Can Claude Write Z80 Assembly Code?

April 19, 2026 by Tyler August 28 Comments

Betteridge’s law applies, but with help and guidance by a human who knows his stuff, [Ready Z80] was able to get a functioning game of Wordle out of the French-named LLM, which is more than we expected. It’s not like the folks at Anthropic spent much time making sure 40-year-old opcodes were well represented in their training data, after all.

For hardware, [Ready Z80] is working with the TEC-1G single-board-computer, which is a retrocomputer inspired by the TEC-1 whose design was published by Australian hobbyist magazine “Talking Electronics” back in the 1980s. Claude actually seemed to know what that was, and that it only had a hex keypad — though when [Ready Z80] was quick to correct it and let the LLM know he’s using a QWERTY keyboard add-on, Claude declared it was confident in its ability to write the code.

As usual for a LLM, Claude was overconfident and tossed out some nonexistent instructions. Though admittedly, it didn’t persist in that after being corrected. It’s notable that [Ready Z80] doesn’t prompt it with “Give me an implementation of Wordle in Z80 assembly for the TEC-1G” but goes through step-by-step, explaining exactly what he wants each section of the code to do. As [Dan Maloney] reported three years ago, it’s a bit like working with a summer intern.

In the end, they get a working game, but that was never in question. [Ready Z80] reveals over the course of the video he has the chops to have written it himself. Did using Claude make that go faster? Based on studies we’ve seen, it probably felt like it, even if it may have actually slowed him down.

Continue reading “Can Claude Write Z80 Assembly Code?” →

What Can You Run On A 1960s Univac? Anything You’re Willing To Wait For!

April 18, 2026 by Tyler August 14 Comments

There are two UNIVAC 1219B computers that have survived since the 1960s and one of them is even operational. [Nathan Farlow] wanted to run a Minecraft server on it, so he did. After a lot of work, of course, which is described in a detailed blog post, and, a YouTube video by [TheScienceElf] we’ve embedded below.

The UNIVAC is a seriously weird architecture by modern standards: it’s got eighteen-bit words — yeah, not even a power of two — and one’s compliment arithmatic with a weird signed zero thing going on. There’s one 36-bit and one 18-bit register, and only 40,960 words of memory. Eighteen-bit words. Yeah, it was the 1960s and they were making it up as they went along.

[Nathan] wasn’t, entirely, as this weird system is both well-documented and already had an emulator — in BASIC, of all things. [TheScienceElf] used the docs and the existing emulator to recreate his own in Rust so he could test their somewhat crazy plan without wasting cycles on real hardware. The plan? Well, there are really only two options if you want to build modern software for a niche architecture: one is to add niche support to something like GCC, and the other is to write a RISC V emulator and compile to that. We’ve seen that second one before, and that’s the route [Nathan] took.

Of course, [Nathan] is a machine learning guy, so he made the best possible use of LLMs — though it’s interesting to see that unlike Z80 Assembly, Claude Code really couldn’t wrap its virtual head around the UNIVAC’s assembly language, and [Nathan] had to bang out the RISC V emulator himself. Emulator in hand, [Nathan] and friends had code to run on the museum UNIVAC. A single frame of an NES game took 40 minutes, but hey, at least it finished before they got back from lunch.

[TheScienceElf]’s YouTube treatment teases hosting Minecraft, but it wasn’t a full server, just the login portion. That they were able to get TCP/IP over serial and set up a handshake between a 2020s laptop and a 1960s computer is still mighty impressive. Just the work the Vintage Computer Federation put in to get and keep this antique running is mighty impressive all on its own, but it’s wonderful they let people play with it.

Continue reading “What Can You Run On A 1960s Univac? Anything You’re Willing To Wait For!” →

A 6502 All In The Data

April 15, 2026 by Al Williams 12 Comments

Emulating a 6502 shouldn’t be that hard on a modern computer. Maybe that’s why [lasect] decided to make it a bit harder. The PG_6502 emulator uses PostgreSQL. All the CPU resources are database tables, and all opcodes are stored procedures. Huh.

The database is pretty simple. The pg6502.cpu table has a single row that holds the registers. Then there is a pg6502.mem table that has 64K rows, each representing a byte. There’s also a pg6502.opcode_table that stores information about each instruction. For example, the 0xA9 opcode is an immediate LDA and requires two bytes.

The pg6502.op_lda procedure grabs that information and updates the tables appropriately. In particular, it will load the next byte, increment the program counter, set the accumulator, and update the flags.

Honestly, we’ve wondered why more people don’t use databases instead of the file system for structured data but, for us, this may be a bit much. Still, it is undoubtedly unique, and if you read SQL, you have to admit the logic is quite clear.

We can’t throw stones. We’ve been known to do horrible emulators in spreadsheets, which is arguably an even worse idea. We aren’t the only ones.

New Display For Old Multimeter

April 14, 2026 by Bryan Cockfield 15 Comments

As a company, Fluke has been making electronic test equipment longer than the bipolar junction transistor has been around for. In that time they’ve developed a fairly stellar reputation for quality and consistency, but like any company they don’t support their products indefinitely. [ogdento] owns a Fluke meter that isn’t nearly as old as the BJT but still has an age well outside of the support window, and since the main problem was the broken LCD display they set about building a replacement for this retro multimeter.

Initially, [ogdento] had plans to retrofit this classic multimeter with a modern OLED, but could not find enough space for the display or a way to drive it easily. The next attempt to get something working was to build a custom one-off LCD using a drill press as an end mill, which didn’t work either. But after seeing a Charlieplexed display from [bobricius] as well as this video from EEVblog about designing custom LCDs, [ogdento] was able to not only design a custom PCB and LCD display to match the original meter, but was able to get a manufacturer in China to build them.

The new displays have a few improvements over the old; mostly they are more stylistically inspired by later Fluke models and have a few modern improvements to the LCD itself. There were are few issues during prototyping but nothing that was too hard to sort out, such as ordering the wrong size elastomeric strips initially. For anyone who needs to replace a custom LCD and can’t find replacement parts anymore, this project would be a great starting point for figuring out the process from the ground up.

ESP32 Weather Display Runs Macintosh System 3

April 13, 2026 by Tyler August 5 Comments

It seems like everybody takes their turn doing an ESP32-based weather display, and why not? They’re cheap, they’re easy, and you need to start somewhere. With the Cheap Yellow Display (CYD) and modules like it, you don’t even need to touch hardware! [likeablob] had the CYD, and he’s showing weather on it, but the Cydintosh is a full Macintosh Plus Emulator running on the ESP32.

The weather app is his own creation, written with the Retro68k cross-compiler, but it looks like something out of the 80s even if it’s getting its data over WiFi. The WiFi connection is, of course, thanks to the whole thing running on an ESP32-S3. Mac Plus emulation comes from [evansm7]’s Micro Mac emulator, the same one that lives inside the RP2040-based PicoMac that we covered some time ago. Obviously [likeablob] has added his own code to get the Macintosh emulator talking to the ESP32’s wireless hardware, with a native application to control the wifi connection in System 3.3. As far as the Macintosh is concerned, commands are passed to the ESP32 via memory address 0xF00000, and data can be read back from it as well. It’s a straightforward approach to allow intercommunication between the emulator and the real world.

The touchpad on the CYD serves as a mouse for the Macintosh, which might not be the most ergonomic given the Macintosh System interface was never meant for touchscreens, but evidently it’s good enough for [likeablob]. He’s built it into a lovely 3D printed case, whose STLs are available on the GitHub repository along with all the code, including the Home Assistant integration.

Who Had “New OS For The Z80” On Their 2026 Bingo Card?

April 12, 2026 by Tyler August 6 Comments

Some might say the venerable Z80 doesn’t need another operating system, but [Scott Baker] obviously disagrees. He has come up with a brand new, from scratch OS called NostOS for the Z80-based RC2014 homebrew retrocomputer. [Scott] describes it as CP/M-like, but it’s not CP/M– in fact, it’s totally incompatible with CP/M–and has a few tricks of its own up its sleeve.

As you might expect of an operating system for this vintage of hardware, it is “rommable” — that is, designed to run from read-only-memory, and fit inside 64kB. It of course supports banking memory to go higher than that 16 bit limit, and natively supports common serial devices, along with the good old WD37C65 floppy controller to get some spinning rust into the game. Of course if you don’t have floppies you can plug in a compact flash card– try that with CP/M– or, interestingly Intel Bubble Memory. [Scott] has a soft-spot for bubble memory, which at one point seemed poised to replace both hard drives and RAM at the same time. We also appreciate that he included drivers for vacuum fluorescent displays, another forgotten but very cool technology. Back in the day, this operating system would have enabled a very cool little computer, especially when you take his implementation of text-to-speech with the SP0256A-AL2 chip. Fancy a game of talking Zork? Yes, he ported Zork, and yes, it talks.

The whole thing is, of course, open-source, and available on [Scott]’s GitHub. Unlike too many open-source projects, the documentation is top-notch, to the point that we could picture getting it in a three-ring binder with a 5 1/4 floppy on the inside cover. If you like video, we’ve embedded [Scott]’s walkthrough but his blog and the docs on GitHub have everything there and more if you’re not into rapidly-flickering-pixels as an information exchange medium.

[Scott] isn’t wedded to Zilog, for the record; this OS should run on an Intel 8080, perhaps like the one in the Prompt 80 he restored last year.

Thanks to [Scott Baker] for the tip!

Continue reading “Who Had “New OS For The Z80” On Their 2026 Bingo Card?” →

Reflecting On Microsoft Windows Vista In 2026

April 9, 2026 by Maya Posch 64 Comments

It’s a bit of an understatement that at release Windows Vista rather fell flat. Much of the problem was due to how rushed of a release it was, with incomplete driver support and various glitches in the OS that ought to have been ironed out prior to release. In a retrospective, [SteelsOfLiquid] takes a look at what used to be the most infamous Windows OS until the arrival of first Windows 8 and subsequently the popcorn-fest that is Windows 11.

After a brief re-run of the development history and initial release of Vista, the OS is installed on a Core 2 Duo E8400 with 4 GB of DDR3 and a Geforce 310 card. This being the first NT6-based Windows version (with Microsoft jumping up to version 10 with Windows 10), it’s still got a lot of working software for it in 2026. Some have argued that Windows 7 is basically Vista SE in the vein of Window 98, so it doesn’t face the same software and driver hurdles as e.g. Windows XP does.

Thus the video focuses mostly on the software that was provided with the OS, giving a detailed look at an OS that many of us skipped in favor of sticking to Windows XP to the despair of Microsoft who had to push back that OS’s EOL by a few years as a result. For those of us who joined in the hate-fest against Vista it feels somewhat nostalgic to look back at an experience that in 2026 terms would have been less rough than trying to use Windows 10 or 11 until years of updates made at least the former not entirely terrible to use.

Here’s hoping that Windows 12 will be more of a modern Windows 7, especially in the GUI department, as it’s so nice to have a colorful OS interface with some tasty skeuomorphism rather than monochrome, flat icons.

Continue reading “Reflecting On Microsoft Windows Vista In 2026” →