Windows 95, With Just A Floppy Drive

October 26, 2025 by Jenny List 45 Comments

It’s something of a shock to be reminded that Microsoft’s Windows 95 is now 30 years old — but the PC operating system that brought 32-bit computing to the masses and left behind a graphical interface legacy which persists to this day, is now old enough that many in the community have never actually seen it. The original requirements were a 386 or better, 4 megabytes of memory, and a hard drive. [Robert’s Retro] is exploding one of those requirements, creating a full Windows 95 install using only a floppy drive.

As you might imagine, even if you had one of the super-rare 2.88 megabyte drives, such a feat would require a few tricks. In this case the biggest trick is the FlashPath, a curious 1990s peripheral that allows a SmartMedia card to be used in a floppy drive. With a special DOS driver it allows what is in effect a 32 megabyte floppy disk, but even that’s not enough for ’95. In come a couple of further tricks, installing Windows 95 to a compressed DriveSpace volume which is copied to the FlashPath, and copying the Drivespace volume to a RAM drive and mounting it, on boot. It needs a conventional floppy to boot before swapping to the FlashPath and it seems the copying process is extremely slow, but we’d expect Windows 95 from RAM to be very quick indeed.

There have been other minimalist Windows 95s over the years, but what makes this one unusual is that it’s a full install. Five years ago at the OS’s quarter century we took a look at it with 2020 eyes, and tried gauge its effect on modern desktops.

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Relay Computer Knows The Sequence

October 25, 2025 by Al Williams 11 Comments

When we first saw [DiPDoT’s] homebrew computer, we thought it was an Altair 8800. But, no. While it has a very familiar front panel, the working parts are all based on relays. While it isn’t finished, the machine can already do some simple calculations as you can see in the video below.

Turns out, the Altair front panel isn’t a coincidence. He wants to put the device in an Altair-style case. This limits him to two backplane cards, but he’s running out of space, so part of what he does in the video is redesign the backplanes.

We need to watch some more of these videos to figure out how he’s making his logic gates. A common approach is to wire AND gates as series relays and OR gates as parallel relays. However, there are some advantages to using relays as two-to-one multiplexers, which can create any logic gate you want.

If you just want to see the computer run, you can watch it generate a Fibonacci sequence around the 14:30 mark. Glorious sound from a beautiful bunch of relays. Not exactly a speed demon, mind you, but not half bad for a bunch of electromechanical relays.

There was a time when computers like this were state-of-the-art. In a way, we miss those days. But then again, in some ways, we don’t.

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The Isetta TTL Computer Makes Some Noise

October 24, 2025 by Jenny List 5 Comments

Our Hackaday colleague [Bil Herd] is known for being the mind behind the Commodore 128, a machine which famously had both a 6502 and a Z80 processor on board. The idea of a machine which could do the job of both those processors in hardware while containing neither would have blown the mind of any 1980s computer enthusiast, yet that’s exactly what [Roelh]’s Isetta TTL computer does. It’s an extremely clever design whose targeted microcode allows the processor-swap trick, and since he’s brought it from prototype to production and has it running SymbOS since we last saw it, it’s time we gave it another look.

A diagram showing chip placement on the Isetta PCB. — All the functions on what is a surprisingly compact board.

The video below the break shows the machine in action, with the Windows 95-like SymbOS GUI running a series of sound tests in the emulated AY-3-8910 sound generator, as well as a Lemmings-like game. It also runs Sinclair ZX Spectrum software, giving it access to a huge library.

We were lucky enough to see some of this in person when we encountered it for a second time on our travels during the summer — and it’s just as impressive in the real as it looks in the video. The feeling really hits you of how this would have blown away anything on the 8-bit market in 1985, made more impressive by the silicon in use being not too far from what was available at the time.

We’re told you can now buy one for yourself as a kit, and we’re looking forward to seeing it generate an ecosystem. We’re particularly curious as to whether that retargetable microcode could allow it to support other archetctures of the day.

Our original coverage can be read here, and we’ve also touched upon SymbOS.

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The PDP-1 Can Sound Hauntingly Beautiful

October 21, 2025 by Lewin Day 13 Comments

The chiptune music scene is largely rooted in the sounds of the original Nintendo Game Boy and the Commodore 64, while still welcoming a wide range of other hardware under its general umbrella. Still, few chip musicians show up to a gig hauling a PDP-1. That’s perhaps a shame, given that the 1950s era machine can produce beautiful music—as demonstrated by [Peter Samson] and [Joe Lynch].

The video demonstration was recorded at the Computer History Museum in Mountain View, California. [Peter Samson] is operating the PDP-1, which is running the Harmony Compiler—which allows the machine to play four individual voices. This is achieved by taking advantage of the PDP-1’s program flags, which are visible as six light bulbs on the control panel. Instructions can be used to turn these bulbs on and off. The Harmony Compiler works by switching the bulbs on and off fast enough to create audible square waves when the light bulb outputs are wired to a simple audio amplifier.

Using Harmony Compiler, [Joe] and [Peter] worked together to transcribe the song Olson by Boards of Canada to play on the PDP-1. The song is encoded on paper tape, and fed into the machine—which dutifully plays back the hauntingly beautiful melody.

If you’re interested in the code that achieved this, it’s blessedly available via Github. If you love stories about old computers playing music, we’ve got those too. Video after the break.

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British Train Departures As They Should Be Viewed

October 21, 2025 by Jenny List 33 Comments

The first generation of real-time train information screens for British railways came in the form of suspended color CRTs in familiar rounded fiberglass housings. They were a ubiquitous sight across the network for years, until of course suddenly, they weren’t. Can they be brought back? [Heliomass] has come about as close as it’s possible to be, with a modern emulation that runs from live data feeds.

The screens were recognizably using the same graphics standards as Teletext, and thus it was no surprise back in the day to see from time to time an Acorn boot screen in a railway station.

We remember some debate at the time as to whether they were running Archimedes of BBC Micro hardware behind the scenes, though it seems likely it might have been the industrial BBC Micro derivative.

The modern recreation uses an emulated BBC Micro for the signage, with a serial connection to a server component running in Python on more modern hardware. This handles grabbing the data and sending it to the Beeb for display. The result is an unexpected bit of nostalgia for anyone who spent the 1980s or ’90s in south east England.

Putting A Teensy To Task As A Transputer Link

October 20, 2025 by Dave Rowntree 8 Comments

One downside of working with the old Inmos Transputer devices is the rarity and cost of the original silicon. Obviously, you can’t sidestep the acquisition of the processor—unless you emulate—but what about replacing the IMS C011/C012 link chip? You need this (expensive) part to interface the transputer to the programming host, but as [Erturk Kocalar] discovered, it’s perfectly possible to coax a Teensy to do that job for you just as well.

The unusual two-bit start sequence differentiates a data packet from an ACK. It’s simple to emulate if you use the LSB of a 9-bit word as a dummy start bit!

Transputers work by utilizing an array of bit serial interfaces to connect a network of devices, allowing for cooperative computation on tasks too large to fit on a single device. This protocol is, at its link level, a simple asynchronous bit serial affair, with 11-bit data messages, and a raw two-bit frame for the acknowledge. The C011 device at its heart is just a specialized UART—it takes 8-bit parallel data from the host, dealing with handshaking, and pushes it out to the first transputer in the chain at 5, 10 or 20 Mbps, but inverted and with two start bits and a single stop bit. In parallel, it performs the same task in the reverse direction.

[Erturk] realized that the Teensy UART has an inverted mode and, crucially, a 9-bit data mode. This allows the second start bit to be generated as bit 0 of the word, with the remaining eight bits forming the payload. Simple stuff. Additionally, the Teensy UART is capable of the maximum transputer bitrate of 20 Mbps, without breaking a sweat.

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Left: old and busted. Right: New hotness.

Game Of Theseus Gets Graphics Upgrade, Force Feedback 30 Years On

October 19, 2025 by Tyler August 9 Comments

Indycar Racing 2 was a good game, back in 1995; in some ways, it was the Crysis of the Clinton years, in that most mortals could not run it to its full potential when it was new. Still, that potential was surely fairly limited, as we’re talking about a DOS game from 30 years ago. Sure, it was limited– but limits are meant to be broken, and games are made to be modded. [TedMeat] has made a video showing the updates. (Embedded below.)

It turns out there was a 3D-accelerated version sold with the short-lived Rendition graphics cards. That version is what let the community upscale everything to the absurd resolutions our modern monitors are capable of. Goodbye SVGA, hello HD. Specifically, [sharangad] has created a wrapper to translate the Rendition API to modern hardware. It doesn’t sound like higher-res textures have been modded in, in which case this looks spectacular for graphics designed in 1995. It’s not the latest Forza, but for what it is, it impresses.

The second hack [TedMeat] discusses is a mod by [GPLaps] that pulls physics values from game memory to throw to a modern force-feedback wheel, and it shows just how good the physics was in 1995. You really can feel what’s going on– stopping a skid before it starts, for example. That’s normal these days, but for the kids playing with a keyboard in 1995, it would have been totally mind-blowing.

As tipster [Keith Olson] put it: “What can I say? Fans gonna fan!” — and we’re just as grateful for that fact as we are for the tipoff. If you’re in a fandom that’s hacked its way to keep old favourites alive, we’d love to hear about it: submit a tip.

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