8 bit

62 Articles

Three Arduinos Team Up To Make 80s-Style Computer

May 27, 2026 by 28 Comments

Back in the 80s, buying a home computer could easily mean an inflation-adjusted cost of thousands of dollars (or your equivalent currency unit of choice), and all for an 8-bit machine that might not have a hard drive and almost certainly didn’t connect to a network. Here in the future it’s easy to get spoiled by all the computing power and inexpensive devices practically falling into our laps, but using some modern low-cost microcontrollers can connect us to our early computing roots like [Joe]’s latest Arduino-based computer.

Taking design an engineering cues from computers like the Timex Sinclair 1000, Commodore PET, and TRS-80 MC-10, this computer uses a trio of Arduinos to accomplish what the best computer manufacturers once did with tons of integrated circuits. An Arduino Due handles all of the processing and traditional computing tasks, including a somewhat customized BASIC implementation, while an Uno performs audio processing duties. Taking care of the video processing is the much more capable Arduino Mega, outputting 40×25 monochrome NTSC composite video at 8×8 character resolution. There’s even WiFi courtesy of an ESP32 — certainly an upgrade compared to the source material.

After booting it up, the user gets a Commodore-like experience that replicates the 80s computing era quite well, and is even built inside its own keyboard case just like that era of computers usually were. [Joe] plans to release all three firmware images and the Python script used to get files onto the faux-retro machine, so keep an eye out for that.

In the event that you used rubles instead of dollars to pay for your expensive 8-bit machines back in the 80s, this computer might be more up your alley instead.

Remembering The BBC Computer Literacy Project

May 9, 2026 by 15 Comments

There comes a point in everybody’s life when things that they were a part of are presented as history, and for the 8-bit generation, that time is now. It’s interesting to see the early history of 8-bit home computers presented as history, not from a 2026 perspective but from the early 1990s. The BBC archive has recently posted a retrospective from 1992 looking at ten years of the Computer Literacy Project, a British government programme intended to equip the young people of the 1980s with the skills they would need to approach the information age. It’s a much more immediate history of something which was largely still in place at the time, making it a time capsule in which this past isn’t quite the other country we see it as today.

The Computer Literacy Project was run by the nation’s broadcaster and included a raft of TV programming about computers, as well as the commissioning of a machine specifically for the project. You know this machine as the Acorn BBC Micro, and aside from eventually providing the genesis of what would become ARM, it remains one of the most high-spec 8-bit machines in terms of built-in hardware. We hear from the luminaries of Acorn about the development of this machine, and then the film moves into some of the wider cultural effects.

If you were there, you’ll doubtless remember some of the TV programmes featured, and you might have used a BBC Micro at school. If you weren’t there, it’s an encapsulation of the promise on offer in that era, an optimism that seems sad when you reflect that educational computing descended into learning Microsoft Word during the following decade. It would be another two decades before the Raspberry Pi and BBC micro:bit picked up that fallen torch.

The Beeb, it seems, has long had an interest in home computers. Schools, too.

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The Atari 800

Atari Brings The Computer Age Home

January 13, 2026 by 38 Comments

[The 8-Bit Guy] tells us how 8-bit Atari computers work.

Personal Computer Market Share in 1984The first Atari came out in 1977, it was originally called the Atari Video Computer System. It was followed two years later, in 1979, by the Atari 400 and Atari 800. The Atari 800 had a music synthesizer, bit-mapped graphics, and sprites which compared favorably to the capabilities of the other systems of the day, known as the Trinity of 1977, being the Apple II, Commodore PET, and TRS-80. [The 8-Bit Guy] says the only real competition in terms of features came from the TI-99/4 which was released around the same time.

The main way to load software into the early Atari 400 and 800 computers was to plug in cartridges. The Atari 400 supported one cartridge and the Atari 800 supported two. The built-in keyboards were pretty terrible by today’s standards, but as [The 8-Bit Guy] points out there wasn’t really any expectations around keyboards back in the late 1970s because everything was new and not many precedents had been set.

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A New 8-bit CPU For C

February 21, 2025 by 61 Comments

It is easy to port C compilers to architectures that look like old minicomputers or bigger CPUs. However, as the authors of the Small Device C Compiler (SDCC) found, pushing C into a typical 8-bit CPU is challenging. Lessons learned from SDCC inspired a new 8-bit architecture, F8. This isn’t just a theoretical architecture. You can find an example Verilog implementation in the SDDC project and on GitHub. The name choice may turn out to be unfortunate as there was an F8 CPU from Fairchild back in the 1970s that apparently few people remember.

In the video from FOSDEM 2025, [Phillip Krause] provides a nice overview of the how and why of F8. While it might seem odd to create a new 8-bit CPU when you can get bigger CPUs for pennies, you have to consider that 8-bit machines are more than enough for many jobs, and if you can squeeze one into an FPGA, it might be a good choice as opposed to having to get a bigger FPGA to hold your design and a 32-bit CPU.

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Homebrew CPU Gets A Beautiful Rotating Cube Demo

February 19, 2025 by 10 Comments

[James Sharman] designed and built his own 8-bit computer from scratch using TTL logic chips, including a VGA adapter, and you can watch it run a glorious rotating cube demo in the video below.

The rotating cube is the product of roughly 3,500 lines of custom assembly code and looks fantastic, running at 30 frames per second with shading effects from multiple light sources. Great results considering the computing power of his system is roughly on par with vintage 8-bit home computers, and the graphics capabilities are limited. [James]’s computer uses a tile map instead of a frame buffer, so getting 3D content rendered was a challenge.

The video is about 20 seconds of demo followed by a detailed technical discussion on how exactly one implements everything required for a 3D cube, from basic math to optimization. If a deep dive into that sort of thing is up your alley, give it a watch!

We’ve featured [James]’ fascinating work on his homebrew computer before. Here’s more detail on his custom VGA adapter, and his best shot at making it (kinda) run DOOM.

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Retro Computer Goes Back To The 1950s

December 6, 2024 by 24 Comments

When thinking of retrocomputing, many of us will imagine machines such as the Commodore 64 or Apple II. These computers were very popular and have plenty of parts and documentation available. Fewer will go back to the Intel 8008 or even 4004 era which were the first integrated circuit chips commercially available. But before even those transistor-based computers is a retrocomputing era rarely touched on: the era of programmable vacuum tube machines. [Mike] has gone back to the 1950s with this computer which uses vacuum tubes instead of transistors.

The computer has an eight-bit architecture and features most of the components of any modern transistor-based computer of similar computational ability. Memory, I/O, an arithmetic logic unit including a carry bit that allows it to do 16-bit arithmetic, are all implemented using 6N3P dual triode tubes that date to the 50s and 60s and would have been used in similar computers like the IBM 700. All of this drives a flight simulator program or a Fibonacci number generator, demonstrating its general purpose computing capabilities.

Of course, tubes were generally phased out in favor of transistors largely due to their power and space requirements; [Mike] needs a stepladder to maintain this computer as well as around ten minutes each time he starts it up to allow the tubes to warm up, with each module needing over three amps of current each. It’s a hugely impressive build and we’d recommend checking out the video linked below to get more details on its operation. If you’re looking for something a little more accessible to get into the world of vacuum tubes, this single-board tube computer fits the bill.

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KiCad render of µLind pcb

The 6809 8-Bit Microcomputer: A Father-Son Odyssey

December 6, 2024 by 22 Comments

If you’re nostalgic for the golden age of microprocessors and dream of building your own computer, this story might spark your imagination. [Eric Lind], passionate retro enthusiast and his 14-year-old son, embarked on a mission to craft a microcomputer from scratch, centred around the exotic Motorola 6809 chip: the µLind.

What sets this project apart is its ambition: bridging retro computing with modern enhancements. Starting with just a 6809 and some basic peripherals, the men designed a multi-stage roadmap to realize their dream. Each stage brought new challenges: debugging an address decoder, reworking memory management, and evolving glue logic into programmable GAL chips. Fascinatingly, the project isn’t just about nostalgia—it’s a playground for exploring multitasking operating systems and pushing the boundaries of 8-bit computing.

Their creativity shines in solutions like a C64-compatible joystick port, add-on expansion cards, and a memory overkill of 1MB RAM. With every setback—a missing pull-up resistor or a misrouted IRQ signal—their determination grew stronger. By combining old-school know-how with modern tools like KiCad, they’ve created something that is both personal and profoundly inspiring.

[Eric]’s hope and goal is to establish a community of people that want to expand beyond the traditional Z80 and 6502 based SBC’s. Interested? Read [Eric]’s project log on Hackaday.io and start crafting!