Look mum, no Pro Micro

A project log for Aerodox

[WIP] Keyboard based on Ergodox. But wireless?

simon-merrettSimon Merrett 01/04/2022 at 22:390 Comments

I'm pleased to say that, albeit not perfectly implemented, I have managed to turn #Aerodox into the project it was always supposed to be by getting it to work on more than one PC.  #Aerodox 's layout is based on Ergodox but it's circuitry is based on the #Redox keyboard 's wireless version. This was deliberately because Mattia Dal Ben had done a great job implementing a wireless keyboard and also documenting it. The internals of the wireless Redox were a clear analogue that showed me what I wanted probably lay down that path. 

Unfortunately, it would need a receiver on each PC, as well as a Gazell protocol channel hopping scheme that you would need to switch over on both halves of the keyboard. After making the changes to boost the voltage on the motherboards, I was using Aerodox daily and knew I wanted to make a move to use it on my other PC(s). But one thing was niggling me - someone had managed to get bluetooth working on the Mitosis, the keyboard that I think inspired the Redox wireless and they now had a small keyboard that had a Gazell link between the halves and bluetooth from one half back to the PC. 

The icing on the cake for me was that they were able to switch between 3 different PCs using the bluetooth. For the last two days I have been trying adapt the Bluetosis code to work on #Aerodox and tonight I finally got it working. I'm so chuffed I can switch between my two main PCs with a press of this little button:

There are kinks to iron out. Firstly, I had to ditch the way timer interrupts and debouncing is done in the Redox way and I think I have taken a hit on responsiveness to key presses on the right (bluetooth/Gazell host) half. But I'm optimistic that I'll be able to tweak that. For example, there is an 8Hz Gazell message transmission that the left half sends until it goes to sleep after 500ms and I think the new scheme could potentially do away with that, freeing up buffer-transfers on the host side.

Other things that other people may not like is that although the keymaps are qmk-like, nothing is running qmk any more (it was on the pro-micro connected to / built into the Redox wireless receiver). I don't care as I can press all the keys I want to!

Other than optimising the responsiveness, what else is there to do with Aerodox? Well this recent foray has given me more confidence to navigate Nordic chips and tools, and with ZMK up-and-coming, perhaps we'll see an NRF52 version of #Aerodox one day. 

Also, you can't go your whole life wondering if the first split ortholinear ergo key layout you picked was the best one, when there are so many to try...