Odd Inputs and Peculiar Peripherals: Chorded Keyset Recreates Engelbart’s Vision

Douglas Engelbart’s 1968 “Mother of all Demos” introduced the world to a whole range of technologies we take for granted today, the most prominent being his great invention, the computer mouse. However, the MOAD also showcased things like cut-and-paste text editing, a point-and-click interface, video conferencing, and even online collaboration à la Google Docs. One of the innovations shown that for some reason didn’t stand the test of time was the chorded keyboard: an input device with five keys that can be pressed simultaneously in different combinations, the same way you would play chords on a piano.

While a handful of attempts have been made over the years to bring new life to the “chorder”, it failed to achieve mainstream appeal and remains a curiosity to this day. That makes it a natural fit for the Odd Inputs and Peculiar Peripherals contest, as we can see in [Russ Nelson]’s submission called the Engelbart Keyset, which aims to create a modern 3D printed chorder that works exactly as Engelbart intended it.

It’s important to note that the chorded keyboard was not meant to be just an additional set of five keys. Instead, Engelbart showed the clever interplay between the chorder and the mouse: the five keys under his left hand and the three mouse buttons under his right could be combined to create a full 8-bit input device. [Russ]’s device therefore includes a USB host interface to connect a USB mouse as well as a USB client interface that presents itself as a combination mouse/keyboard device to the PC.

The brains of the device are formed by a Teensy 4.1, which reads out the codes sent by the mouse as well as the five keys on top. If one or more of those keys are pressed together with a mouse button, then a keyboard code is generated corresponding to Engelbart’s original keycode mapping. We’re wondering how practical this whole setup would be in real life; it looks like something you’d have to try hands-on to find out. Fortunately, all the schematics, code and STL files are available on the project page, so with just a bit of work you can have your own MOAD setup on your desk today.

We’ve featured a couple of chorded keyboards on these pages; the Pico Chord, the Chordie and the BAT spring to mind. If you’re looking for a recap of Engelbart’s stunning presentation, check out our piece on the Mother of all Demos, 50 years on.