The Zilog Z80 has just turned 50 years old. This iconic 8-bit processor first went on sale in July 1976 and stayed in production for 48 years until Zilog, now a Littelfuse subsidiary, stopped accepting orders in June 2024. However, there’s an open-source replacement closer than ever to shipping in the chip’s original 40-pin DIP package thanks to community-funded fabrication.

The original Z80 packed 8,500 transistors on a 4μm process and typically ran at 2.5 MHz, with later CMOS variants reaching 20 MHz. Binary compatibility with the Intel 8080 let it absorb the existing CP/M software base, with an on-die DRAM refresh counter that cut the number of support chips a system needed. Development of working prototypes cost roughly $400,000 against $500,000 in funding from Exxon, per the Computer History Museum.

The chip powered the ZX Spectrum, TRS-80, MSX machines, Nintendo’s Game Boy, Sega’s Master System, the Pac-Man arcade cabinet, and Texas Instruments’ graphing calculators, then shipped in industrial controllers for decades after home computing moved on to more powerful successors. Zilog’s end-of-life notice, dated April 15, 2024, told customers its wafer foundry was discontinuing support for the Z84C00 family, and last-time-buy orders closed that June.

Renaldas Zioma’s FOSS Z80 project, launched shortly after the end-of-life notice, now has working silicon. The first version, fabbed on SkyWater’s 130nm node through Tiny Tapeout 7 on a die of just 0.064mm2, has been confirmed as functional via the project’s GitHub repository. A QFN64 version with all 40 pins exposed followed on the Efabless CI2406 shuttle, two further runs then went through IHP’s 130nm process, and the current run targets the classic DIP40 form factor using chip-on-board assembly on GlobalFoundries’ 180nm GF180MCU node via Wafer.Space. The end goal here is to fab a drop-in replacement for machines like the ZX Spectrum and RC2014 kits.

The design is built around Guy Hutchison’s TV80 Verilog core, and the project’s Tiny Tapeout page says the 130nm CMOS implementation should support clocks up to 50 MHz, against 4 MHz for the original NMOS part.

https://github.com/rejunity/z80-open-silicon

cross-posted from: https://slrpnk.net/post/37376302

Full construction and details at moskitos.org

Source: https://mas.to/@meganL/116471791500973082

This is one of the people/teams competing for an innovation prize at #Spezi2026. A recumbent trike you can make mostly from wood. “Open source” (I put it in quotes because I know definitions vary and I’m not clear which one this uses).

I’m told the cost was about 1,200, but that is a lot less than a similar recumbent trike with a metal welded frame would cost for materials (not to mention the labor time, skills).

Front wheel drive and the whole rear moves with the handlebars.

“Based on a concept invented more than 10 years ago by two brothers, the moskitOS tilts and turns thanks to the clever use of an articulated trapeze that allows the whole front section, including the rider, to lean when cornering! This solution also has the advantage of driving the front wheel directly, avoiding the classic long transmission chain used on almost all similar vehicles.”

cross-posted from: https://slrpnk.net/post/36451816

non YT link: https://inv.nadeko.net/watch?v=7ktbVxsL2XI

After some digging, the designs for this device are actually open source, albeit I could only find it in portuguese here

You can still use the motorcycle as usual, as it only takes 3 bolts to secure it to the cultivator

Seen that tractors and their implements are still expensive, this seems like a good alternative for small farmers

Even though I personally prefer syntropic farming systems, at least now other folks can make use of this open source hardware

From the video description:

How It Works: The motorcycle is modified with cultivation wheels positioned to align between crop rows. As the rider drives forward, the rotating tines loosen compacted soil and uproot weeds without damaging the main crops. Adjustable spacing allows adaptation to different planting layouts, ensuring precise inter row cultivation.

Advantages:

Faster than manual hoeing  
Reduces labor intensity  
Improves soil aeration  
Low fuel consumption compared to tractors  
Suitable for small and medium farms  

Disadvantages:

Requires skilled handling to avoid crop damage  
Not ideal for very narrow spacing  
Limited to relatively flat terrain  
Engine maintenance required  

Impact on Productivity: This innovation significantly boosts efficiency in crop maintenance. By mechanizing inter row cultivation, farmers can manage larger fields in less time, improve root oxygen supply, and reduce weed competition, ultimately supporting healthier crop growth and higher yields.

Suitable For:

Small scale farmers  
Vegetable and row crop cultivation  
Rural agricultural operations  
Medium sized farms seeking cost efficient mechanization  

___

Google alert: CAD files and build playlist are hosted on google services

https://www.powercircuits.nl/home/open-source-tadpole-tilting-cargo-trike

Fully Built, Open Source Design

This is an image of the final build. It looks cool and it’s great to ride (but still needs a few improvements).

The build videos playlist: https://yewtu.be/playlist?list=PL3uwHLwN7YKrodkpyXISvayLdFsccHNWB&si=lt0YrWmcryd8LzgT

CAD drawings - v7 - Feb-2026

There is a donation button on the source page as well

I don’t have to tell anyone that commercial printers suck (with the possible exception of Brother, but how long will this last?). I’ve read people on Lemmy talk about the viability of making a FOSS printer. I’d like to keep these thoughts going.

From what I remember, there are four main challenges, listed descendingly by their apparent difficulty:

1. Handling ink
2. Meeting legal regulations
3. Moving the moving parts
4. Patents

Patent difficulties indeed should be avoidable, since decent printers have been out there for way more than 20 years, the usual duration of a patent.

Moving the moving parts with the high precision necessary does at first glance seem daunting, but I’ve read people say that this is a problem many people know how to solve.

Meeting the legal obligations may ne trickier: Printer fingerprints? Aerosols? Other health and environmental hazards?

Handling ink: From what I remember, this would be the main difficulty (unfortunately I can’t find that post or comment anymore). One should avoid the problem of creating an own cartridge & nozzle production by designing the printer such that it can use an existing cartridge model (one for which there are good third-party offers). Still, one would have to solve the apparently very difficult problem that the ink/toner has to be handled under very precise conditions, regarding things like flow velocity, drying rate, and perhaps temperature.

In view of these challenges, I’ve started to think that maybe the best approach would be to try our best to find ex-employees of printer companies and convince them that they would be doing humanity a huge service if they were to contribute with whatever they legally can towards developing a FOSS printer.

Also, I’ve wondered whether the time to do this may be running out: If even Brother one day starts to crack down on third-party ink/toner, all the producers for third-party ink/toner could eventually go out of business; so that one may successfully develop a FOSS printer, only to have no other ink in the stores than the price-gouged one, which was the reason to do all this in the first place.

Do you have any corrections, specifications, or further thoughts? I’d love to hear them.

A Framework Laptop 13 with a RISC-V mainboard.