A Computer Terminal The Old Way

Here in 2026 if we need a terminal the chances are we fire one up on our computer and continue on our way without a thought. What we are doing of course is emulating the experience of earlier hardware terminals, ones with a serial port on the back, a keyboard, a screen, or if they are a bit older, a teletype printer. [Sheila Dixon] is recreating that experience for the RC2014 retrocomputer, and she’s using some period-appropriate hardware and techniques.

Perhaps the most obvious thing about her build is her choice of printer. Sir Clive released a notoriously bad thermal printer for the ZX81, and it wasn’t long before a third-party alternative appeared in the form of the Alphacom. This printer connected directly to the ZX’s bus via its expansion port, and like the Sinclair printer, was serviced by ROM routines linked to BASIC commands. This is joined by a keyboard, first an MSX item, and then one she’s made with some retro typewriter keycaps.

She’s interfaced her Alphacom to the RC2014’s Z80 bus in the same way as it would be with the ZX81, and with a few teething troubles created some routines in a ROM to drive it as though it was the RC2014 terminal output. The keyboard is scanned using an 8255 I/O port card, much as it might have been back in the day.

If you’re curious about the Sinclair printer, we used one (without harming it!) for an April Fools’ joke during the pandemic. Meanwhile we have reviewed more than one RC2014 model, the most recent one being in 2019.

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

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!

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Decorate Your Neck With The First Z80 Badge

Over the years, we’ve brought you many stories of the creative artwork behind electronic event badges, but today we may have a first for you. [Spencer] thinks nobody before him has made a badge powered by a Z80, and we believe he may be right. He’s the originator of the RC2014 Z80-based retrocomputer, and the badge in question comes from the recent RC2014 Assembly.

Fulfilling the function of something you can write your name on is a PCB shaped like an RC2014 module, with LEDs on all the signal lines. It could almost function as a crude logic analyser for the system, were the clock speed not far too high to see anything. To fix this, [Spencer]’s badge packs a single-board RC2014 Micro with a specially slow clock, and Z80 code to step through all memory addresses, resulting in a fine set of blinkenlights.

Thus was created the first Z80-based event badge, and we’re wondering whether or not it will be the last. If you’re curious what this RC2014 thing is about, we reviewed the RC2014 Micro when it came out.

Single-Board Z80 Computer Draws Inspiration From Picasso

Picasso and the Z80 microprocessor are not two things we often think about at the same time. One is a renowned artist born in the 19th century, the other, a popular CPU that helped launch the microcomputer movement. And yet, the latter has come to inspire a computer based on the former. Meet the RC2014 Mini II Picasso!

As [concretedog] tells the story, what you’re fundamentally looking at is an RC2014 Mini II. As we’ve discussed previously, it’s a single-board Z80 retrocomputer that you can use to do fun things like run BASIC, Forth, or CP/M. However, where it gets kind of fun is in the layout. It’s the same fundamental circuitry as the RC2014, but it’s been given a rather artistic flair. The ICs are twisted this way and that, as are the passive components; even some of the resistors are dancing all over the top of one another. The kit is a limited edition, too, with each coming with a unique combination of colors where the silkscreen and sockets and LED are concerned. Kits are available via Z80Kits for those interested.

We love a good artistic PCB design; indeed, we’ve supported the artform heavily at Supercon and beyond. It’s neat to see the RC2014 designers reminding us that components need not live on a rigid grid; they too can dance and sway and flop all over the place like the eyes and or nose on a classic Picasso.

It’s weird, though; in a way, despite the Picasso inspiration, the whole thing ends up looking distinctly of the 1990s. In any case, if you’re cooking up any such kooky builds of your own, modelled after Picasso or any other Spanish master, don’t hesitate to notify the tipsline.

 

A Birthday Cake For A Retrocomputer Designer

When making a birthday cake a bit more personal, one can create a novelty themed confection appropriate for the lucky recipient. In the case of [Spencer Owen], who you may know as the creator of the RC2014 retrocomputing ecosystem, it was appropriate to have one of the little machines at work somewhere, so [peahen] did just that. The result is a cake in the shape of an IMSAI 8080 microcomputer, but it does more than just look the part. This is a working replica of the classic machine, powered as you might expect by an RC2014 sitting next to it.

The lights are a set of addressable LEDs, and the switches are made from appropriately colored sweets. Sadly the plan to make these capacitive touch switched failed as the wiring became buried in the icing, but the LEDs deserve a second look. They’re encased in translucent heatshrink sleeving which is embedded under a layer of white icing, which is translucent enough, but on top for the classic panel light look are a set of edible cake-maker’s jewels. Best of all while all except the electronics is edible, the front panel is robust enough to have been removed from the cake in one and thus will live on.

We rather like the idea of electronics meeting sugarcraft, because fondant is a surprisingly versatile medium that deserves attention much further than just confectionery. We remember it being a popular cheap way to experiment with 3D printing back at the dawn of open source printers, and it still has some potential. Meanwhile if you’ve not seen the RC2014 we reviewed its original version back in 2016, and since then it’s evolved to become an ecosystem in its own right.

No Z80? No Problem!

Earlier this year Zilog stopped production of the classic 40-pin DIP Z80 microprocessor, a move that brought a tear to the eye of retro computing enthusiasts everywhere. This chip had a huge influence on both desktop and embedded computing that lingers to this day, but it’s fair to say that the market for it has dwindled. If you have a retrocomputer then, what’s to be done? If you’re [Dean Netherton], you create a processor card for the popular RC2014 retrocomputer backplane, carrying the eZ80, a successor chip that’s still in production.

The eZ80 can be thought of as a Z80 system-on-chip, with microcontroller-style peripherals, RAM, and Flash memory on board. It’s much faster than the original and can address a relatively huge 16MB of memory. For this board, he’s put the chip on a processor daughterboard that plugs into a CPU card with a set of latches to drive the slower RC2014 bus. We can’t help drawing analogies with some of the 16-bit upgrades to 8-bit platforms back in the day, which used similar tactics.

So this won’t save the Z80, but it might well give a new dimension to Z80 hacking. Meanwhile, we’re sure there remain enough of the 40-pin chips out there to keep hackers going for many years to come if you prefer the original. Meanwhile, read our coverage of the end-of-life announcement, even roll your own silicon if you want., or learn about the man who started it all, Federico Faggin.

Addressable LEDs From A Z80

If you buy WS2812s under the Adafruit NeoPixel brand, you’ll receive the advice that “An 8 MHz processor” is required to drive them. “Challenge Accepted!“, says [ShielaDixon], and proceeded to first drive a set from the 7.3 MHz Z80 in an RC2014 retrocomputer, and then repeat the feat from a 3.5 MHz Sinclair ZX Spectrum.

The demos in the videos below the break are all programmed in BASIC, but she quickly reveals that they call a Z80 assembler library which does all the heavy lifting. There’s no microcontroller behind the scenes, save for some glue logic for address decoding, the Z80 is doing all the work. They’re all implemented on a pair of RC2014 extension cards, a bus that has become something of a standard for this type of retrocomputer project.

So the ubiquitous LEDs can be addressed from some surprisingly low-powered silicon, showing that while it might be long in the tooth the Z80 can still do things alongside the new kids. For those of us who had the Sinclair machines back in the day it’s particularly pleasing to see boundaries still being pushed at, as for example in when a Z80 was (almost) persuaded to have a protected mode.

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