XInput is an API that is used by applications to interface with the Xbox 360 Controller for Windows. The 360 controller became somewhat of a “standard” PC gamepad, and thus many games and applications support the XInput standard.
The controller in question is the JJRC Q35-01, a trigger-type RC controller available for under $20. The conversion is executed neatly, with the original STM microcontroller being removed from the board, and the PCB traces instead being connected to a Teensy 3.5 which takes over running the show.
The conversion is remarkably complete, with the team not stopping at just reading the buttons and steering potentiometer. A USB logic analyzer was used to figure out how to control the LCD, and a calibration mode implemented just in case.
Lightsabers have enchanted audiences since their appearance in the very first Star Wars film in 1977. Unfortunately, George Lucas hasn’t shared the technology in the years since then with the broader public, so we’re left to subsist on pale imitations. This is just such a build.
The closest human analog to Jedi technology is the laser, and this build uses 8 of them in combination with two LEDs. They’re aimed to coincide at a fixed distance above the hilt. A CO2 bicycle inflater is then used to blow through an e-cigarette to create a fog. This makes the red lasers readily visible to the human eye.
This ersatz lightsaber does have its limitations – fast motion tends to scatter the fog, making it once again invisible, and it’s really at its best held in a vertical orientation. There’s also some divergence beyond the focused point. With that said, it does look somewhat impressive when held still, smouldering away.
Should you ever pick up [Steve Wozniak]’s autobiography, you will learn that in the early 1970s when his friend [Steve Jobs] was working for Atari, [Woz] was designing calculators for Hewlett Packard. It seems scarcely believable today, but he describes his excitement at the prospects for the calculator business, admitting that he almost missed out on the emerging microcomputer scene that would make him famous. Calculators in the very early 1970s were genuinely exciting, and were expensive and desirable consumer items.
[Amen] has a calculator from that period, a Prinztronic Micro, and he’s subjected it to an interesting teardown. Inside he finds an unusual modular design, with keyboard, processor, and display all having their own PCBs. Construction is typical of the period, with all through hole components, and PCBs that look hand laid rather than made using a CAD package. The chipset is a Toshiba one, with three devices covering logic, display driver and clock.
The Prinztronic is an interesting device in itself, being a rebadged 1972 Sharp model under a house brand name for the British retailer Dixons, and that Toshiba chipset is special because it is the first CMOS design to market. It was one of many very similar basic calculators on the market at the time, but at the equivalent of over 100 dollars in today’s money it would still have been a significant purchase.
It took a long time, but it’s 2019, and we’re starting to get used to the concept of talking to a computer to make it control things around the house. It’s not quite as cool as it seemed when we saw it in films way back when, but that’s just real life. The problem is, there’s a multitude of different systems and standards and they don’t all necessarily work together. In [Blake]’s case, the problem is that Woods brand hardware only works with Amazon Alexa, which simply won’t do.
[Blake] went through the hassle of getting an Amazon Alexa compatible WiFi outlet to work with Google Assistant. It’s a bit of a roundabout way of doing things, but it works. A TP-Link HS-105 WiFi plug is used, which can be controlled through Google Assistant voice commands. The part consists of two PCBs – a control board that speaks WiFi, and a switching board with relays. [Blake] used the control board and hooked it up to a Raspberry Pi. When switched on by a command from Google, the HS-105 sets a pin high, which is detected by the Raspberry Pi. The Raspberry Pi then runs a software implementation of the KAB protocol used by the Woods hardware, triggering it when it receives the signal from the TP-Link hardware.
If we understand correctly, [Blake] had to go to this trouble in order to make his special outdoor-rated outlets work with his Google Home setup. Hopefully interoperability improves in years to come, but we won’t hold our breath.
The dark, dystopian future is ever-present in the Netflix show Black Mirror, but the latest release in the series, Bandersnatch, presents a decidedly different narrative. Bandersnatch is a branching story that follows the fictional events of a garage-programmer named Stephan who develops the titular game, Bandersnatch, for the Tuckersoft company set in 1980s England. The whole thing plays out as a choose-your-own adventure game fit straight off the Sega CD (albeit with actual full motion video) by allowing watchers to pick what happens next in the story. Not one to miss a cross-promotional opportunity, Netflix also released a playable ZX Spectrum homebrew title, Nohzdyve, developed by a friend of Hackaday, [Matt Westcott].
Keen viewers of Bandersnatch were able to ascertain that the screeching sound at the end of the show when loaded into a ZX Spectrum would display a QR code. That in turn led to a real website for the fake Tuckersoft company (thankfully in HTML). The website itself showcases the fictional company’s software library and upcoming releases, but it also took things a step further. The duality of Bandersnatch is carried over to the website as there are branching paths for those that remove ‘www’ from the URL. Doing so reveals Tuckersoft’s website from an alternate timeline where Bandersnatch was never created, however, a downloadable copy of Nohzdyve in a .tap file is there for the taking.
The Nohzdyve game itself is a vertically scrolling action game that uses the ZX Spectrum’s garish color palette to great effect. Racking up a high score in the game can be done via emulator (for example Speccy) or for the most authentic experience, on real hardware. This may be the best reason to fire up a tape drive in a while, but for those seeking the less-analog approach there is always this gameplay footage from Mr. Tom FTW’s channel:
Motors are not overly complex, but this one is downright simple. Carl Bujega has been working on a motor design that heavily relies on the capabilities of the printed circuit board (PCB) fabrication processes. His talk at the 2018 Hackaday Superconference covers how he built a brushless DC motor and speed controller into a PCB. You can watch the newly published video after the break.
There are two main parts of an electric motor; the stator is stationary while the rotor spins on bearings. Electromagnetic forces are used to cause that spinning action. In this case, Carl has built the electromagnets as coils on a 4-layer circuit board (six coils on each layer). When electrified, a magnetic field is generated that pushes against the rare-earth magnets housed in the rotor.
A couple of things are really interesting here. First, those coils are usually made of “magnet wire” (enamel covered wire that is very thin) wrapped around an iron core. Using the circuit board instead saves both physical space, and the time and expense of wrapping coils of wire in the traditional way. Second, Carl has been designing with manufacture in mind; you can see in the image show that his motor design is dead-simple to assemble by inserting a 3mm bearing in the PCB, inserting magnets into the plastic rotor and snapping it into place. The end goal is to make robot actuators that are part of the circuit board itself.
The genesis of this idea came from Carl’s interest in drone design, in fact, he jumped right into a drone startup immediately after finishing his EE. The company didn’t last, but his thirst for interesting designs is ongoing. When looking at reducing the total parts necessary to build a quadcopter he happened on the idea of PCB-based coils and he’s followed it to this motor design, and beyond to some very interesting flexible-PCB robot design work which you can check out on his Hackaday.io page, YouTube, and Twitter.
There are of course some trade-offs to this. The motor is low torque since it uses an air core and not an iron core. And he’s had trouble implementing a sensor-less Electronic Speed Controller (ESC) as the back-EMF from the coils appears to be too weak. Not to fret, he added a hall sensor and has succeeded in designing an ESC that measures just 14mm by 8mm. In fact, he’s holding up the ESC and motor in the image at the top of this article!
Vacuum tubes fueled a technological revolution. They made the amplification of signals a reality for transatlantic telephone cables (and transcontinental ones too), they performed logic for early computers, and they delivered that warm fuzzy sound for high fidelity audio. But they were labor intensive to produce, and fragile, so semiconductors came along and replaced tubes in almost every application. But of course tubes are still with us and some tube applications are still critical — you’ll find them used in high-power RF and there are even satellites that depend on klystrons. So there are still experts in tube fabrication around, and Charles Alexanian is one of them. His newly-published talk at the 2018 Hackaday Supercon (found below) is a whirlwind tour of what goes into building a vacuum tube.
The process of building your own vacuum tube isn’t hard, but it’s not a walk in the park. The difficulty comes in the sheer number of processes, and the tricks of the trade found at every step. Charles’ methaphor is that if you build one tube at a time each step is like learning to ride a bicycle again, but if you build many you get into the swing of it and things go a lot better. His talk is a brief overview of everything, but if you want to drill down he also wrote an excellent article that goes further in depth.
In the working components of each tube are the precision parts: the grid (or grids). For the tube to function well these must be accurately produced which can be done with photolithography, but Charles usually uses a winding process involving a lathe. After winding, the grid is stretched to straighten the nickel wire, then cut to length. Other components such as the plate are stamped using an arbor press and simple forms he fabricates for the purpose.
Tube sealing machine common in factories
Lathe setup used for 1-off tube sealing
Tube being tested for leaks
Two glass components are used, the dome itself, and feedthrough stems that have a wire for each lead passing through a glass disc. The components are spot welded to the inside portion of the feedthrough stem, then the glass is fused together, again using a lathe. It heads over to a pumping station to evacuate the air from the tube, and is finally tested for leaks using a handheld Tesla coil (see, we knew those weren’t just toys).
Charles proposed his Supercon appearance as a chance to fabricate tubes on-site. We loved the idea, but the amount of gear needed is somewhat prohibitive (annealing ovens, vacuum cabinets, torches for sealing, and the need for 220v, plus space for it all). That’s too bad since we were really hoping to see the Jolly Wrencher in Nixie-tube form — incidentally, Charles says Nixes are simple to make compared to amplifiers and switches. He also mentions that the majority of your time is spent “washing” parts to remove impurities. Fair enough, that part sounds boring, but we hope to endure it at some point in the future because vacuum tube fabrication demos feel very much like a Hackaday event!
