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Hello to all keyboard enthusiast here on the Fédiverse.
For the longest time, I have used a TypeMatrix 2030 as my daily driver, most of which was spent daydreaming of finding a close approximation that would be mechanical. Failing to find one, I procrastinated in researching how I could build my own, which was an error.
Now, my good old TypeMatrix is showing signs of dying, and I still don’t have even started on its mechanical replacement. So, I would like help and counsel on how to make one.
I don’t need it to be identical, (I don’t need the rightmost column on the actual TypeMatrix, for example) but I DO need the middle column with “del”, “backspace” and “enter” keys.
Would anyone be willing to help me, please?
No problem, glad to help point you in a useful direction. If you're not especially concerned with labels, you might be able to get around needing to have a blank set of keycaps laser etched or something like that.
I also got bored yesterday and had your idea of a TypeMatrix 2030 kicking around my head, so I decided to mock-up a layout similar to what I described in the previous post, and created a Github project you can use as a jumping off point if you want to proceed that direction.
https://github.com/pyunramura/mechamatrix2030
Keep in mind, the layout probably needs some more thought and the pcb generation part of it has not even been started, but it should be possible to get a completed board with some learning, some funds, and some work.
One of the major issues I didn't think of before is the fact that the keyboard has quite a lot of keys, so many in fact that the matrix is too large for a standard pro-micro type microcontroller. The keyboard has 7 rows and 15 columns which needs 22 pins, which is unfortunately 4 too many for a pro-micro. There are other microcontrollers with a similar footprint that might be suitable instead though. Elite-C, Blackpill, and some of the RP2040 boards come to mind.
Thanks for your great work.
Concerning the lacks of pin on some controllers, the function row could always be folded in the numbers row and made acessible via a function key of some sort.
We could also make it so pressig the two shift buttons simultaneously is how you lock into upper-case letters. (Another double-shift to unlock.) That would let us remove the rightmost colum too. (I only need the upper-case lock from it, and I don't need it there specifically.)
I haven't tried it before but I'm almost certain it's possible to do with QMK or ZMK firmwares.
As for the lack of pins generally, the easiest thing to do would be to use a microcontroller with more pins, but that may bring more challenges when designing the pcb depending on the availability of good component footprints.
The most commonly used footprint is for the pro-micro though, but you'd end up needing to cut 4 rows/columns off of the board to fit within its pin constraints, though I do think there is a modification for pro-micros that can give you two more pins, which could technically work if you cut off the rightmost column and the function row.
If you're willing to get rid of just the rightmost row you would be able to use something like the nice!nano since it has 21 gpio pins. It would become optionally wireless in that case as well.
If you didn't want to cut down the board at all, could also go with something like an Elite Pi, which has a similar footprint to the pro-micro except with an extra 5 pins along the bottom edge, as it has the same footprint as the elite-c.
Quite a few options, and I'm not sure if you have a preference for wired vs. wireless or parts availability where you are, so those would likely influence what you decide to go with.
I prefer wired personally. As for product availability, I live in France, so it depends on what is easily available in my country.
Since you're in EU you have quite a few options for vendors. Here is a good list.
I looked through most of these vendors before and it's unlikely that you'll find everything you need to build a fully custom keyboard from a single vendor, but with 2 or more you should be able to source all the pieces you need.
Some vendors that have a decent selection:
Another option of you don't mind the potentially long shipping time is to buy all the components from Aliexpress. They will likely have an expansive selection and lower price compared with EU retailers, but you may or may not end up paying tax, and the shipping time will be longer on everything.
I managed to figure out an ugly way of getting the keyboard matrix down to 20 pins, but a much better option to using a pro-micro would be to go with an Elite-Pi or Helios Microcontroller Since it has 23 GPIO pins, and there won't be a hacky workaround like with the pro-micro.
One thing I forgot to mention is key switch preference, the two main types are MX (high profile) and Choc (low profile). MX switches are both easier to find and have much larger variety of both switches and keycaps. Choc is nice because it has a lower profile similar to laptop keyboards, but the selection of switches and keycaps are much more limited. There are other low profile switch types like Choc mini (PG1232), Choc V2(PG1353), and Notebook X(PG1425) switches, but they're even harder to source than the Choc V1(PG1350).