2. That’s when I found out that the adapter initialises the bus backwards.

I had thought it was a weird thing in the setup utility, so I booted up MS-DOS and ran FDISK to reveal that it really does read the ID’s backwards.

Obviously with the BlueSCSI they are just files on a SD card, so it’s trivial to just rename them.

I had also thought it was weird that the reference disk reads the disks being 2GB just fine, so I double up with both data disks being 2GB.

And sure enough, MS-DOS only sees 1GB per bigger disk. After search for a bit, it turns out that the 1GB limitation is a known thing and newer ROMs can work around the issue. Eagle eye’d might have noticed the first adapter had ROMs from 1990, while the second card has ROMs from 1991. But the better ROMs come from a totally different card. Normally I might have been annoyed, but since my disks are virtual I can just give myself 5x1GB data disks, along with that 360MB OS disk.

ALL THE DISKS!

This is the best part of virtual peripherals, is that you can load out what would have been super expensive, and impractical for being era correct. Instead, now it’s super easy, barely an inconvenience. I can’t imagine trying to use physical disks in 2023.

One of the reasons I kept the smaller ‘C’ drive was to make for installing OSs a bit easier, as many older things hate ‘large’ disks. But being able to connect so many gives so much flexibility.

It’s a shame the MFM hard disk emulators are a bit expensive, even with my screwup it was still cheaper to go with SCSI, and the BlueSCSI basically just works, the only weird behaviour is all on the ‘tribble’ SCSI / A adapter.

Installing a Gotek floppy emulator in an IBM PS/2 model 60

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Well like everything else, once you know what to do, its pretty self explanatory and easy. But until that point it’s a lot of trail and error.

The PS/2 model of computers went away from the PC/XT/AT design for something that would be more toolless and allow for more automation in the building & assembling of these machines. That means they removed loose wiring where possible to give not only great airflow, but an overall clean aesthetic to the PS/2 build. What this also means is that the old 34pin floppy ribbon will not do.

The PS/2 version uses and edge connection and integrates the 5v/12v power rails into the interface. You can try to add an old floppy to the mix, but there is 5 pins that need to be held high through a resistor pack to get an old floppy drive working. I didn’t want to fight it that much so instead I ordered an adapter from eBay, being sold by markgm.

Yes I don’t know what is up with the shipping either.

After much trial and error I found

After a lot of trial and error I found jumpering it for S0 was what worked. While I had read that JC was also needed, it just didn’t work when I tried. S0 puts the gotek into the first floppy position, in the older PC/XT/AT’s they jumper every drive as S1, but have a twist in the cable to negate it on the primary position.

The other catch is that it absolutely required a FF.cfg file

interface = ibmpc-hdout
host=pc-dos

Even though so many other systems didn’t need it, mine sure did. And Obviously I flashed my drive to the latest version of flashfloppy (3.41 as of now.). That also meant checking the processor type, which, is simple enough to check by opening it up, and setting your camera to maximum zoom.

Gotek AT32F415 processor

Or checking the gallery of microcontrollers in the various Gotek’s. The prices have shot up dramatically over the last few years for unknown reasons, so they switched to from the ST to the AT line or similar processors.

Can’t say I blame them.

So with the drive updated, and config file loaded, along with a disk image, it finally booted up!

First boot!

And with that in place I was able to boot the reference disk, and setup the system. The inside is a bit ugly but, I wanted to get this thing fully loaded, so I picked up an 80287-10.

One interesting thing about the PS/2 line of machines is that the 286’s could run their math coprocessors in synch. The IBM-5170/AT ran it asynchronously at 2/3rds the clock value. I would have imagined they convinced someone somewhere how at big step up from a 6Mhz 80286 & 4mhz 80287 to get into a PS/2 model 50/60 with a blistering 10Mhz 80286/287.

Happily the 80287-10 I had gotten from fractal2015, worked just fine.

Wow. awesome.

I’m waiting still for some cables to hook up the bluepill to the SCSI card, and the memory card, so I can run meaningful applications like SimCity for Windows, and OS/2.

PS/2 60 playing battletech, from a gotek emulated floppy

In the meantime I can do simple stuff from floppy. I’m still trying to keep an eye out for either an ethernet card, or a Token Ring card & MAU, along with cisco cards to at least let me use NetBEUI.

But for anyone else needing a solid answer on how to get the Gotek working with an IBM PS/2 model 60, here you go!

Windows NT on IBM RS/6000 – Definitive Guide

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(This is a guest post by Antoni Sawicki aka Tenox)

Preparing for Windows NT RISC Exhibition for VCFW 2023, I wanted to have NT running on an IBM RS/6000. This was previously covered in this excellent article by Shoutmon as well in this excellent video by NCommander. However both are missing some crucial information that I had to go through and learn myself the hard way. I hope it will help someone in the future.

Windows NT PowerPC was designed to run on PReP machines, however that by itself is not very useful. Which of the RS/6000 models are REeP and which are not? This is coincidentally answered by NetBSD/prep supported system models.

Firstly there are IBM PC Power Series. Yes IBM PC but with PowerPC CPU, and not to be confused with RS/6000 which is a different IBM product. However the IBM Power Series have equivalent RS/6000 “counterpart” models. WTF IBM.

IBM PC Power Series 440 6015 == IBM RS/6000 Model 7020 40P
IBM PC Power Series 830 6050 == IBM RS/6000 Model 7248 43P
IBM PC Power Series 850 6070 == IBM RS/6000 Model 7248 43P

There are also other models mentioned by Windows NT 4.0 HCL, namely E20, E30 and F30, and PowerPC ThinkPads. To summarize here is a more definitive list of IBM RS/6000 models supported by Windows NT 4.0:

Model 7020 40P
Model 7248 43P, 100 and 133 MHz
Model 7248 43P-140 (with a big asterisk)
Model 7024 E20 and E30
Model 7025 F30
ThinkPad 820, 850
ThinkPad 860 (with a big asterisk)

If you could pick any RS/6000 machine, the 40P would probably be the most recommended. 40P can also run OS/2 PowerPC if you are in to this thing.

Unfortunately all I had on hand was 43P-140, which is PReP, but it’s not Power Series based and not supported by NT out of the box. WTF IBM. Chances are that you will run in to this as well. 43P-140 are way more popular and easier to acquire than any other hardware listed above.

The main trouble with 43P-140 is that the onboard GPU and NIC will not work with ARC and NT. Yes, you can hack in some generic S3 card. It will work in ARC/NT but not PROM and AIX. I wasn’t happy. Upon some collaboration with Shoutmon and NCcommander and my own research, I was able to find the one and only graphics card that will work in both the RS/6000 PROM as well as ARC BIOS, AIX and Windows NT. The lucky winner is:

IBM FRU 40H5838 aka GTX110P

Update: It’s been tried, tested and verified to use IBM ROM with a regular/stock S3 Trio64V+. You can download it here and program yourself.

It’s entirely possible that other adapters will work as well, however from all different cards that I tried this was the only one that worked in all combination.

As for NIC, there are way more options as it’s not used by PROM, ARC or AIX, just NT. In my case I opted for a standard Etherlink III card.

Once you have the correct hardware bits, NT installation is pretty straightforward. This is well covered elsewhere. In a nutshell you boot the ARC 1.51 floppy disk, setup partitions and install the OS. Note that the ARC BIOS will be installed in to a partition on your HDD and the floppy disk is not required beyond installation.

Installation on PowerPC ThinkPads, specifically the 860 is covered here.

86Box PS/2 model 60 emulation

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As a quick aside, on my exploring early OS/2 betas I thought I’d try to emulate the machine that I’d clearly lay the blame as to why OS/2 was fundamentally a failure, the IBM PS/2 model 60.

So IBM machines don’t use built in ROM config programs, but rather you need the reference disk. And this being a Microchannel PS/2 machine you also need the config files to support things like more than 2MB of RAM, the ESDI controller, or even an AdLib/SoundBlaster card.

updated reference disk

Adding in the RAM card, and a sound blaster adds the following cards:

However it’s worth noting that the default ESDI config/driver on the MCA confg disk won’t work on 86box. You will need an updated version.

So inside the diag disk the config will appear like this:

I’ve uploaded the reference disk on archive.org here: 86box PS/2 Model 60 Reference Disk : IBM : Free Download, Borrow, and Streaming : Internet Archive.

Unfortunately, at this moment 86Box’s PS/2 model 60 can’t run OS/2. The model 80 however has much better luck. But for anyone who want’s to play Wolf3D on an emulated 10Mhz 286, well this is your big chance.

PowerPC Solaris on the RS/6000

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The following is a guest post by PA8600/PA-RISC! Thanks for doing this incredible writeup about an ultra rare Unix!

One of the weirdest times in computing was during the mid-90s, when the major RISC
vendors all had their own plans to dominate the consumer market and eventually wipe out
Intel. This was a time that led to overpriced non-x86 systems that intended to wipe out the
PC, Windows NT being ported to non-x86 platforms, PC style hardware paired with RISC
CPUs, Apple putting the processor line from IBM servers into Macs, and Silicon Graphics
designing a game console for Nintendo. While their attempts worked wonders in the
embedded field for MIPS and the AIM alliance, quite a few of these attempts at breaking into
the mainstream were total flops.

Despite this, there were some weird products released during this period that most only assumed existed in tech magazine ads and reviews. One such product was Solaris for PowerPC. Now Solaris has existed on Intel platforms for ages and the Illumos fork has some interesting ports including a DEC Alpha port, but a forgotten official port exists for the PowerPC CPU architecture. Unlike OS/2, it’s complete and has a networking stack. It’s also perhaps one of the weirdest OSes on the PowerPC platform.

  • It’s a little-endian 32-bit PowerPC Unix and possibly the only one running in 32 bit mode. Windows NT and OS/2 (IIRC) were the other 32-bit PowerPC little-endian OSes and Linux is a 64 bit little endian OS.
  • It’s a limited access release, yet feels as polished as a released product.
  • It has a working networking stack.
  • Unlike AIX, it was designed to run on a variety of hardware with room to expand if more PPC hardware was sold. You can throw in a random 3com ISA NIC for example and it will in fact work with it.
  • It shares several things with Solaris for Intel including the installer.

I’m going to demonstrate perhaps the weirdest complete PowerPC OS on fitting hardware: the IBM RS/6000 7020 40p, also known as the Power Series 440 (6015) and by its codename “Sandalfoot”. The system is a PowerPC 601 based machine, featuring the PCI and ISA buses in an LPX style case. This is also one of the few machines that can run it. All screen captures are from a VGA2USB card as emulators cannot run anything but AIX.

What you need to run Solaris PPC

To run Solaris, the system requirements are just like that of Windows NT for PowerPC. You need a PReP machine (PowerPC Reference Platform, not to be confused with the HIV prevention pill or PrEP according to Wikipedia). Now finding a PReP machine is perhaps the hardest part of setting up Solaris for PowerPC and to understand why you need to know a bit about the history of the PowerPC platform.

One of the biggest problems with PowerPC hardware to this day has been the sheer inconsistency of how each machine boots. While Alpha machines had SRM/ARC and SPARC machines had OpenBoot, each vendor had their own way of booting a PowerPC machine despite rolling out standards.

There were essentially two different camps building PowerPC machines, IBM and Apple. IBM’s plans for universal PowerPC machines consisted of industry standard, low cost machines built around a PowerPC CPU, chipset, and lots of supporting components lifted from the PC platform along with PCI and ISA. The CHRP and PReP standards were essentially PCs with PowerPC processors in them. IBM’s plan was that you were going to replace your PC with a PowerPC machine someday. This was cemented by the fact that Windows NT was ported to the PowerPC platform, that OS/2 had an ill-fated port, and that a handful of third party Windows NT PPC machines were sold.

Apple on the other hand wanted to build Macs with PowerPC CPUs. Older Power Macs featured no PCI slots or Open Firmware, only NuBus slots carried over from classic 68k Macs. In fact much of the boot and OS code was emulated 68k code. Later on Apple would lift bits and pieces of things they enjoyed from the PowerPC standards such as Open Firmware, PCI, and even PS/2 and VGA ports on the clones. Apple’s plan was to replace the PC with the Mac, and Mac clones featured Apple style hardware on LPX motherboards. While the PCI clones featured Open Firmware, this version was designed to load the Macintosh Toolbox from ROM while “futureproofing” them by adding in the ability to boot something like Mac OS X/Rhapsody or BeOS.

Despite these similarities Macs were their own computers and were nothing like the IBM systems internally, aside from sharing the same CPU and maybe Open Firmware later on. But even Macs with Open Firmware were incapable of booting from hard disks formatted for IBM systems and vice versa. This is a common problem with installing PowerPC Linux as many installers do not check which machine they’re run on. Furthermore unlike modern day Intel Macs, PPC Macs were designed to only boot operating systems specifically written for them. They were incapable of running any OS solely written for the IBM machines.

The confusion between PPC machines has also caused a forum question to pop up, “how can I install PowerPC Windows on my Mac?” Even today the new OpenPower/PowerNV machines use a different bootloader than IBM’s hardware and completely lack Open Firmware.

Anyhow IBM built several different generations of PowerPC UNIX machines under several brand names including RS/6000, pSeries, and Power. Nearly all of them (aside from the Linux models) will run AIX, and later ones will run IBM i as well. Not just any PowerPC IBM hardware will run the OSes designed for PReP hardware however.

To run these old PReP OSes you’re looking at a very specific set of machines from the 1994-95 period, many with no characteristic diagnostic display most RS/6000 machines have. To run PowerPC Solaris much of the same applies here. You need a RS/6000 40p, or 7248 43p (not the later 140 and 150 with the display). The rare PPC Thinkpads and Personal Computer Power Series machines will run Solaris as well. It’s also compatible with the PowerStack machines from Motorola and one BetaArchive user had luck running it on a VME board. These machines are hard to find and unemulated as of writing, though the firmware files exist for the 40p at least and some efforts have been made in QEMU.

Mine features a PowerPC 601 CPU, 192mb of RAM (the max), a Weitek P9100 video card (branded as the IBM S15 IIRC), and a non-IBM 3com NIC. The 3com NIC has issues with the system as during boot if the NIC is connected to the network the system will refuse to boot fully and will either freeze or BSOD (in NT). The NIC is also not supported on AIX as well, and will eventually need to be replaced.

Curiously, not only is the IBM 40p/7020/6015 not listed in the HCL but the NIC it uses is. It’s well known that the Sandalfoot systems were used for early PReP OS development and it makes sense. Unlike the RS/6000 model 250, the 40p features PCI and ISA busses along with the same 601 CPU early PowerPC machines had. 

Installation

To install PowerPC Solaris, you first need to make a boot floppy. This isn’t uncommon with PReP operating systems. PowerPC Windows NT also requires a boot floppy for the ARC loader. The difference here is that there are two boot floppies; one for Motorola machines and one for IBM machines. Even on PowerPC this wasn’t terribly unusual, both the Moto Powerstack and Apple Network Server computers required custom AIX install media as well and Windows NT had specific HALs for each PPC machine.

On the Motorola PowerStack machines you need the same firmware used to install AIX instead of the ARC firmware for NT. On the IBM machines it’s vastly easier, you just need to make the floppy and shove it in. You then press the power switch and you’ll end up dumped to an Open Firmware prompt. As these IBM machines did not have Open Firmware, the bootloader loads Open Firmware from the floppy or hard disk every time you boot the machine. Keep in mind even the system management services are floppy loaded on these machines.

You then run into the first big hurdle to installing the OS, “disk” and “net” are mapped to very specific devices and if the SCSI IDs of these are different it will not boot. If the CD drive is not at ID 3 and the HDD is not at ID 6 the commands will not work. You will need to set an environment variable and tell it to boot from these disks manually for the first install.

Booting the OS is similar to booting it on a Sun, but the installer resembles that of the Intel version. The first thing that happens is you wait for the slow 2 speed CD drive to load the OS as the screen turns Open Firmware white. You will need to set the terminal type, and then then video and mouse input before X will load. The video options are limited to the S3 864/928, the Weitek P9000 and P9100, and Moto’s Cirrus Logic GD5434. Notice how the Power Series 440 (6015)/RS6k 7020 40p is referred to by its codename “Sandalfoot”.

Once you enter this in Solaris will boot load X it does on a Sun or Intel box, and the installer will be exactly the same. This phase is very uneventful as the slow CD drive copies files to the hard disk. I didn’t take a lot of screenshots of this part because you can get the same experience with QEMU or an old SPARCStation. You set the network info, you partition the HDD, you choose what you want, and you sit back as it installs.

Then you’ll be dropped at the Open Firmware bootloader and you’ll enter the right commands to make it boot if “boot disk” doesn’t automatically boot the OS.

The installation is not complete however. The next step is to swap CDs and install the GUI. A default install will drop you at a command line, with the second disk you can install OpenWindows and CDE and get a full working desktop. Login, switch CDs, change to the correct directory, and run the installer.

Once this is done, simply type in reboot and once you login you’ll be at a desktop that looks exactly like a Solaris 2.5.1 install on any other platform with one difference. There is literally zero third party software, and for years there was literally zero way of making software for it. You’re stuck with a stock OS and whatever utilities Solaris 2.5.1 came with. You’ll want to use OpenWindows as well, CDE is vastly slower on the 601 CPU (but not as slow as AIX 4.3 for example). The platform directory also tells you what IBM machines it can run on, and all the RS/6000s are titled PPS. The 6015 is the 40p, the 6040 and 6042 are the ThinkPad models 830 and 850, the 6050/70 are the Personal Computer Power Series variants of the 7248 43p, and the PowerStacks are pretty self-explanatory.

The Compiler Problem (and solutions)

For the longest time Solaris for PowerPC was neglected among those who happened to own a PReP machine for one reason: it lacked a compiler. A compiler is perhaps the most important part of any operating system as it allows one to write code for it. As was the case with UNIX operating systems from the time, the compiler was sold separately. With any UNIX that was widely distributed this wasn’t too much of an issue, as GCC or other third party compilers existed for the platform. Furthermore most compilers for these commercial UNIX operating systems ended up dumped online.

Solaris for PowerPC lacked both of these for ages due to the obscurity and rarity of the port. But in 2018 Tenox dug up the official compiler, yet this remained unnoticed for a while. This led to someone else experimenting with cross compilation on Solaris, and managing to compile PowerPC Solaris software. They then released a port of GCC for Solaris 2.5.1 for PowerPC while posting instructions on how to compile it.

To use GCC for Solaris, you need to unzip the compiler, add it to the path, and then symlink a few files that GCC ends up looking for. This is discussed in the BetaArchive thread about this, but I’ll quote it here.

$ ls -l /opt/ppc-gcc/lib/gcc-lib/powerpcle-sun-solaris2/2.95/
total 13224
-rwxr-xr-x   1 bin      bin      5157747 Feb 16 10:30 cc1
-rwxr-xr-x   1 bin      bin       404074 Feb 16 10:30 collect2
-rwxr-xr-x   1 bin      bin       453525 Feb 16 10:30 cpp
-rw-r--r--   1 bin      bin         1932 Feb 16 10:30 ecrti.o
-rw-r--r--   1 bin      bin         1749 Feb 16 10:30 ecrtn.o
drwxr-xr-x   3 bin      bin         1024 Feb 16 10:29 include
-rw-r--r--   1 bin      bin       673012 Feb 16 10:30 libgcc.a
drwxr-xr-x   2 bin      bin          512 Feb 16 10:30 nof
-rw-r--r--   1 bin      bin         4212 Feb 16 10:30 scrt0.o
-rw-r--r--   1 bin      bin         1360 Feb 16 10:30 scrti.o
-rw-r--r--   1 bin      bin         1104 Feb 16 10:30 scrtn.o
-rw-r--r--   1 bin      bin         7868 Feb 16 10:30 specs
lrwxrwxrwx   1 root     other         24 Feb 22 21:35 values-Xa.o -> /usr/ccs/lib/values-Xa.o
lrwxrwxrwx   1 root     other         24 Feb 22 21:36 values-Xc.o -> /usr/ccs/lib/values-Xc.o
lrwxrwxrwx   1 root     other         24 Feb 22 21:36 values-Xs.o -> /usr/ccs/lib/values-Xs.o
lrwxrwxrwx   1 root     other         24 Feb 22 21:36 values-Xt.o -> /usr/ccs/lib/values-Xt.o
lrwxrwxrwx   1 root     other         26 Feb 22 21:37 values-xpg4.o -> /usr/ccs/lib/values-xpg4.o
$

Once you do this, you can now compile C code at least with GCC. This means that Solaris for the PowerPC platform now is a usable operating system, aside from the fact it has no precompiled software whatsoever. Even Windows NT for PowerPC has more software for it. Software can now be compiled using GCC or the original compiler, and cross compiled with GCC on a non-PPC box. Using the cross compiler lets you compile more basics for compiling PPC Solaris code as well such as make. In this screenshot you can also see me compiling a basic “endian test” code example to demonstrate the little endianness of the PowerPC port.

The only problem is that there’s going to be little interest until someone makes a PReP machine emulator. PReP hardware is very hard to come by on the used market these days and while in the early 2000s it might have been easy to find something like a specific RS6k, but judging by the eBay listings there were a lot more MCA, CHRP, and even later PReP models (like the 43p-140) than there are early PReP machines in circulation. QEMU can emulate the 40p somewhat, but right now its 40p emulation is less like an actual 40p and more like something to please AIX. It definitely has the novelty of being a “little-endian PowerPC Unix” however.

Installing AIX on Qemu!

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YES it’s real!

I’m using the Linux subystem on Windows, as it’s easier to build this Qemu tree from source. I’m using Debian, but these steps will work on other systems that use Debian as a base.

First thing first, you need to get your system with the needed pre-requisites to compile:

apt-get update;apt-get upgrade apt-get install build-essential pkg-config libz-dev libglib2.0-dev libpixman-1-dev libfdt-dev

Great with those in place, now clone Artyom Tarasenko’s source repository

git clone --branch 40p-20190406-aix-boots --single-branch https://github.com/artyom-tarasenko/qemu.git

*NOTE from the future (2022) you may want to jump here: to check out building on newer systems. Also don’t forget about networking!

Since the frame buffer apparently isn’t quite working just yet, I configure for something more like a text mode build.

././configure --target-list=ppc-softmmu --disable-sdl --disable-vnc --disable-gtk --disable-gnutls --disable-nettle --disable-gcrypt --disable-spice --disable-numa --disable-libxml2 --disable-werror

Now for me, GCC 7 didn’t build the source cleanly. I had to make a change to the file config-host.mak and remove all references to -Werror. Also I removed the sound hooks, as we won’t need them. remove the following lines:

CONFIG_AUDIO_DRIVERS=oss CONFIG_AUDIO_OSS=m

Now you can build Qemu. it’ll happily build in parallel so feel free to build using the -j parameter with how many cores you have. I have 32, so I use

make -j32

Okay, all being well you now have a Qemu. Now following the steps from
Artyom Tarasenko’s blog post, we can get started on the install!

First we create a 8GB disk

qemu-img create -f qcow2 aix-hdd.qcow2 8G

Next we need the custom BIOS with serial as the console.

wget https://github.com/artyom-tarasenko/openfirmware/releases/download/40p-20190413/q40pofw-serial.rom

You’ll need some AIX. I tried a 3.2.5 CD-ROM and it didn’t pick up, but AIX 4.3.3 did.

Now with all those bits in place, it’s time to run Qemu.

./ppc-softmmu/qemu-system-ppc -M 40p -bios q40pofw-serial.rom -serial telnet::4441,server -hda aix-hdd.qcow2 -vga none -nographic -net none -cdrom Volume_1.iso

Now telnet to your localhost on port 4441 and you will see the console doing it’s BIOS initialize and eventually drop to the OK prompt.

One trick I’ve found is that from the Open Firmware prompt you can find out what partitions are recognized from the firmware. If it see’s partitions then there is some hope that the image you have is valid enough to boot. In the last few days I’ve found quite a few AIX images, which are lacking the partition table, and unable to boot.

.partitions cdrom

simply type in boot cdrom:2 to kick off the installer. It may take a minute or so for the installer to kick off.

If all goes well, you’ll see the BIOS reload itself, then after a minute you’ll be prompted to press 1 to select the console

It doesn’t echo, don’t panic!

Next select your language. I’m doing English.

Next it’ll ask about installation type. Default ought to be fine.

Because this will destroy the contents of the disk (which doesn’t matter as it’s blank) it’ll prompt for confirmation.

After this it’ll begin the installation. Depending on how fast your disk & CPU is this will take a while.


For me, the installation took about 11 minutes. This is using my Xeon E5-2667 v2. It took 17 minutes on my 2006 Mac Pro, with X5365’s it .

After it’s done, right around the 96% time it’ll reboot back to the BIOS

Once you are back at the OK prompt, you can now boot disk:

it’ll look like it’s hung for a minute, then it’ll start booting from disk!

Once the OS is booted up, you select the terminal type. I’m using putty but I’ll select the vt100. Of note the function keys are selected by hitting escape and then the number key. So F3 is ESC 3.

I’m just going to finish the install, as we can always run smitty to mess with the system more, but right now I’m just interested in a base install of the BOS (Base Operating System, and IBM ISM).

A few moments later, you’ll get dumped to the login prompt.

By default there is no password, so just login as root, and there you go, your very own virtual AIX 4.3 system.

# uname -a AIX localhost 3 4 000000004C00

So there you go! All thanks to Artyom’s hard work!

Citrix Multiuser 2.0

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Back before selling auto insurance

Citrix Multuser 2.0

Nothing like a little vintage advertising to try to re-capture the feel.  But don’t let the colorful lizard fool you, this certainly was a dark time for Citrix.  Firs they had tooled a product around the future of the PC market, OS/2 to only have Microsoft pull out of active development just as they were launching Multiuser 1.0.  And to be fair it wasn’t just Citrix, the whole industry including Microsoft was in turmoil as people were pulling away from IBM and selecting Windows on MS-DOS of all things!

Citrix, like a lot of vars were caught in this lurch between OS/2 and the forthcoming NT OS/2 3.0, which of course ended up becoming Windows NT.  During this time even Microsoft had to keep selling it’s SQL server on OS/2, along with it’s LanManager file & print server.  Although they had a solution for the end user in the form of Windows they didn’t have any server platform.  That left Citrix chasing the tail end of the application wave again as although they could now finally use OS/2 2.0, with it’s 32bit/16bit hybrid kernel, there remote user solution was still terminal based.

IBM OS/2 ad

As IBM & Microsoft had split up the direction of the OS/2 project, IBM was running with version 2 as a platform for running DOS & Windows applications.  Which ultimately lead to the major problem that OS/2 ran Windows apps better than native Windows thanks to it’s ability to run isolated Windows VM’s using paravirutalized graphic drivers.  It wasn’t until Windows NT 3.5 could Microsoft meet this feat with it’s new platform.  Suddenly Citrix had access to tonnes of MS-DOS based applications, much to my surprise there is even a DPMI driver on the disks I have, meaning that Windows 3.0 standard mode can run, along with DooM!  But for Citrix this would be another one of those ‘not good enough’ moments where PC Servers were just high end workstations that could easily be maxed by one user, commodity multiprocessor machines were years off, and of course everyone was jumping to Windows 3.0.

But this did at least you run MS-DOS applications remotely, over dialup.

Citrix multiuser 2.0 boot

Installing Citrix Multiuser 2.00 starts looking very much like one of the 1.x versions of OS/2 with a far more busier screen featuring the Citrix tree.  However from this point onward it feels a LOT more like IBM OS/2 2.00.  Citrix interestingly enough has two disk 1’s, one that features newer LADDR drivers, and another with the older 1.x drivers.  Although under bochs, the older driver disk crashes out.  The entire OS fits on 8 high density 5 1/4″ diskettes.  As teased before this post, I saw this on eBay, ordered it immediately to only discover that I don’t have the needed drive, and had to order one from pc-rath_de, and I wanted to give a shout out, as he made sure that I had the proper floppy ribbon cable, so I could go ahead with this fun project.

Although I had been expecting this to be inline with the never released Microsoft OS/2 2.00, it clearly has a lot of IBM vestige, even though the OS/2 source code license agreement was between Citrix and Microsoft.

Indeed, even checking the OS level:

IBM OS/2 Base Operating System
Standard Edition 2.00     Component ID 560109001
Current CSD level: XR00000
Prior   CSD level: XR00000

Compare this to the OS/2 2.00 GA:

IBM OS/2 Base Operating System
Version 2.00 Component ID 562107701
Type 0
Current CSD level: XR02000
Prior CSD level: XR00000

So clearly this is not in sync with the General availability of OS/2.  What this is closer to sync with is the OS/2 LA – Limited Availability release.

IBM OS/2 Base Operating System
Standard Edition 2.00 Component ID 560109001
Current CSD level: XR00000
Prior CSD level: XR00000

Well isn’t that interesting?

Having had the misfortune of crashing all three we can look at the internal revisions:

Citrix Internal revision 2.053 6.177H base

LA Internal revision 6.167 91-10-08

GA Internal revision 6.307 92-03-01

So this make the BOS (Base Operating System in IBM speak) newer than the OS/2 LA (Limited Availability) kernel, however quite a few revisions behind the GA (General Availability).  This of course means that Citrix Multiuser 2.0 is basically incompatible with any 32bit OS/2 software.  I was unable to run anything EMX based, nor could I run the vast majority of the 32bit TCP/IP stack for OS/2 2.00.  The best I could do was have it load the drivers, to where I could setup and ping the loopback, but the route command crashes the system, and any of the commands simply refuse to run.  Not being able to run 32bit OS/2 applications greatly reduces the usability of the system, and falls further to the OS/2 trap that it really just excels at running MS-DOS apps.

It was a bit of a surprise to find out that even though Citrix had their source license through Microsoft, the 2.0 components turned out to be the upstream components from IBM.  Just as the included Qbasic is the IBM version, along with the other components.  The terminal support is naturally more robust than version 1, although I think the larger problem I had trying to run OS/2 programs it that many terminals are hard coded for 24 lines, and I don’t think you can change that in Citrix.  And it does mention that if you do try to run on a 24 line terminal that DOS won’t run.

Much like 1.0, all the administration is done via text tools.  It feels weird at first as even on the console there doesn’t seem to be any mouse integration, although the installer does ask if you do have a mouse on the system.

And like 1.0 there is no Presentation Manager, so no graphics on the console.  HOWEVER you can run MS-DOS graphical stuff on the console. Although today I have no real need for it, but I went ahead and setup the included Windows support.

Windows for OS/2

What is interesting is that you are expected to supply your own retail version of Windows 3.00, and Citrix has some updated drivers, along with OS2K286.EXE, and updated program manager, control panel, and print manager.  While IBM included a full copy of Windows 3.00 at this point, this feels like the beginning of OS/2 for Windows – AKA the Borg.

Going Multiuser

First I just setup a COM port on Bochs to Listen on port 8880.  Unfortunately this isn’t resilient, as Bochs will wait for a connect before actually starting, and if you drop off, it won’t let you connect back in.

com1: enabled=1, mode=socket-server, dev=localhost:8880

And then it’s a matter of running CFGTERM, and adding in the Async module.

Citrix add in Async

With the module added you then just have to assign a port.

ICA profile

I didnt’ do anything special other than telling Citrix that there is no modem, it’s a direct connect, and to use the ICA terminal profile.

Using the Citrix MultiLink program, and DOSBox I was able to add an ICA terminal.  On DOSBox I had to specify a modem with an IRQ in the config like this:

serial2=modem irq3 listenport:5001

CML modem settings

In the modem settings I had to set this to Forced connect, otherwise it’ll never see the server.

CML dialup profile

And here is how I ‘called’ the Bochs VM.  And then after ‘dialing’ in Bochs will start up the Citrix VM, and then you’ll get the simple Login prompt.  Login and you’ll get pselect.

Logging in to Pselect

Pselect the the text based UI tool to get around your OS/2 sessions.  It’s a little cumbersome at first, but once you get used to it, it’s just like OS/2 1.0 … Or Multiuser 1.0 for that matter, nothing really changed, except you can start MS-DOS Sessions now.

MS-DOS over the serial port

And yes, you can run Qbasic.  But you can’t do anything graphical. Not even DooM.  Although after loading the VDPMI device driver, DooM v1.1 will run, but then it’ll give you this fun error:

No graphics over the serial line

And that is where I’m going to have to leave this adventure for now.  If you are so inclined, you can pick it up on archive.org.