Steno Keyboard

Project Logs

Collapse

Version Two
deʃhipu • 02/22/2021 at 23:10 • 0 comments

As you might have guessed from the previous log, I decided to try and make another stenotype. This time with a little bit more experience from my low-profile keyboard projects. Of course it's low-profile, and of course it runs CircuitPython.
I used blue Kailh Choc switches, because they are very light, with 25g springs. That is important, because you are usually pressing a lot of keys at once, and the forces add up quickly. The switches are linear, not clicky, but I think it's fine.
I used some keycaps I had left over from building other keyboards — mostly function keys and some random stuff like Print Screen or alternate Alt. I couldn't use keys with proper legends, because the letters repeat here, so I would need several sets. Instead I bought several sheets of stickers for "converting" your keyboard to a different layout. They look bad, but it works well enough for training.
Right now I programmed it as a keyboard to be used with Plover, but ultimately I want to make it work like real stenotypes, as a serial device. CircuitPython just recently had a se]cond USB CDC device added, so I can use that.
Soon...
deʃhipu • 11/25/2020 at 16:36 • 0 comments

It's Alive, ALIVE!

deʃhipu • 08/01/2017 at 15:44 • 0 comments

Having cleaned the switches overnight, in the morning I started to work on the wiring. I used a two-sided tape to glue a Pro Micro to the base, added a USB cable (I had to file the plug a little to make it fit inside the keyboard), and started to add the wires and diodes.

I decided to use 3 rows and 8 columns, with the two large keys in the same row as the vowels on the bottom. This lets me return the row status as a single byte and makes the scanning quite fast.

For software, I used the same TMK keyboard firmware as in #Alpen Clack, with just two changes, one to the key map:

static const uint8_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
  {
    {KC_W,    KC_E,    KC_R,    KC_U,    KC_I,   KC_O,   KC_P,    KC_LBRC},
    {KC_S,    KC_D,    KC_F,    KC_J,    KC_K,   KC_L,   KC_SCLN, KC_QUOT},
    {KC_Q,    KC_T,    KC_C,    KC_V,    KC_N,   KC_M,   KC_NO,   KC_NO},
  },
};

and one to the matrix functions:

/* Column pin configuration
 * col: 8
 * pin: PD0 PD1 PD2 PD3 PD4 PD7 PC6 PE6
 */
static void  init_cols(void) {
    // Input with pull-up(DDR:0, PORT:1)
    DDRD  &= ~0b10011111;
    PORTD |=  0b10011111;
    DDRC  &= ~0b01000000;
    PORTC |=  0b01000000;
    DDRE  &= ~0b01000000;
    PORTE |=  0b01000000;
}
static matrix_row_t read_cols(void) {
    return (PIND&(1<<0) ? 0:(1<<0)) |
           (PIND&(1<<1) ? 0:(1<<1)) |
           (PIND&(1<<2) ? 0:(1<<2)) |
           (PIND&(1<<3) ? 0:(1<<3)) |
           (PIND&(1<<4) ? 0:(1<<4)) |
           (PIND&(1<<7) ? 0:(1<<5)) |
           (PINC&(1<<6) ? 0:(1<<6)) |
           (PINE&(1<<6) ? 0:(1<<7));
}
/* Row pin configuration
 * row: 3
 * pin: PF7 PF6 PF5
 */
static void unselect_rows(void) {
    // Hi-Z(DDR:0, PORT:0) to unselect
    DDRF  &= ~0b11100000;
    PORTF &= ~0b11100000;
}
static void select_row(uint8_t row) {
    // Output low(DDR:1, PORT:0) to select
    switch (row) {
        case 0:
            DDRF  |= (1<<7);
            PORTF &= ~(1<<7);
            break;
        case 1:
            DDRF  |= (1<<6);
            PORTF &= ~(1<<6);
            break;
        case 2:
            DDRF  |= (1<<5);
            PORTF &= ~(1<<5);
            break;
    }
}

Unfortunately the Pro Micro doesn't break out any of its pin ports in whole, so I had to use multiple ports for the columns. I still have whole port B free, I might decide to add LEDs to the keys as a teaching help. For now let's keep things simple.

I don't have any CapsLock or NumLock keys, so the LEDs on the board are unused. I still placed it in such a place, that it is visible, just in case I might need them for something later.

Once I made all the connections and uploaded the firmware, I realized that 5 of the switches actually didn't survive the glue removal operation — they give no electrical connection. Fortunately I still had a bunch of switches left to replace them.

Now I'm going through the lessons at https://sites.google.com/site/ploverdoc/lesson-1-fingers-and-keys

Back on the Ring
deʃhipu • 08/01/2017 at 02:01 • 0 comments

I found this keyboard today in my drawer, and decided to try and revive it. The project got, um, paused indefinitely over a year ago, when I stupidly got superglue inside the key switches, and pretty much ruined them.
Today I decided to take a little bit of risk -- since the switches are broken anyways the way they are -- and applied a little bit of acetone to one of the keys. Lo and behold, it budged! A little bit of wiggling and scraping and removing the gunk from it, and it works almost as well as it used to. Great! Only 21 more to go!
Three hours later I pretty much have all the switches working (I had to replace one of them, but fortunately I still had some spares), and I am back to where the project was last time -- I have the rows of the keys soldered, and now I need to solder a diode to each key and then connect the columns, and connect everything to a Pro Micro.
Abort Mission
deʃhipu • 04/15/2016 at 12:58 • 5 comments

Last Monday I worked a little bit more on this keyboard. I decided to start on the wiring. I did the rows, and then I decided the keys are not sitting in their holes well enough. So I decided to do what I did with my previous two keyboards -- glue the switches in place.
Unfortunately, this time I used instant glue, and applied it when the keyboard was up-side-down, so that the glue got into the switches. Sure enough, they are all glued hard, and there is no force that could budge them now. I suppose I could try removing them, opening each and cleaning, but they would never again work as well as before, and I honestly don't have any stamina left to do it.
So I'm aborting this project, with a small possibility of reviving it if I get my hands on some spare switches again.
Backplate
deʃhipu • 04/06/2016 at 10:55 • 0 comments

OK, the power of procrastination is immense. I already made the backplate. Started by cutting a rectangle from a piece of sheet metal. Who needs laser cutters when you have a hacksaw?
Next, I taped the two plates together and drilled the holes, then did some filing and dremeling to make the metal plate smooth and to round its corners. The result:
I used nylon spacers to connect the two plates together, cutting off the excess pieces of the bolts.
Next up: wiring.
Keycaps
deʃhipu • 04/06/2016 at 08:45 • 0 comments

The blank keycaps I ordered finally arrived. I decided to use blanks, because this keyboard layout is really non-standard, and it would be difficult to get the right keys with the right letters on them, especially since some of the letters repeat. I might figure out some way of adding the letters on those keycaps later on, we will see.
The keycaps are low-profile, but the keyboard is still pretty high -- as is expected with a mechanical keyboard. Next I need to cut a bottom plate for it, but that's after the conference.
Designing a Keyboard
deʃhipu • 03/26/2016 at 19:53 • 0 comments
I've been through building a keyboard twice already, so this time I knew exactly what to do. First I went to http://www.keyboard-layout-editor.com/ and made a keyboard with the steno layout, which, for English at least, looks like this:
Then I clicked on the "raw data" tab, and copied the keyboard definition, which looks like this:
```
[{a:7,h:2},"S","T","P","H",{h:2},"<i class='fa fa-asterisk'></i>","F","P","L","T","D"],
[{x:1},"K","W","R",{x:1},"R","B","G","S","Z"],
[{x:2.5},"A","O","E","U"
```
Then I went to http://builder.swillkb.com/ and pasted that code in there. After selecting some options, it generated me an SVG file that looks like this:
I opened that in Libre Office (Inkscape has problem with exporting PDFs with very thin lines), changed the line width to 0.01mm, saved that as PDF and went to the nearby FabLab to have it laser-cut. I actually choose too weak laser power, so the cuts were not whole way through, and then I moved it, so I couldn't repeat the cutting, but nothing that can't be fixed with a bit of demeling. Final plate looks like this:
I still have some Gateron Brown switches left from my previous keyboard, so I will be using those. They just snap into those holes -- easy enough. Keycaps are a bigger problem -- as you can see, I will need several with the same letter, and also for different rows than normally. The keys on your keyboard usually have different height depending on which row they are.
So I went to http://pimpmykeyboard.com/ and ordered myself some blank keycaps. I also picked the low-profile ones, which are all the same height. This is actually the most expensive part of this project. Now I'm waiting for the keycaps to arrive.