Remember digital organizers? They were like the lower-spec version of a PDA that couldn’t really do much more than store a few phone numbers and calendar entries. [TundraLegendZ] recently grabbed such a device from 1995 and set about transforming it into something a little more capable.

The device in question is a Casio Business Organizer Scheduling System SF-5580. The original guts have been replaced , though, with the power of a Raspberry Pi Zero. The single-board computer is hooked up to a small color LCD screen with a resolution of 480 x 800, which is tucked neatly into the spot where the original display lived. There’s also a Raspberry Pi Pico on board, which is charged with interfacing all 82 keys of the original keyboard. Power is courtesy of a 6000 mAh battery which should last a good few hours on a single charge. Hearing the buzzer hacked is fun, too. It’s more mobile phone ringtone than outright chiptune, but we still enjoyed listening to the results. Screencaps of the software show just what this setup can do with better hardware and a nicer screen than 1995 could provide. Future work is planned to give the build more capabilities with a HackRF upgrade.

We’re not convinced anyone ever got much use out of these diminutive digital organizers, but a great many were sold in the 1990s.

hackaday.com/2026/05/18/digita…

Like many people who read Hackaday, we are fairly fluent in a number of computer languages, but we have to admit it is easier to pick up languages that look like they group with things like Fortran. Sure, modern languages have all sorts of features, but the idea that you have a text file that executes in some order, variables, statements, and so on runs through most popular languages, but not all of them. Lisp and its variants are a different way of looking at things. And then there’s Prolog. [Alexander Petros] has an interesting way of explaining Prolog as a Pokémon game.

Prolog was “the next big thing” when AI meant expert systems. It is more of a specialized database where you define facts and rules that the computer can infer answers to queries. For example, if the facts say that Paul and Anna both have Mary as a parent, and a rule says that people with the same parent are siblings, then a query asking whether Paul and Anna are siblings will indicate that they are.

How does this relate to Pokémon? The classic card game pits teams of different characters against each other, and each has particular traits and moves. Prolog is well-suited to expressing situations like this, where there are many facts and rules about how they relate to one another.

In the example, characters like Bulbasaur and Squirtle are known to be pokemon. Each character can have one or more types (e.g., Bulbasaur is both a grass and poison type). Then, rules can define things like the types of moves and traits each character has. The way Prolog works, you can provide a variable as part of a query and get lists of matches, much like a database.

We didn’t see [Alex] mention the cut operator, and many people do not like to use it. There are probably other parts of Prolog left out, too, like backtracking. However, this is as good a place to start as any, and the example is exactly the sort of problem that Prolog is good at.

If you really prefer C, you can mix C and Prolog. We can’t imagine how it worked, but there was even a computer with a Prolog operating system.

hackaday.com/2026/05/18/prolog…

Electroplating 3D prints is a good way to get a pretty nice coating on even a basic PLA part, but generally you’re expected to dunk the entire part into a big vat with electrolyte after coating it with the requisite conductive paint layer. This is great for small parts, like a ring you’d put on a finger, but gets rather silly when it’s a much larger part, such as the one in [Hendrik]’s recent video. Out of curiosity he tried to see whether rotating the part through a much smaller vat would still get you an even coating, or not.

Perhaps ironically this process required building a custom vat out of acrylic, as well as an entire rig to hold up the part and gently rotate it. This highlights the main disadvantage of this approach, in that unless you’re doing a small production run or otherwise get to re-use the rig a lot it’s a lot of extra effort.

That said, the rotation is controlled by an ESP32 and a stepper motor along with a requisite stepper driver, with the most exotic part being the whole custom PCB and enclosure, all of which can be used repeatedly. With all of that tested and confirmed working, the part to be plated was sanded, sprayed with conductive paint and hooked up to the rotating rig for an overnight run.

Following that the part’s new copper coating was polished before more layers of electroplating were applied to get the desired two different colors from different metals. Along the way no issues were found with this method of rotating electroplating, so if you regularly struggle with oversized parts to electroplate, this would seem to be a viable method.

youtube.com/embed/B2_lCMJ-_Uk?…

hackaday.com/2026/05/18/electr…