Recreating A Numpad For The ADM-3A

January 8, 2023 by Matthew Carlson 1 Comment

[Evan] already had a working ADM-3A (a dumb terminal from 1976) but was starting to eye the accessories hungrily. He had only seen the numpad on Wikipedia and in the manual. So when he found some authentic stackpole numpads on a surplus sale, he grabbed them and converted them to be ADM-3A compatible.

Looking at the schematic for the ADM-3A, [Evan] figured out that the numpad was parallel to the keyboard matrix, not adjacent. This meant that pressing a five on the keyboard was electrically equivalent to pressing a five on the keyboard. So holding shift while punching on the numpad leads to some unexpected characters for those of us used to more modern keyboards. Since [Evan] only needed to make one or two of these, he soldered wires directly to switch contacts in the matrix that the ADM-3A expects. A 3d printed housing, some rubber feet, and a ribbon cable later, it was done. While it looks slightly different from the original, the vibe is right, and given that it is a stackpole switch, it has the same feel. With the spare numpads, he created a replacement PCB that runs QMK and connects to a more modern computer via USB-C. The files for the 3d printed housing are also up on GitHub, along with the PCBs and QMK configuration files.

If you’re interested in what more you can do with an ADM-3A, why not hook it up to a Raspberry Pi?

Gorgeous Sunflower Macropad Will Grow On You

January 7, 2023 by Kristina Panos 3 Comments

Once [Hide-key] saw the likes of the banana and corn macro pads, they knew they had to throw their hat in this strange and wonderful ring. Some family members suggested a sunflower, and off they went looking for inspiring images, finally settling on a more iconic and less realistic design which we think is quite beautiful.

This lovely little macro pad has seven keys hiding under those petals, with the eighth major petal concealing a XIAO RP2040 microcontroller. The rest of the major petals actuate a low-profile Kailh choc in — what else? — brown. Don’t worry, the middle isn’t a wasteland — there’s a low-profile rotary encoder underneath. Part of the reason this flower looks so great is that [Hide-key] started with SLA prints, but the paint choices are aces as well. If you’d like to grow your own sunflower, everything about this garden is open-source.

Oh yes, we totally covered the banana and the banana split, though we must have missed out on the corn. We hear that when you try it with butter, everything changes.

Via KBD #109

The Whole Thing In Python

January 2, 2023 by Elliot Williams 6 Comments

[hsgw] built a macropad in Python, and that’s not a strange language to choose to program the firmware in these days. But that’s just the tip of the iceberg. The whole process — from schematic capture, through routing and generating the PCB, and even extending to making the case — was done programmatically, in Python.

The macropad itself isn’t too shabby, sporting an OLED and some nice silkscreen graphics, but the whole point here is demonstrating the workflow. And that starts with defining the schematic using skidl, laying out the board with pcbflow, which uses a bunch of KiCAD footprints, and then doing the CAD design for a case in cadquery, which is kind of like OpenSCAD.

The result is that the whole physical project is essentially code-defined from beginning to end. We’re not sure how well all the different stages of the workflow play together, but we can imagine that this makes versioning a ton easier. Coding a PCB is probably overkill for something simple like this — you’d be faster to lay it out by hand for sure — but it doesn’t really scale. There’s definitely some level of complexity where you don’t want to be clicking an pointing, but rather typing. Think of this as the “hello world” to designing in code.

Some of the tools in the workflow were new to us, but if you’d like an in-depth look at cadquery, we’ve got you covered. [Tim Böscke]’s insane CPU made from 555 timers (yes, really) uses pcbflow. And if you’d like to dig back a bit into the origins of Python PCB design, this post introduces CuFlow, on which pcbflow was based.

The macropad PCB panel next to an assembled macropad

A Fun Low-Cost Start For Your Macropad Hobby

December 30, 2022 by Arya Voronova 7 Comments

If you were ever looking for a small relaxing evening project that you could then use day-to-day, you gotta consider the Pico Hat Pad kit by [Natalie the Nerd]. It fits squarely within the Pi Pico form-factor, giving you two buttons, one rotary encoder and two individually addressable LEDs to play with. Initially, this macropad was intended as an under-$20 device that’s also a soldering practice kit, and [Natalie] has knocked it out of the park.

You build this macropad out of a stack of three PCBs — the middle one connecting the Pi Pico heart to the buttons, encoders and LEDs, and the remaining ones adding structural support and protection. All the PCBs fit together into a neat tab-connected panel — ready to be thrown into your favorite PCB service’s shopping cart. Under the hood, this macropad uses KMK, a CircuitPython-based keyboard firmware, with the configuration open-source. In fact everything is open-source, just the way we like it.

If you find yourself with an unexpected affinity for macropads after assembling this one, don’t panic. It’s quite a common side-effect. Fortunately, there are cures, and it’s no longer inevitable that you’ll go bananas about it. That said, if you’re fighting the urges to go bigger, you can try a different hand-wireable Pico-based macropad with three more keys. Come to find that one not enough? Here’s a 2×4 3D printable one.

Now, if you eventually find yourself reading every single Keebin’ With Kristina episode as soon as it comes out, you might be too far gone, and we’ll soon find you spending hundreds of dollars building tiny OLED screens into individual keys — in which case, make sure you document it and share it with us!

Continue reading “A Fun Low-Cost Start For Your Macropad Hobby” →

Mouse Enjoys Its Freedom

December 28, 2022 by Bryan Cockfield 29 Comments

Although it took a little while to standardize on the two-button-with-scroll-wheel setup, most computers have used a mouse or mouse-like device to point at objects on the screen since the 80s. But beyond the standard “point and click” features of the mouse, there have been very few ground-breaking innovations beyond creature comforts. At least, until the “Space Mushroom” mouse from [Shinsaku Hiura] hit our tips line.

This mouse throws away most of the features a typical mouse might have in favor of a joystick-like interface that gives it six degrees of freedom instead of the usual two — while still being about mouse-sized and held in the hand. It doesn’t even have a way of mapping motion directly to movements on the screen. Instead, it maps each degree of freedom to a similar movement of the mouse itself using these three joystick sensors physically linked together, with some underlying programming to translate each movement into the expected movement on the screen.

While this might not replace a standard mouse for every use case anytime soon, it does seem to have tremendous benefit in 3D modeling software, CAD, or anything where orienting a virtual object is the primary goal. Plus, since there’s no limit to the number of mice that can be attached to a computer (beyond USB limitations) this mouse could easily be used in conjunction with a normal mouse much like macro keyboards being used alongside traditional ones.

Continue reading “Mouse Enjoys Its Freedom” →

All About USB-C: Illegal Adapters

December 27, 2022 by Arya Voronova 107 Comments

Let’s be clear – it’s not enough to have USB-C to USB-C cables. There’s a lot of cables that we might want to acquire for our day-to-day use, perhaps, for a transition period while we still own some amount of devices not adorned with a USB-C connector. However, the USB-C specification only accounts for a limited amount of kinds of cables, explicitly or implicitly excluding a range of cables that you might want to buy or make.

It’s my firm belief that, as a hacker, you should be able to buy any USB-C contraption that you could ever need. Hackers don’t need restrictions driven by marketing – they need understanding of how a piece of tech can or cannot be used, based on how it operates internally. I would like you to provide with such understanding, so that you can make informed decisions.

On the other hand, USB-C is designed to be used by less-than-skilled people, even if it often fails at that. (Cable labelling, anyone?) Clear definitions of what complies to a standard can help enforce it. Here’s the notorious story of a USB-C cable that killed a Chromebook, and launched a career of explaining USB-C specifics online for [Benson Leung]. There’s many such failure stories, in fact. Today, we’ll go through USB-C contraptions which might or might not fail you, depending on how you use them. Continue reading “All About USB-C: Illegal Adapters” →

An exercise bike modified to become a game controller

Pedal Your Way Through Games With This USB Exercise Bike

December 26, 2022 by Robin Kearey 13 Comments

If you’re into cycling, there’s nothing better than heading out on the open road and feeling the wind in your hair. Unfortunately, climatic conditions make this uncomfortable or impossible at certain times of year, so you might be tempted to stay inside and play video games instead. Luckily, you can now get your gaming fix and still get in shape thanks to [Patrick]’s exercise bike game controller.

[Patrick] got himself a second-hand exercise bike and discovered that the speed sensor inside it was based on a magnet and reed relay, just like a regular bike computer. Reading out the sensor was therefore as simple as counting pulses using an Arduino Leonardo, and the USB HID protocol made it easy to turn the cycling mechanism into a one-dimensional game controller.

He then completed the setup by adding two 3D-printed handlebar-mounted gamepads with a few buttons and a thumbstick on each side. The total system now works as an ordinary gamepad, but with the option of using the bike as a forward/backward control.

We can imagine that this system will stay interesting for far longer than any off-the-shelf internet-connected exercise bike, because you can interface it with basically any game. [Patrick] demos his rig using first-person shooters like Doom and Team Fortress 2, but the possibilities are endless: how about turning FIFA games into bike polo? Or Mirror’s Edge into a bicycle courier adventure? After all, we’ve already seen how a similar game controller can turn Grand Theft Auto into something more like Grand Theft Bicycle.

Continue reading “Pedal Your Way Through Games With This USB Exercise Bike” →