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Considering their hardware specification, graphing calculators surely feel like an anachronism in 2019. There are plenty of apps and other software available for that nowadays, and despite all preaching by our teachers, we actually do carry calculators with us every day. On the other hand, never underestimate the power of muscle memory when using physical knobs and buttons instead of touch screen or mouse input. [epostkastl] combined the best of both worlds and turned his broken HP-48 into a Bluetooth LE keyboard to get the real feel with its emulated counterpart.

Initially implemented as USB device, [epostkastl] opted for a wireless version this time, and connected an nRF52 based Adafruit Feather board to the HP-48’s conveniently exposed button matrix pins. For the software emulation side, he uses the Emu48, an open source HP calculator emulator for Windows and Android. The great thing about Emu84 is that it supports fully customizable mappings of regular keyboard events to the emulated buttons, so you can easily map, say, the cosine button to the [C] key. The rest is straight forward: scanning the button matrix detects button presses, maps them to a key event, and sends it as a BLE HID event to the receiving side running Emu84.

As this turns [epostkastl]’s HP-48 essentially into a regular wireless keyboard in a compact package — albeit with a layout that outshines every QWERTY vs Dvorak debate. It can of course also find alternative use cases, for examples as media center remote control, or a shortcut keyboard. After all, we’ve seen the latter one built as stomp boxes and from finger training devices before, so why not a calculator?

Many people enjoy playing flight simulators or making the occasional orbit in Kerbal Space Program, but most are stuck controlling the onscreen action with nothing more exotic than a keyboard and mouse. A nice compromise for those that don’t have the space (or NASA-sized budget) to build a full simulator cockpit is a USB “button box” that you can plug in whenever you need a couple dozen extra knobs, switches, and lights.

If you’ve been considering building one for yourself, this incredible build by [nexprime] should prove quite inspirational. Now at this point, a box of buttons hooked up to a microcontroller isn’t exactly newsworthy. But there are a few features that [nexprime] packed in which we think make this particular build worth taking a closer look at.

For one, the powder coated 8.5” x 10” enclosure is absolutely gorgeous. The console itself was purchased from a company called Hammond Manufacturing, but of course it still took some work to turn it into the object you’re currently drooling over. A CNC machine was used to accurately cut out all the necessary openings, and the labels were laser etched into the powder coat.

But not all the labels. One of the things we like best about this build is that [nexprime] thought ahead and didn’t just design it for one game. Many of the labels are printed on strips of paper which slide into translucent plastic channels built into the front of the box. Not only does this allow you to change out the overlays for different games, but the paper labels look fantastic when lit with the LED strips placed behind the channels.

Internally, [nexprime] used a SparkFun Pro Micro paired with a SX1509 I/O expander. The electronics are all housed on professionally manufactured PCBs, which gives the final build an incredibly neat look despite packing in 68 separate inputs for your gaming pleasure. On the software side this box appears as a normal USB game controller, albeit one with a crazy number of buttons.

If this build doesn’t have enough switches and buttons for you, don’t worry. This Kerbal Space Program cockpit has banks of switches below and above the player, so one can more realistically scramble for the correct onet to flip when things start going sideways. On the other hand, we’ve seen slightly less intense builds if you’re not quite ready to take out a loan just to get into orbit.

In the era of touch screens and capacitive buttons, we’d be lying if we said we didn’t have the occasional pang of nostalgia for the good old days when interfacing with devices had a bit more heft to it. The physical clunk and snap of switches never seems to get old, and while you can always pick up a mechanical keyboard for your computer if you want to hear that beautiful staccato sound while firing off your angry Tweets, there’s a definite dearth of mechanical interface devices otherwise.

[Jeremy Cook] decided to take matters into his own hands (literally and figuratively) by designing his own multipurpose USB rotary input device. It’s not a replacement for the mouse or keyboard, but a third pillar of the desktop which offers a unique way of controlling software. It’s naturally suited to controlling things like volume or any other variable which would benefit from some fine tuning, but as demonstrated in the video after the break even has some gaming applications. No doubt the good readers of Hackaday could think of even more potential applications for a gadget like this.

The device is built around the diminutive Arduino-compatible PICO board by MellBell, which features a ATmega32u4 and native USB. This allowed him to very rapidly spin up a USB Human Interface Device (HID) with minimal headaches, all he had to do was hang his buttons and rotary encoder on the PICO’s digital pins. To that end, he [Jeremy] used the fantastic I2C rotary encoder designed by [fattore.saimon], which readers may remember as a finalist in the Open Hardware Design Challenge phase of the 2018 Hackaday Prize. He also added a NeoPixel ring around the encoder to use for some visual feedback and because, well, it just looks cool.

Since all of the core components are digital, there’s not a whole lot required in the way of wiring or passive components. This let [Jeremy] put the whole thing together on a piece of perfboard, freeing him up to spend time designing the 3D printed enclosure complete with translucent lid so he can see the NeoPixel blinkenlights. He got the tolerances tight enough that the whole device can be neatly press-fit together, and even thought to add holes in the bottom of the case so he could push the perfboard back out if he needed to down the line.

[Jeremy] spends a good chunk of the video going over the software setup and development of the firmware, and details some of the nuances he had to wrap his head around when working with the I2C encoder. He also explains the math involved in getting his encoder to emulate a mouse cursor moving in a circle, which he thinks could be useful when emulating games that originally used an encoder such as Tempest or Pong.

We’ve seen similar USB “knobs” in the past for controlling volume, but the additional inputs that [Jeremy] built into his version definitely makes it a bit more practical. Of course we’re suckers for interesting USB input devices to begin with.

Puff and Suck (or Sip and Puff) systems allow people with little to no arm mobility to more easily interact with computers by using a straw-like unit as an input device. [Ana] tells us that the usual way these devices are used to input text involves a screen-based keyboard; a cursor is moved to a letter using some method (joystick, mouse emulator, buttons, or eye tracking) and that letter is selected with a sip or puff into a tube.

[Ana] saw such systems as effective and intuitive to use, but also limited in speed because there’s only so fast that one can select letters one at a time. That led to trying a new method; one that requires a bit more work on the user’s part, but the reward is faster text entry. The Puff-Suck Interface for Fast Text Input turns a hollow plastic disk and a rubber diaphragm into bipolar pressure switch, able to detect three states: suck, puff, and idle. The unit works by having an IR emitter and receiver pair on each side of a diaphragm (one half of which is shown in the image above). When air is blown into or sucked out of the unit, the diaphragm moves and physically blocks one or the other emitter-receiver pair. The resulting signals are interpreted by an attached Arduino.

How does this enable faster text input? By throwing out the usual “screen keyboard” interface and using Morse code, with puffs as dots and sucks as dashes. The project then acts as a kind of Morse code keyboard. It does require skill on the user’s part, but the reward is much faster text entry. The idea got selected as a finalist in the Human-Computer Interface Challenge portion of the 2018 Hackaday Prize!

Morse code may seem like a strange throwback to some, but not only does the bipolar nature of [Ana]’s puff-suck switch closely resemble that of Morse code input paddles, it’s also easy to learn. Morse code is far from dead; we have pages of projects and news showing its involvement in everything from whimsical projects to solving serious communication needs.

While the vast majority of us are content to plod along with the squishy chiclet keyboards on our laptops, or the cheapest USB membrane keyboard we could find on Amazon, there’s a special breed out there who demand something more. To them, nothing beats a good old-fashioned mechanical keyboard, where each key-press sounds like a footfall of Zeus himself. They are truly the “Chad” of the input device world.

But what if even the most high end of mechanical keyboards doesn’t quench your thirst for spring-loaded perfection? In that case, the only thing left to do is design and build your own. [Matthew Cordier] recently unveiled the custom mechanical keyboard he’s been working on, and to say it’s an elegant piece of engineering is something of an understatement. It may even better inside than it does on the outside.

The keyboard, which he is calling z.48, is based around the Arduino Pro Micro running a firmware generated on kbfirmware.com, and features some absolutely fantastic hand-wiring. No PCBs here, just a rainbow assortment of wire and the patience of a Buddhist monk. The particularly attentive reader may notice that [Matthew] used his soldering iron to melt away the insulation on his wires where they meet up with the keys, giving the final wiring job a very clean look.

Speaking of the keys, they are Gateron switches with DSA Hana caps. If none of those words mean anything to you, don’t worry. We’re through the Looking Glass and into the world of the keyboard aficionado now.

Finally, the case itself is printed on a CR-10 with a 0.3 mm nozzle and 0.2 mm layers giving it a very fine finish. At 70% infill, we imagine it’s got a good deal of heft as well. [Matthew] mentions that a production case and a PCB are in the cards for the future as he hopes to do a small commercial run of these boards. In the meantime we can all bask in the glory of what passes for a prototype in his world.

We’ve seen some exceptionally impressive mechanical keyboards over the years, including the occasional oddity like the fully 3D printed one and even one that inexplicably moves around. But this build by [Matthew] has to be one of the most elegant we’ve ever come across.

[Thanks to DarkSim905 for the tip]

If you have even the most passing interest in space and what it takes to get there, you’ve probably already played Kerbal Space Program (KSP). If you haven’t, then you should set aside about ten hours today to go check that out real quick. Don’t worry, Hackaday will still be here when you get back. Right now you need to focus on getting those rockets built and establishing a network of communication satellites so you can get out of low orbit.

For those of you who’ve played the game (or are joining us again after playing KSP for the prescribed 10, 12, 16 hours), you’ll know that the humble computer keyboard is not very well suited to jaunts through space. You really want a joystick and throttle at the absolute minimum for accurate maneuvers, but even you’ll be spending plenty of time back on the keyboard to operate the craft’s various systems. If you want the ultimate KSP control setup, you’ll need to follow in the footsteps of [Hugo Peeters] and build your own. Luckily for us, he’s written up an exceptionally well detailed guide on building KSP controllers that should prove useful even if you don’t want to clone his.

Wiring switches and buttons to the Arduino.

At the most basic level, building a KSP controller consists of hooking a bunch of switches and buttons to a microcontroller such as the Arduino or Teensy, and converting those to USB HID key presses that the game understands. This works fine up to a point, but is limited because it’s only a one-way method of communication. For his controller, [Hugo] forked KSPSerialIO, a plugin for KSP that allows bidirectional communication between the game and your controller, enabling things like digital readouts of speed and fuel levels on the controller’s panel.

Once the logistics of how you’ll talk to the game are settled, the rest is really up to the individual. The first step in building your own KSP controller is deciding what you want it to do. Are you looking to fly planes? Control a rover? Maybe you just want a master control panel for your space station. There’s a whole lot of things you can build in KSP, and the layout, inputs, and displays on your controller should ideally reflect your play style.

[Hugo] went with a fairly general purpose panel, but did spend quite a bit of extra time to get some slick LED bar graphs hooked up to display resource levels of different systems on his craft. That’s an extra step that isn’t strictly required for a build like this, but once you see it, you’re going to have a hard time not wanting to include it on your own panel. He also went through the expense of having the panel and case professionally laser cut and etched, which definitely gives it a polished feel.

We’ve covered quite a number of custom KSP controllers here at Hackaday. The overlap between KSP players and hackers seems unusually high, but of course a game that lets you build and fly contraptions of your own design does sound like something that would be right up our alley.

Keyboards are currently the most universally accepted computer input devices. They may be wired, wireless, or virtual, but the chances are that you’re within a few centimeters of a keyboard right now. [Federico Terzi] built a prototype from an Arduino and an accelerometer which conceptually resembles writing in Palm’s old Graffiti, though this version is performed in mid-air with a handheld instead of a little square at the bottom of an LCD screen.  He can also operate wirelessly with a Bluetooth module and battery.

The task of the Arduino is to take data from the accelerometer and feed it to the computer whenever a 12mm switch is pressed. Each letter is individually learned by his Python code and scikit-learn’s Support Vector Machine. There’s nothing holding a user back from giving single-letter commands to your favorite programs. For example, it would be possible to give a thumbs-up in meatspace when you want to upvote or covering your ears could mute the audio.

We love keyboard hacks like this mechanical macro keyboard, a minimal and elegant USB Morse key(board), and Brian Benchoff’s open love-letter to mechanical keyboards.

Thank you, [Juan Pablo] for the tip.


Filed under: Arduino Hacks, Peripherals Hacks

Working with CAD programs involves focusing on the task at hand and keyboard shortcuts can be very handy. Most software packages allow the user to customize these shortcuts but eventually, certain complex key combination can become a distraction.

[awende] over at Sparkfun has created a Cherry MX Keyboard which incorporates all of the Autodesk Eagle Shortcuts to a single 4×4 matrix. The project exploits the Arduino Pro Mini’s ability to mimic an HID device over USB thereby enabling the DIY keyboard. Pushbuttons connected to the GPIOs are read by the Arduino and corresponding shortcut key presses are sent to the host machine.

Additional functionality is implemented using two rotary encoders and the Teensy encoder library. The first knob functions as a volume control with the push-button working as a mute button. The encoder is used to control the grid spacing and the embedded button is used to switch between imperial and metric units. The entire code, as well as the schematic, is available on GitHub for your hacking pleasure. It’s a polished project just ready for you to adapt.

The project can be extended to be used with other computer software such as Gimp and the keys may be replaced by capacitive touch sensors making it more sturdy. Bluetooth can be added to make things wireless and you can check out the Double Action Keyboard to extend functionality further.


Filed under: Arduino Hacks, peripherals hacks

You’re not cool unless you have a mechanical keyboard. Case in point: if you were to somehow acquire an identical keyboard to the one I used to type this, it would set you back at least seven hundred dollars. Yes, it’s mechanical (Topre), and yes, I’m cooler than you. Of course, you can’t be as cool as me, but you can build your own mechanical keyboard. [Robin] is, I presume, a pretty cool dude so he built his own keyboard. It’s the amazing shortcut keyboard, and it can be programmed graphically.

The idea for this keyboard came when [Robin] was studying as an engineer. We assume this is code for wearing out the Escape key on AutoCAD, but many other software packages have the same problem. The solution to [Robin]’s problem was a shortcut keypad, a 3 by 4 matrix of Cherry switches that could be programmed for any task.

The design of this keyboard started out as an Adafruit Trellis matrix keypad. This was combined with some software written in Processing that assigned macros to each button. This was a sufficient solution, but the switches in the Adafruit trellis look squishy. These are not the right switches for someone who craves a soft snap under every fingertip. It’s not the keyboard of someone who desires the subtle thickness of laser etched PBT keycaps. The Adafruit keypad doesn’t have the graceful lines of a fully sculpted set of keycaps. Oh my god, it’s doubleshot.

[Robin]’s completed keyboard has gone through a few revisions, but in the end, he settled on PCB-mounted switches and a very clever 3D printed standoff system to hold an Arduino Pro Micro in place. The enclosure, too, is 3D printed, and the end result is a completely custom keyboard that’s perfect for mashing key combos.

You can check out a video of this keyboard in action below.


Filed under: Arduino Hacks, peripherals hacks

MalDuino is an Arduino-powered USB device which emulates a keyboard and has keystroke injection capabilities. It’s still in crowdfunding stage, but has already been fully backed, so we anticipate full production soon. In essence, it implements BadUSB attacks much like the widely known, having appeared on Mr. Robot, USB Rubber Ducky.

It’s like an advanced version of HID tricks to drop malicious files which we previously reported. Once plugged in, MalDuino acts as a keyboard, executing previous configured key sequences at very fast speeds. This is mostly used by IT security professionals to hack into local computers, just by plugging in the unsuspicious USB ‘Pen’.

[Seytonic], the maker of MalDuino, says its objective is it to be a cheaper, fully open source alternative with the big advantage that it can be programmed straight from the Arduino IDE. It’s based on ATmega32u4 like the Arduino Leonardo and will come in two flavors, Lite and Elite. The Lite is quite small and it will fit into almost any generic USB case. There is a single switch used to enable/disable the device for programming.

The Elite version is where it gets exciting. In addition to the MicroSD slot that will be used to store scripts, there is an onboard set of dip switches that can be used to select the script to run. Since the whole platform is open sourced and based on Arduino, the MicroSD slot and dip switches are entirely modular, nothing is hardcoded, you can use them for whatever you want. The most skilled wielders of BadUSB attacks have shown feats like setting up a fake wired network connection that allows all web traffic to be siphoned off to an outside server. This should be possible with the microcontroller used here although not native to the MalDuino’s default firmware.

For most users, typical feature hacks might include repurposing the dip switches to modify the settings for a particular script. Instead of storing just scripts on the MicroSD card you could store word lists on it for use in password cracking. It will be interesting to see what people will come up with and the scripts they create since there is a lot of space to tinker and enhanced it. That’s the greatness of open source.

You can watch the prototype in action in the video:


Filed under: Arduino Hacks, peripherals hacks, security hacks


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