What is SpaceFN and why you should give it a try
The SpaceFN concept - setting up your space key as a layer switch when held - is probably one of the most useful tweaks in the keyboard hobby. Let me explain how it works. My SpaceFN article on kbd.news made some rounds recently - quite surprisingly given the age of this concept. This piece you're reading is a condensed version of the full post. If you're left with unanswered questions, you'll most likely find the info you're looking for in the original write-up. On my imaginary top list of the most useful keyboard features, tweaks and hacks, SpaceFN would deserve a podium finish for sure. But what makes it so special? In short: SpaceFN is easy to implement, easy to learn, costs nothing, can be used with any keyboard, and can improve your productivity instantly. I will list its benefits below, but can state right at this point that the SpaceFN concept, setting up your space key as a layer switch when held, is clearly one of the most useful tweaks in the keyboard hobby....
Apr 30, 2024
It includes some stuff for troubleshooting that can be taken out, such as a blinking heartbeat (to show it is alive) and serial debugging code.
Alternatively, you can use the github link I posted above and adapt it for a non-matrix layout. You'll be using every single I/O pin on the Pro Micro but you won't need any diodes. Wiring is simple - connect one pin of every switch to ground, and the other pin to its own digital I/O pin.
Not sure if i'm using a teensy or a pro micro or what yet though (i'll have both), but it'll be grid based.
shipping from china takes a while. Gonna start building out the actual grid tonight or tomorrow.