odd inputs

4 Articles

A black OLED screen with a happy face displayed upon it is situated at the top of a squarish calculator with a 5x6 grid of white calculator keys. It floats above a graphing calculator, Nintendo Switch, aigo numpad, and an Arduino Mega on a white table. A handful of differently-colored kalih choc switches are in various places around the table.

Mechanical Switch Sci-Calc Is Also A Macropad

October 4, 2024 by 6 Comments

Smartphones have replaced a desktop calculator for most folks these days, but sometimes that tactility is just what you need to get the mathematical juices flowing. Why not spruce up the scientific calculator of yore with the wonders of modern microcontrollers?

While you won’t be able to use Sci-Calc on a standardized test, this classy calculator will let you do some pretty cool things while clacking on its mechanical choc switches. Is it a calculator? Obviously. Is it an Arduboy-compatible device that can play simple games like your TI-84? Yes. Is it also a macropad and ESP32 dev board? Why not? If that isn’t enough, it’s also takes both standard and RPN inputs.

[Shao Duan] has really made this device clean and the menu system that rewrites main.bin based on the program selection is very clever. Escape writes main.bin back into the ROM from the SD card so you can select another application. A few classic games have already been ported, and the process looks fairly straightforward for any of your own favorites.

If you’re hankering for more mathy inputs, checkout the Mathboard or the MCM/70 from 1974.

Continue reading “Mechanical Switch Sci-Calc Is Also A Macropad” →

A diagram showing an LED on the left, a lever-style plumbing valve in the center, and an Arduino Uno on the right.

Plumbing Valves As Heavy Duty Analog Inputs

October 24, 2022 by 36 Comments

Input devices that can handle rough and tumble environments aren’t nearly as varied as their more fragile siblings. [Alastair Aitchison] has devised a brilliant way of detecting inputs from plumbing valves that opens up another option. (YouTube) [via Arduino Blog]

While [Aitchison] could’ve run the plumbing valves with water inside and detected flow, he decided the more elegant solution would be to use photosensors and an LED to simplify the system. This avoids the added cost of a pump and flow sensors as well as the questionable proposition of mixing electronics and water. By analyzing the change in light intensity as the valve closes or opens, you can take input for a range of values or set a threshold for an on/off condition.

[Aitchison] designed these for an escape room, but we can see them being great for museums, amusement parks, or even for (train) simulators. He says one of the main reasons he picked plumbing valves was for their aesthetics. Industrial switches and arcade buttons have their place, but certainly aren’t the best fit in some situations, especially if you’re going for a period feel. Plus, since the sensor itself doesn’t have any moving parts, these analog inputs will be easy to repair should anything happen to the valve itself.

If you’re looking for more unusual inputs, check out the winners of our Odd Inputs and Peculiar Peripherals contest or this typewriter that runs Linux.

Continue reading “Plumbing Valves As Heavy Duty Analog Inputs” →

Custom Macro Pad Helps Deliver Winning Formulas

October 5, 2022 by 18 Comments

For those of us with science and engineering backgrounds, opening the character map or memorizing the Unicode shortcuts for various symbols is a tedious but familiar part of writing reports or presentations. [Magne Lauritzen] thought there had to be a better way and developed the Mathboard.

With more than 80 “of the most commonly used mathematical operators” and the entire Greek alphabet, the Mathboard could prove very useful to a wide number of disciplines. Hardware-wise, the Mathboard is a 4×4 macro pad, but the special sauce is in the key set implementation firmware. While the most straightforward approach would be to pick 16 or 32 symbols for the board, [Magne] felt that didn’t do the wide range of Unicode symbols justice. By implementing a system of columns and layers, he was able to get 6+ symbols per key, giving a much greater breadth of symbols than just 16 keys and a shift layer. The symbols with a dot next to them unlock variants of that symbol by double or triple-tapping the key. For instance, a lower or capital case of a Greek letter.

The Mathboard currently works in Microsoft Office’s equation editor and as a plain-text Unicode board. [Magne] is currently working on LaTeX support and hopes to add Open Office support in the future. This device was an honorable mention in our Odd Inputs and Peculiar Peripherals Contest. If you’d like to see another interesting math-themed board, check out the one on the MCM/70 from 1974.

Overwhelmed By Odd Inputs: The Contest Winners And More

July 13, 2022 by 1 Comment

The Odd Inputs and Peculiar Peripherals Contest wrapped up last week, and our judges have been hard at work sifting through their favorite projects. And this was no easy task – we had 75 entries and so many of them were cool in their own right that all we can say is go check them all out. Really.

But we had to pick winners, not the least because Digi-Key put up three $150 gift certificates. So without further ado, here are the top three projects and as many honorable mentions as you have fingers and toes – if you don’t count your thumbs.

The Prize Winners

Keybon should be a mainstream commercial product. It’s a macro keypad with an OLED screen per key. It talks to an application on your desktop that detects the program that you currently have focused, and adapts the keypress action and the OLED labels to match. It’s a super-slick 3D-printed design to boot. It’s the dream of the Optimus Maximus, but made both DIY and significantly more reasonable as a macro pad. It’s the coolest thing to have on your desk, and it’s a big winner!

On the ridiculous side of keyboards, meet the Cree-board. [Matt] says he got the idea of using beefy COB LEDs as keycaps from the bad pun in the name, but we love the effect when you press down on the otherwise blinding light – they’re so bright that they use your entire meaty finger as a diffuser. Plus, it really does look like a keypad of sunny-side up eggs. It’s wacky, unique, and what’s not to love about that in a macropad?

Finally, [Josh EJ] turned an exercise bike into a wireless gamepad, obliterating the choice between getting fit and getting high scores by enabling both at the same time. An ESP32-turned-Bluetooth-gamepad is the brains, and he documents in detail how he hooked up a homebrew cadence sensor, used the heart-rate pads as buttons, and even added some extra controls on top. Watching clips of him pedaling his heart out in order to push the virtual pedal to the metal in GRID Autosport, we only wish he were screaming “vroooom”. Continue reading “Overwhelmed By Odd Inputs: The Contest Winners And More” →