Designing an atreus/iris-inspired keyboard - The Pteron


Not sure what you mean here. Could you perhaps make a sketch?


Yes, planned to do that anyway



Some sketches. Not perfect yet, and only one half because I accidentally deleted the other one.


Yeah, it’s much easier to edit it without the mirroring, so I usually remove the mirror first as well. It’s easy enough to add after.

The sketches show what you mean, but I don’t really know how to go from there. I tried curves like that when first starting out, but couldn’t really make anything I found attractive, so that’s why I went with the more straight/cornered style.

I might give the split case another go, and see if I can’t make something I’m happy with.


The qmk config and a default keymap for the pteron is available on my fork of qmk, and should be merged into the main qmk repo as soon as the pull request is accepted. The default keymap is largely just a copy of the default preonic keymap, with the bottom row adapted to the preonic layout.


Pteron has now been merged into QMK and is available here if anyone wants to have a look.

On a related note: It turns out that 5 rows by 12 columns is about the largest keyboard that’s possible to build using a Pro Micro, without getting into some shenanigans with the matrix. I’ve used all available pins, the only free are 3 ground pins, RAW, RESET and VCC.

#define MATRIX_ROW_PINS { D7, E6, B4, B5, B6 }
#define MATRIX_COL_PINS { F4, F6, F5, F7, B1, B3, C6, D4, D0, D1, D2, D3 }

So I got lucky when picking the number if keys I wanted on the board!


You can get larger, actually

If you make the matrix a square, or … rather 8x9 (or 9x8), you get get a lot more keys. The problem is, the traces get a lot more complicated.


Yeah, that’s what I was alluding to when I said “shenanigans”. It seems doable if using a pcb (although I wouldn’t want to be the one to figure out the layout definition), but on a handwired I think I would loose my mind trying to figure out the wiring.


lol, totally understand.

And a number of boards do this. If you look at the Planck Rev6, it does this. And most of the splits do this, as well.

But yes, it is definitely more complicated. A lot more.