Upgrade Your CoCo The Modern Way

November 12, 2026 by 1 Comment

The Radio Shack TRS-80 Colour Computer may never have achieved the sales volume of its competitors from Commodore or Apple, but it offered a surprisingly capable set of hardware. There were three versions, with the final one being a significant upgrade in many ways. There was no upgrade path for owners of version 1 and 2 machines to have a version 3 back in the day, but now thanks to [Felipe Antoniosi] such an upgrade is possible. How? With a Tang Nano 20K FPGA board, of course!

The CoCo 3 had a paged memory system for expansion up to 512k, as well as a significantly more capable graphics chip which while compatible with the original Motorola part offered enhanced graphics. The upgrade emulates these, and connects to the CoCo via a set of daughter boards that connect to where the various motherboard chips sat. it offers an HDMI output as well as analog video and enhanced sound capability, bringing the machine firmly into the 21st century.

As mods go to classic hardware, this is quite an invasive one. Whether or not you’d prefer to do this to your CoCo is up to you, but ask yourself this, would you have done this had this board been available in the 1980s? Of course you would.

Meanwhile should you become bored with the CoCo, it can also be persuaded to emulate an Apple ][.

Baochip-1x: A Mostly-Open, 22nm SoC For High Assurance Applications

November 12, 2026 by 3 Comments

For most people, just getting any old microcontroller or system on chip (SoC) from our favorite – or cheapest – vendor is more than good enough. But if you’re really into high assurance computing where every transistor has to be accounted for, you got a bit of a problem. This is basically why [Andrew “Bunnie” Huang] pitched in and had the Baochip-1x produced.

This SoC’s design is based heavily on the FPGA-based CPU in the Precursor device, which itself is claimed to be a fully verifiable communicator design. Since it does have an MMU, you can run any software on it that supports the RV32IMAC RISC-V instruction set, with a Coder’s Guide available for those who might feel interested in this SoC, along with the SystemVerilog and Verilog-based sources.

In addition to the DIY assembly process, you can even get a physical hardware version, including the ‘Dabao’ evaluation board with a very Raspberry Pi Pico-shaped form factor. Inside this SoC is a single-core, 350 MHz VexRISC-V core, 4 MB resistive RAM (RRAM) and 2 MB of SRAM, along with a whole heap of security-related features.

An INA219 board with a QWIIC connector and "female barrel jack to male barrel jack" cable soldered on. the qwiic end is plugged into the side of the Blepis PDA, with the screen showing a device found on the 0x40 address

Just Use QWIIC Already

November 12, 2026 by 10 Comments

Years ago, I wrote an article describing different I2C-on-a-connector ecosystems, explaining their strengths, weaknesses, and implementation details, as well as piling on a heap of fun stories. Looking back at it, it’s a great reference article, if I do say so myself. In particular, I highlighted QWIIC, which is a Sparkfun-borne standard for putting 3.3 V I2C on a JST-SH (or compatible) 4-pin connector.

I’ve since implemented a fair bit of QWIIC, and grew to like it so much more. I’m here to explain to you why you ought to be putting those JST-SH connectors in everything you design that touches I2C, all the cool things they let you do, where to buy a lot of cheap cables at once, and all the references you could need. I will also tell you about my USB pinout for QWIIC, something you should definitely know about.

In2ispensable Interconnect

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USB-C Hub Or Nintendo Switch 2 Dock? Relax, It’s Both!

November 12, 2026 by No comments

[Nozomi] travels with a Nintendo Switch 2, but the official dock is bulky and doesn’t seem to be made for travel. USB-C hubs with displays are common, but they won’t work with the Switch. Not without a little hacking, anyway.

It was obvious that the hub wasn’t too far off. It will charge the Switch, so Power Delivery was working. A sniffer showed that even the DisplayPort initialization happened. A little flashing on the hub allowed it to complete the proprietary protocol, and that made TV mode work, but HDR was washed out. [Nozomi] theorized it was a mismatched color space, so that required a patch for a different chip. Another flash forces the right color tag for HDR TV, but there would have to be another patch for HDR DP.

That patch doesn’t exist. Variable refresh rate also does not work. We didn’t find the actual code for the patches, but we still thought the detective work was worth the read. Some people don’t want a more portable dock, but a less portable one.

The Sextant: Navigating The Old Way

November 12, 2026 by 15 Comments

Navigation is easy these days, as we’ve entire complex computerized mapping systems and radio-based positioning systems to find ourselves anywhere on Earth. It might seem simple to use GPS these days, even trivial, but billions of dollars are what it took to make that happen.

Back in the day, navigation was simpler, and cheaper, using a handheld device and natural objects in space instead of artificial satellites with atomic clocks. Let’s learn about the sextant, and how it did its job.

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Tiny Transmitters Track Monarch Butterflies

November 12, 2026 by 7 Comments

Miniaturization is one thing, but how would you like to design a transmitter that attaches to a butterfly? That’s what the BlūMorpho transmitter is made to do, according to [Tom Jokinen] writing for Be Giant. Apparently, most of these butterflies have a two- to six-week life, but periodically a “super generation” spawns and lives up to nine months. This is enough time to migrate from Canada and the United States to Mexico. In Mexico, they spend the winter, and then return when the weather is more hospitable. Scientists wanted to study this migration pattern, and the tiny transmitter is exactly what they needed.

You can even download an app to track the butterflies yourself. The transmitter looks like a tadpole and weighs 60 milligrams. There’s no battery, but there is a tiny solar cell. The transmitter emits a Bluetooth signal that your phone’s location services can relay.

To affix the transmitter, researchers put a glassine envelope over the butterfly, weigh its wings down with something slightly heavy, and then apply eyelash glue to the transmitter. You can see the process in the video below.

What else could you do with a virtually weightless Bluetooth tracker? It is possible that dedicated tracking stations could have a longer range.

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Espresso, Meet Custom-Machined Stainless Steel Boiler

November 12, 2026 by 9 Comments

While pondering some repairs for his Gaggia Classic Pro espresso machine, [Hans Gaensbauer] ended up machining an entirely new boiler from stainless steel.

It was a nontrivial undertaking, since the boiler is an assembly that integrates not only heaters and pump connections, but one end is also the group head into which the portafilter interfaces. [Hans] had to deal with machining out the contours and pockets necessary for a portafilter to lock in securely, complete with the little screen and perforated plate responsible for even water distribution. And of course, the whole thing still has to fit into the original machine. All in all, [Hans] had some constraints to work around, making it a considerably more complex job than just milling a chamber out of a block of stainless steel.

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