With customisable key mapping, this DIY keypad could be used for a wide range of purposes, such as a games controller, hotkey pad for applications, or to insert text/code snippets with a single key press.

This article first appeared in The MagPi 79 and was written by Phil King

Solderless assembly takes around 20 minutes. After attaching the supplied Pi Zero WH to an acrylic baseplate and shim, you push-fit the twelve switches into a key plate, slot that into the PCB board, then mount it on the Pi’s GPIO header.

You do need to supply your own microSD card to hold the tiny (26.6MB) Keybow OS. Upon connecting the Keybow to a computer via the USB OTG cable, the OS is loaded into a RAM disk and it boots up in a mere 10–15 seconds.

One problem we encountered was getting the USB cable to insert fully into the Pi’s USB OTG port, as it was obstructed by a thin bar on the acrylic shim – breaking that off solved the issue.

Custom keys

Once connected, the keys light up in an animated rainbow pattern (determined by a PNG file). The default key mapping is a numerical pad.

To change lighting and key mapping, you need to slot the microSD card back into your computer – there’s no way to switch instantly between them. Editing a Lua file lets you select a sample key layout or your own custom one. An online tutorial explains how.

The real power of the Keybow lies in creating advanced macros to trigger a whole series of key combinations with just a single key press – ideal for repeated key-based tasks in applications.

Verdict

8/10

A little expensive and we had problems with the USB connection, but it looks cool when lit up, the key action is good, and it could prove handy for instant key sequences.