Bringing Up An Old Motherboard Is A Delicate Process

November 12, 2022 by Dan Maloney 12 Comments

If you were around for the early days of the personal computer revolution, you’ll no doubt recall the excitement every time IBM announced a new version of its beige boxes. For a lot of us, the excitement was purely vicarious, for despite the “personal” moniker, mere mortals could rarely afford a branded IBM machine. But it was still cool to keep track of the latest releases, and dream of the days when cheap clones would make it possible to play.

[Anders Nielsen]’s recent find of an original IBM Model 5160 motherboard sort of echoes that long-ago excitement, but in a different way. This board, from a PC XT built in 1984, was in unknown condition upon arrival, so [Anders] set about a careful process to try to bring the board back to life. A quick visual inspection leaves one with a sense of both how much things have changed, and how much they’ve stayed the same. Aside from the big 40-pin DIP 8088 CPU and the BIOS ROMs, the board is almost completely populated with discrete logic chips, but at the same time, the basic footprint of a motherboard has changed very little.

The bring-up process in the video below includes checks of all the power rails for shorts, which ended up being a good call — drat those tantalums. After fixing that issue, [Anders] had a bit of trouble getting the board to POST, and eventually resorted to dumping the BIOS ROMs and inspecting the contents. One of the chips had picked up a case of the scramblies at some point, which was easy enough to fix thanks to images of the 5160 ROMs available online. We thought the trick of using a 64k ROM and just writing the BIOS image twice was pretty clever.

In the end, the board came up, although without video or keyboard — that’s for another day. Can’t find your own PC XT motherboard to play with? Then maybe you can just build one.

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IBM Made A MIPS Laptop. Will It Make You WinCE?

September 29, 2022 by Jenny List 26 Comments

We’re used to our laptop computers here in 2022 being ultra-portable, super-powerful, and with impressively long battery lives. It’s easy to forget then that there was a time when from those three features the laptop user could usually expect only one of them in their device. Powerful laptops were the size of paving slabs and had battery lives measured in minutes, while anything small usually had disappointing performance or yet again a minuscule power budget.

In the late 1990s manufacturers saw a way out of this in Microsoft’s Windows CE, which would run on modest hardware without drinking power. Several devices made it to market, among them one from IBM which [OldVCR] has taken a look at. It makes for an interesting trip down one of those dead-end side roads in computing history.

In the box bought through an online auction is a tiny laptop that screams IBM, we’d identify it as a ThinkPad immediately if it wasn’t for that brand being absent. This is an IBM WorkPad, a baby sibling of the ThinkPad line intended as a companion device. This one has a reduced spec screen and an NEC MIPS processor, with Windows CE on a ROM SODIMM accessible through a cover on the underside. For us in 2022 MIPS processors based on the open-sourced MIPS ISA are found in low-end webcams and routers, but back then it was a real contender. The article goes into some detail on the various families of chips from that time, which is worth a read in itself.

We remember these laptops, and while the IBM one was unaffordable there was a COMPAQ competitor which did seem tempting for on-the-road work. They failed to make an impact due to being marketed as a high-end executive’s toy rather than a mass-market computer, and they were seen off as “real” laptops became more affordable. A second-hand HP Omnibook 800 did the ultra-portable job on this bench instead.

The industry had various attempts at cracking this market, most notably with the netbooks which appeared a few years after the WorkPad was produced. It was left to Google to reinvent the ultra-portable non-Intel laptop as an internet appliance with their Chromebooks before they would become a mass-market device, but the WorkPad remains a tantalizing glimpse of what might have been.

Windows CE occasionally makes an appearance here, and yes, it runs DOOM.

The Hunt For A Rare Version Of IBM’s OS/2

September 12, 2022 by Jenny List 40 Comments

Slovenian OS/2 Warp 4 was a popular OS choice in that European country back in the day, but could the Slovenian Computer Museum lay their hands on a copy? In that question lies a bit of detective work and some luck.

There’s an old gag, about how this is finally the year of the Linux desktop. But oddly back in the ’90s it almost seemed possible, because alongside Microsoft Windows there were a host of other players that just might have become challengers. Foremost among them was IBM’s OS/2, a desktop PC operating system that could very much give Windows a run for its money. It could even run 16-bit Windows applications thanks to the code-sharing deal between the two companies dating back to the DOS days. Big Blue were so anxious to take their OS into new markets that they localized it into languages which Microsoft hadn’t touched, of which Slovenian was one.

But a couple of decades later, could a copy of this rare operating system version be found? While it may still lurk on a dusty shelf in an IT office somewhere it’s proved elusive, and online sources have dried up. The quest for it makes interesting reading for anyone with an interest in that period of retrocomputing, and finally ended up at the Slovenian company which had performed the localisation. This resulted in a copy of the OS, but not of the media, box, or paperwork. It yielded the fascinating discovery that IBM had localized the Windows 3.1-derived components as well as their own code, something that Microsoft had never done.

So do you have a boxed Slovenian OS/2 Warp 4 on a dusty shelf? Someone at the Slovenian Computer History Museum might like to see it. Meanwhile it’s a surprise to find that OS/2 is still supported.

IBM’s Early PC Attracts Time Travelers

August 23, 2022 by Al Williams 51 Comments

It wasn’t long ago I was nostalgic about an old computer I saw back in the 1980s from HP. It was sort of an early attempt at a PC, although price-wise it was only in reach for professionals. HP wasn’t the only one to try such a thing, and one of the more famous attempts was the company that arguably did get the PC world rolling: IBM. Sure, there were other companies that made PCs before the IBM PC, but that was the computer that cemented the idea of a computer on an office desk or at your home more than any computer before it. Even now, our giant supercomputer desktop machines boot as though they were a vintage 1981 PC for a few minutes on each startup. But the PC wasn’t the first personal machine from IBM and, in fact, the IBM 5100 was not only personal, but it was also portable. Well, portable by 1970s standards that also had very heavy video cameras and luggable computers like the Osborne 1.

The IBM 5100 had a brief three-year life from 1975 to 1978. A blistering 1.9 MHz 16-bit CPU drove a 5-inch CRT monitor and you could have between 16K and 64K of RAM along with a fair amount of ROM. In fact, the ROMs were the key feature and a giant switch on the front let you pick between an APL ROM and a BASIC ROM (assuming you had bought both).

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Your Own IBM Mainframe (or Vax, Or Cray…) The Easy Way

June 19, 2022 by Al Williams 34 Comments

If you want the classic experience of working with an IBM mainframe or another classic computer like a DEC VAX, you have a few choices. You could spend a lot of money trying to find one, transport it, and refurbish it. But, of course, most of us will settle for an emulator. While there are great emulators out there, most of the time you aren’t interested in running just the bare machine — you want the operating systems, the compilers, and the other software that made these machines so interesting. Running your three lines of machine code isn’t as much fun as playing hunt the wumpus or compiling some Fortran IV code. Unfortunately, finding copies of all this old software can be daunting. But thanks to the efforts of [Rattydave], you can do it with no problems at all. The secret? Pre-built docker images that have everything you need in one place.

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Custom 40% Model F Keyboard Is 100% Awesome

June 16, 2022 by Kristina Panos 41 Comments

Look closely at this beauty. No, that’s not a chopped IBM Model M or anything — it’s a custom 40% capacitive buckling spring keyboard with an ortholinear layout made by [durken]. Makes it easy to imagine an alternate reality where IBM still exists as IBM and has strong keyboard game, or one where Unicomp are making dreams come true for those who don’t need anywhere near 101 or 104 keys.

Buckling what now? This lovely board uses capacitive buckling spring switches from an old IBM Model F. Basically, every time you press a key, a little spring is bent over (or buckled) in the name of connectivity. In the capacitive version, the spring pushes a hammer onto a pair of plates, causing a change in capacitance that gets recognized as a key press. In this case, those key presses are read by a TH-XWhatsit controller.

Using a Model F XT’s PCB as a guide, [durken] made a field of capacitive pads on one PCB, and made a second, ground plane PCB to avoid interference. In a true homage to these keyboards, [durken] decided to curve the PCB slightly, which naturally complicated almost everything, especially the barrel plate.

The solution was to make a separate barrel plate that slides into the case and gets screwed to the top via mounting bracket. For an extra bit of fun, [durken] mounted an SKCL lock switch under the IBM logo which enables solenoid mode. Be sure to check that out in the (updated!) video after the break.

One of the best things about a buckling spring keyboard is that each key sounds slightly different. Not so in solenoid mode, unless you were to use multiple solenoids.

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Have You Heard Of MCGA?

June 2, 2022 by Jenny List 21 Comments

In the world of PC graphics, the early standards followed the various video cards of the day. There was MDA, familiar through the original text-based DOS prompt, CGA, then EGA, and the non-IBM Hercules along the way. Finally in 1987 IBM produced the VGA, or Video Graphics Array standard for their PS/2 line of computers, which became the bedrock on which all subsequent PC graphics cards, even those with digital outputs, have been built. It’s interesting then to read an account from [Dave Farquhar] of the other now-forgotten video standard that made its debut with the PS/2, MCGA, or Multicolor Graphics Array. This was intended as an entry-level graphics system to compete with the more multimedia-oriented home computers of the day such as the Commodore Amiga and Atari ST.

Offering 320×200 graphics at 256 colors but only two colors at 640×480 it’s difficult to see how it could have been a viable competitor to the Amiga’s 4096-color HAM mode, but it did offer the ability to drive an RGB monitor through its VGA-like socket. The story goes that IBM intended it to provide an upgrade incentive for PS/2 customers to buy a more powerful model with VGA, but in the event a host of third-party VGA-compatible cards emerged and allowed more traditional ISA computers from third parties to retain a competitive edge and eventually sideline the PS/2 line entirely.

We called time on VGA back in 2016, and it’s fair to say that it’s disappeared from PC hardware since then even if much of its technologies still lurk within. It’s pleasing to see though that it remains a stalwart of hacked-together display interfaces, with efforts such as this 7400-based VGA card continuing to impress us.