IBM Model M - On So Many Alien Steroids

[broken-username]

Hopefully the title was catchy enough.

I'm anticipating my first Model M, having designed and built keyboards mostly around MX and Alps switches up to this point. Since nothing quite compares to buckling springs, I thought there was really only one way that the experience could be any better for me - the addition of my favorite QMK firmware with all the bells and whistles one could ask for, bringing an already excellent design into the modern era. Unsurprisingly, someone had this idea some time ago: https://github.com/qmk/qmk_firmware/tree/master/keyboards/converter/ibm_terminal
Adapted from the original TMK version

I'm currently thinking of using a Pro Micro internally and adding a speaker with a potentiometer and PAM8403 to use QMK's supported sounds at a non-eardrum-splitting volume. I'm well-versed enough in QMK that all the especially nice features (like macros, special modifiers, dual-role keys, layers, etc.) shouldn't pose a challenge.

But I also have potentially silly questions. The person whose source code I'm using as a base did their work on a terminal model, and the one I have coming has the common SDL-PS2 connection. Would I need to alter anything in software significantly to make it work? In other words, are there huge differences between the PS2 and terminal types that I need to know about? The connections look identical, but I'd hate to get to building it only to find out that wasn't so. I admit to being pretty uninformed about the Model M specifics and thought asking here would be the easiest way to get specific answers. If people who know far more than I do would chime in, that would be most appreciated.

[broken-username]

Well, I did it. Apparently not all scan code 3 values work with this particular keyboard, but I cheated a little and did some substitutions from scan code 2. It's not 1 to 1 one with that set, since there are some extended codes that I haven't created any code to handle yet. It's working well now, even so.

An internal build is a bit harder than I was expecting, so I'm being lazy at the moment and hooking it up externally just so I can say it works. Next will be some Colemak keycaps from Unicomp once I have some extra money.

[user 18]

Next will be some Colemak keycaps from Unicomp once I have some extra money.

Just in case you're unaware, all the 1u keys for the Model M are the same profile, so you can rearrange them without any worry about messing up the profiles. That way, I think the only new key you'd need for Colemak is the caps lock -> backspace.

[broken-username]

Just in case you're unaware, all the 1u keys for the Model M are the same profile, so you can rearrange them without any worry about messing up the profiles. That way, I think the only new key you'd need for Colemak is the caps lock -> backspace.

Correct, and thank you. I have two reasons for wanting new keycaps. One is the homing bumps (having them anywhere but the home row drives me nuts!), two is the fact that these keycaps are a little bit worn.

It also wouldn't hurt to have Hyper and Meta keycaps from Unicomp. That's closer to what the Control and Alt keys are actually doing now, plus it's a bit more like the Symbolics keyboards that I love.

A note for those that attempt this in the future: The numpad can be used for macro keys if desired, but be aware that they have a relationship with the arrow keys and the six keys immediately above them. By default, those keys will produce macros as well if you only change the numpad keys to macros. I realize it's kind of a "duh" upon reflection, but it wasn't immediately obvious to me.