This is very much a das blinkenlights kind of project. The goal is to get a 7-segment display to count from 0 to 9, and that’s it. [Gerry] has a 74LS193 Up/Down Binary Counter, a 74LS42 BCD to Decimal Decoder, and some 74LS00 NAND gates, but he “doesn’t have” an 74LS48 to drive the 7-segment display so he emulates one with an old Altera CPLD model EPM7064SLC44 which dates back to the late nineties. A CPLD is a Complex Programmable Logic Device which is a kind of precursor to FPGA technology.
[Samcervantes] wanted a cyberdeck. Specifically, he wanted a Clockwork Pi uConsole, but didn’t want to wait three months for it. There are plenty of DIY options, but many of them are difficult to build. So [Sam] did the logical thing: he designed his own. The Bumble Berry Pi is the result.
The design criteria? A tactile keyboard was a big item. Small enough to fit in a pants pocket, but big enough to be useful. What’s more is he wanted to recycle some old Pi 3Bs instead of buying new hardware.
If you’re familiar with electrical slip rings as found in motors and the like you’ll know them as robust assemblies using carefully chosen alloys and sintered brushes, able to take the load at high RPM for a long time. But not all slip ring applications need this performance. For something requiring a lot less rotational ability, [Luke J. Barker] has something from his parts bin, and probably yours too. It’s an audio jack.
On the face of it, a 1/4″ jack might seem unsuitable for this task, being largely a small-signal audio connector. But when you consider its origins in the world of telephones it becomes apparent that perhaps it could do so much more. It works for him, but we’d suggest if you’d like to follow his example, to use decent quality plugs and sockets.
This is an entry in our 2025 Component Abuse Challenge, and we like it for thinking in terms of the physical rather than the electrical. The entry period for this contest will have just closed by the time you read this, so keep an eye out for the official results soon.
Despite the best efforts of modern medicine, Huntington’s disease is a condition that still comes with a tragic prognosis. Primarily an inherited disease, its main symptoms concern degeneration of the brain, leading to issues with motor control, mood disturbance, with continued degradation eventually proving fatal.
Researchers have recently made progress in finding a potential treatment for the disease. A new study has indicated that an innovative genetic therapy could hold promise for slowing the progression of the disease, greatly improving patient outcomes.
Ever get to the train station on time, find your platform, and then stare at the board showing your train is 20 minutes late? Bay Area Rapid Transit (BART) may run like clockwork most days, but a heads-up before you leave the house is always nice. That’s exactly what [filbot] built: a real-time arrival display that looks like it was stolen from the platform itself.
The mini replica nails the official vibe — distinctive red text glowing inside a sheet-metal-style enclosure. The case is 3D printed, painted, and dressed up with tiny stickers to match the real deal. For that signature red glow, [filbot] chose a 20×4 character OLED. Since the display wants 5 V logic, a tiny level-shifter sits alongside an ESP32-C6 that runs the show. A lightweight middleware API [filbot] wrote simplifies grabbing just the data he needs from the official BART API and pushes it to the little screen.
We love how much effort went into shrinking a full-size transit sign into a desk-friendly package that only shows the info you actually care about. If you’re looking for more of an overview, we’re quite fond of PCB metro maps as well.
Back in the innocent days of Windows 98 SE, I nearly switched to Linux on account of how satisfied I was with my Windows experience. This started with the Year of the Linux Desktop in 1999 that started with me purchasing a boxed copy of SuSE Linux and ended with me switching to Windows 2000. After this I continued tinkering with non-Windows OSes including QNX, BeOS, various BSDs, as well as Linux distributions that promised a ‘Windows-like’ desktop experience, such as Lindows.
Now that Windows 2000’s proud legacy has seen itself reduced to a rusting wreck resting on cinderblocks on Microsoft’s dying front lawn, the quiet discomfort that many Windows users have felt since Windows 7 was forcefully End-Of-Life-d has only increased. With it comes the uncomfortable notion that Windows as a viable desktop OS may be nearing its demise. Yet where to from here?
Although the recommendations from the peanut gallery seem to coalesce around Linux or Apple’s MacOS (formerly OS X), there are a few dissenting voices extolling the virtues of FreeBSD over both. There are definitely compelling reasons to pick FreeBSD over Linux, in addition to it being effectively MacOS’s cousin. Best of all is not having to deal with the Chaos Vortex that spawns whenever you dare to utter the question of ‘which Linux distro?’. Within the world of FreeBSD there is just FreeBSD, which makes for a remarkably coherent experience.
If you have a Nest thermostat of the first or second generation, you probably noticed it recently became dumber. Google decided to pull the plug on the servers that operate these devices, turning them into — well — ordinary thermostats. Lucky for us [codykociemba] has been keeping up with various exploits for hacking the thermostat, and he started the NoLongerEvil-Thermostat project.
If you want to smarten up your thermostat again, you’ll need a Linux computer or, with some extra work, a Mac. The thermostat has a DFU-enabled OMAP loader. To access it, you have to plug it into USB and then reboot it. There is a narrow window for the loader to grab it, so you have to be running the software before you reboot or you’ll miss it.
You can control your thermostat again!
After that, the flash is relatively fast, but the Nest will look dead for a brief time. Then the No Longer Evil logo will show, and you are in business. We wish the hack simply replaced the Google software with a local website, but it doesn’t. It redirects all the network traffic to a custom URL. Then you can control your thermostat from the nolongerevil.com website. So we don’t know what will happen if they decide to stop hosting the remote server that powers this. You can also run the code locally if you’ve got a server up.
If you get another year out of your trusty thermostat, that’s a year you wouldn’t have had otherwise. We do worry a bit about putting an odd device on your network. In theory, the project is open source, but all the important bits are in a binary U-Boot image file, so it would take some work to validate it. To get you started, the command to dump the content is probably: dumpimage -T kernel -p 0 -o kernel uImage. Or, you could watch it with Wireshark for a bit.
We were happy to get some more use out of our Nest.
![[Gerry] holding up a DIP IC](https://hackaday.com/wp-content/uploads/2025/11/Behind-The-Code-with-Gerry-Altera-CPLD-banner.jpg?w=600&h=450)
