I guess these are questions for @mntmn, but I figured I’d ask here in case others are interested or know the answers…
I’m looking into building a custom keyboard for my Reform, and I noticed there’s now a reform2-keyboard3-pcb source dir, and some recent social media posts about the v3 keyboard .
I’m trying to figure out if I should base my design on the original reform2-keyboard-pcb project, or the new reform2-keyboard3-pcb. (Traditional stagger is one of the changes I want. I also don’t care (at least to start with) if there are gaps at the sides from not having 1.75U keycaps, etc.)
Is the keyboard3 design stable and suitable for getting fabbed, or is there still more work to be done? I see the commit message says “initial design”, and that the files have the traditional stagger and holes for the 2U stabilizer - but not the “standalone vs laptop switch” mentioned on mastodon. Is there a later version than what’s in the gitlab - and if so, can it be made available? I’d rather not go to the effort of modifying a design which is going to get other improvements soon…
I also notice that it’s still using the ATMEGA32U4-AU - which are thankfully back in stock. But the Pocket Reform’s keyboard is using RP2040 (and the Reform trackball module also got converted to RP2040). Are there any plans for reform2-keyboard3 to use RP2040 in the near future? I’m fine if not, but in that case I’ll order some ATMegas soon (to avoid any possibility of them going out of stock again).
The most important parts of a custom reform keyboard are the physical size, and the connectors. So long as you match those (and on all the alternative keyboards you mentioned I imagine they’re exactly the same), it’s just a matter of writing keyboard firmware that plays nicely with the system controller.
That said, I’m not sure if there exists any firmware yet for non-atmega based keyboard? I didn’t see any in the reform repo from a quick glance, so maybe minute is still working on it.
It’s the Pocket Reform which is using the RP2040 (pcb and fw). I don’t think it directly translates to the Reform, since the keyboard layout is different, it’s a merged keyboard/trackball, and has RGB LEDs. My guess is that eventually the Reform’s keyboard will get converted to RP2040, but there’s no longer any urgency since the ATMegas are available again.
In terms of the reform2-keyboard-pcb vs reform2-keyboard3-pcb dirs, after figuring out how to have multiple copies of KiCad open, I visually compared their schematics and PCBs, and was able to confirm that (currently at least) the only difference is to accommodate the adjusted key layout. I assume this means that any further changes (eg. switch for standalone vs laptop) haven’t been uploaded because they’re not ready yet.
My plan is definitely “just” to rearrange the physical layout, reusing the original firmware (ISTR people having difficulties hacking QMK etc to talk to the LPC/OLED, and have the reform-specific menu). That said, I’m trying a pretty ambitious “rearrangement” - the MCU and other stuff will be on a small separate board (in the empty space above the SD card slot), that’s connected by FFC to the matrix of switches on the “actual keyboard”. The hope is that this will make it easier for me (and others) to quickly and easily try out various alternative keyboard layouts - since you only have to worry about making a simple board that connects the keys to the FFC connector, while the controller board stays the same (perhaps reflashed for adjusted col/row pin assignments). I’ve designed an initial version of the controller PCB (literally by removing the switch matrix and then rearranging what remained) and now waiting for it to be made.
I’m a little concerned about RFI from the FFC - especially the powered PWM WLED lines (but for now I can just ignore and not connect the WLED FFC, if necessary). Anyway, my next steps are to order parts, and design one (or maybe more?!) “matrix” layout PCBs (by taking the MCU etc off the OG board) and get them made too.