Pedaling Away Under The Cover Of Your Desk

[Wayne Venables], like many of us, found himself sitting more than usual the past few months.  Armed with a Bluetooth-enabled under desk exercise bike, he quickly found the app to be rather sub-optimal and set about reverse-engineering the protocol of his bike.

Custom GUI for the exercise bike

The first step was to use some apps on his Android phone to reveal the profiles on the bike, which showed his particular machine used a Nordic Bluetooth UART. This meant the only work would be decoding the stream of bytes coming off the wireless serial port. Using Wireshark and Bluetooth logs on his phone, [Wayne] was able to correspond the various commands to points in the video. There were still a few bytes that he wasn’t able to identify, but [Wayne] had enough to whip up a quick .NET app that can start a workout and log it all to a database. The code for his app is on his GitHub.

While [Wayne] doesn’t specifically name the bike he uses in this project, we tracked down the image he shows on his writeup to the Exerpeutic 900e. It appears to be discontinued but the reverse engineering approach should be usable on a range of Bluetooth-connected machines. This isn’t the first bike we’ve seen liberated by reverse engineering here at Hackaday. And we have a feeling it won’t be the last.

Kitchen Bump Bar Plays Doom Between Orders

For as much as we love reverse engineering projects, we have to admit that we almost passed up on this “kitchen bump bar” hack. Having never had the privilege of working in the food-service industry — well, there was that time working at Chuck E. Cheese’s, but that only lasted for one shift — we were unaware of what a bump bar is, and the whys and hows of hacking one to the point where it can play Doom.

We’re glad we stuck with it, though, because [Kiwa]’s hack is pretty cool, and we got to learn a little about the technology of the modern commercial kitchen. Most fast food and family casual restaurants have what’s known as a “kitchen display system”, which relays orders from the wait staff to the kitchen. You’ve probably seen parts of the KDS, like the touch screens used by the wait staff to enter orders, or the screens dangling in the kitchen that display the pending orders. A bump bar is a small terminal used by the kitchen crew to review orders and move them around in the queue, or “bump” them, as needs dictate.

The bump bar [Kiwa] dug into appears to be a model from the early 2000s and very sturdily built, as anything used in a kitchen would need to be. Hooked up to a monitor and a keyboard, [Kiwa] discovered that it booted right into an OS with all the familiar trappings of DOS. After a detour for a teardown and dumping the flash contents, [Kiwa] was able to boot it up and run Doom, albeit somewhat slowly. It also looks like he’s got a couple of different Windows versions running, and even played some Solitaire.

It’s always fun to see what will run Doom — an NES, an oscilloscope, a thermostat, or even a bag of potatoes.

Thanks to [Fritnando] for the tip.

A HALO Of LEDs For Every Ear

Few things get a Hackaday staffer excited like bunches of tiny LEDs. The smaller and denser the better, any form will do as long as we can get a macro shot or a video of a buttery smooth animation. This time we turn to [Sawaiz Syed] and [Open Kolibri] to deliver the brightly lit goods with the minuscule HALO 90 reactive LED earrings.

The HALO 90’s are designed to work as earrings, though we suspect they’d make equally great brooches, hair accessories, or desk objects. To fit this purpose each one is a minuscule 24 mm in diameter and weighs a featherweight 5.2 grams with the CR2032 battery (2.1 g for the PCBA alone). Functionally their current software includes three animation modes, each selectable via a button on device; audio reactive, halo (fully lit), and sparkle. Check out the documentation for details on expected battery life in each mode, but suffice to say that no matter what these earrings will make it through a few nights out.

In terms of hardware, the HALO 90’s are as straightforward as you’d expect. Each device is driven by an STM8 at its maximum 16MHz which is more than fast enough to keep the 90 charliplexed 0402 LEDs humming along at a 1kHz update rate, even with realtime audio processing. In fact the BOM here is refreshingly simple with just 8 components; the LEDs, microcontroller and microphone, battery holder and passives, and the button. [Sawaiz] even designed an exceptionally slick case to go with each pair of earrings, which holds two HALO 90’s with two CR2032’s and includes a magnetic closure for the most satisfying lid action possible.

As with some of his other work, [Sawaiz] has produced a wealth of exceptional documentation to go with the HALO 90’s. They’re available straight from him fully assembled, but with documentation this good the path to a home build should be well lit and accessible. He’s even chosen parts with an eye towards long availability, low cost, and ease of sourcing so no matter when you decide to get started it should be a snap.

It was difficult to choose just a few images from [Sawaiz]’s mesmerizing collection, so if you need more feast your eyes on the expanded set after the break.

Continue reading “A HALO Of LEDs For Every Ear”

Junkbox Confidential

Thomas Edison famously quipped “To invent, you need a good imagination and a pile of junk.” Amen, brother. My personal junk pile (ahem, collection of pre-owned electromechanical curiosities) is certainly a source of spare parts, but also a source of surprise and wonder. Sometimes the junk itself spurs the imagination, but sometimes junk is just junk.

There are pieces of used gear that I bought for some particular plan, maybe a decade ago?, and totally forgot. While it’s fun to rediscover them — I bought six used super-soaker pump assemblies, and summer is just around the corner — the sad truth is often that the forgotten pieces were forgotten for a reason. Whatever kooky idea I had at the time has faded, and the parts are all that’s left.

But among these miserable creatures, there are some absolute gems. Parts that continually call out to be used. Bits that would fire even Thomas Edison’s imagination. Unforgetable junk.
Mostly, it’s their physicality that calls out to me. I have a stack of old 5″ hard drive platters, gutted, and converted into essentially a rotary encoder. For years, I used it as a USB scroll wheel on my desk, but most recently it has made reappearances in other goofy projects — a music box for my son that played notes in a row depending on how fast you spun it, and most recently a jog wheel for a one-meter linear motion project that hasn’t really found its full expression yet, but might become a camera slider. Anyway, when I needed a nice physical rotary encoder knob, the hard drive was just sitting there waiting to be used. Continue reading “Junkbox Confidential”

E.T. Video Game Gets Re-Imagined In 10 Lines Of BASIC

Most people would recognize E.T. The Extra-Terrestrial for the Atari 2600 by its reputation as one of the worst video games of all time. We’ll have more to say about that in a moment, but E.T. was nevertheless chosen as the inspiration behind [Martin Fitzpatrick]’s re-imagining of the game in ten lines of BASIC code for a contest that encourages and celebrates games written in ten lines of BASIC, or less.

Ten lines of BASIC is a big limitation, even when getting clever by stacking multiple statements into a single line, so [Martin]’s game has a much narrower scope than the original Atari 2600 version. Still, the core elements are present: E.T. must find and gather all the parts of the phone in order to contact his ship, after which he must meet the ship in time to escape. All the while, FBI agents attempt to interfere. The game was written in SAM BASIC, used by the SAM Coupé, a British Z80-based home computer from the late 80s with an emulator available for download.

Now, for lovers of “um, actually” topics, do we have a treat for you! Let’s take this opportunity to review a few things about E.T. The Extra-Terrestrial. That it was a commercial flop is no doubt, but the game itself is often badly misunderstood. Way back in 2013 we covered an extraordinary effort to patch improvements into the binary for the 2600 game, and in the process there’s a compelling case made that the game was in many ways far ahead of its time, and actually quite significant in terms of game design. You can jump right in on an analysis of the hate the game receives, and while reading that it’s helpful to keep in mind that In 1982, many of its peers were games like Space Invaders, with self-evident gameplay that simply looped endlessly.

Replacing An ESP8266 Clone With The Real Thing

The first time [konbaasiang] ordered some ceiling LED lights from Tuya, he was pleased to find they contained an ESP-12F that could easily be flashed with a different firmware. So when he ordered 30 more of them at a cost of nearly $900 USD, you can understand his frustration to find that the popular WiFi-enabled microcontroller had been swapped out for a pin-compatible clone that Tuya developed called the WB3L.

Some people would have just chalked this one up to bad luck and used the Tuya-supplied software to control their new lights, but not [konbaasiang]. Since the new chip was outwardly identical to the ESP8266, he decided to take the nuclear option and replace them with the genuine article. With a comfortable spot to work from and a nice microscope, he started on his desoldering journey.

Now it would have been nice if he could have just dropped in a real ESP-12F and called it a day, but naturally, it ended up being a bit more complex than that. The WB3L apparently doesn’t need external pull up and pull down resistors, but [konbaasiang] needed them for the swap to work. He could have come up with some kind of custom adapter PCB, but to keep things simple he decided to run a pair of through hole resistors across the top of the ESP-12F for GPIO 1/2, and use a gingerly placed SMD resistor to hold down GPIO 15.

[konbaasiang] reports that all 30 of the lights survived the transplant and are now running his own  homebrew firmware. While this story had a happy ending, it’s still a cautionary tale. With a growing trend towards replacing the venerable ESP8266 with cheaper and less hacker-friendly silicon, buying IoT hardware with the intent to replace its firmware is likely to get riskier in the near future.

Three Ways To Detect The Silver Ball

We speak from experience when we say that making pinball targets is harder than you might think. The surface area of the part of the ball that touches is oh-so-small, and you really need to have gravity on your side for best results. Luckily, [TechnoChic] did the work for us and came up with these three versatile sensor designs that would be good for any game, not just pinball. They all use fresh, pristine cardboard from the Bezos Barn and a conductive fabric tape made by Brown Dog Gadgets that they call maker tape.

With the possible exception of not being solderable (can you solder it? ours hasn’t showed up yet), maker tape is seemingly superior to copper tape because it is designed to be conductive in the Z-direction, and if you’ve ever laid out a copper tape circuit, you know that tape overlaps are pretty much par for the course.

First on the list is the track switch, which we think is pretty much necessary. After all, what fun is a pinball machine without at least one pair of rails to ride? Might as well score some points at the same time. This one looks to be the trickiest since the rails have to be consistently spaced, otherwise the ball will fall. The drawbridge target uses a cardboard hinge and the weight of the ball to force two pieces of tape together to complete the circuit.

The flappy hole target is probably our favorite because it’s the most adaptable. You could use it for all kinds of things, like getting the ball to a basement level of a pinball game, or if you want to be evil, set it up in the drain area and deduct points every time you lose the ball, or just use it to trigger the next ball to drop. This one would also be really good for something like Skee-Ball and would really keep the BoM cost down compared to say, IR break-beam targets or coin slot switches.

You can check out these sensors in a brief demo after the break, and then see how [TechnoChic] put these ideas to use in this winter-themed pinball machine we showed you a few weeks ago.

Continue reading “Three Ways To Detect The Silver Ball”