Desync's Keymap

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Overview

• Base layer is a magic modded graphite/gallium layout. (Alternative base layers available.)
• Many common symbols and punctuation are accessible through combos.
• Home row mods selectively available on most layers.
• Chordal Hold enabled with opposite hand triggers for home row mod and Repeat/Magic layer-tap safety.
• Rollback feature for magic outputs and macros.
• Case lock for easy snake_case, kebab-case, dot.case, and camelCase usage.
• Mouse emulation accessible on pinky key combo; movement keys in same position as arrow keys on navigation layer, scrolling underneath in vim arrow layout.
• Media control on Utility layer.
• Control key overrides for easier left-hand only use; overrides disabled on home row mods.
• Locking numpad and Steno (GeminiPR) layers accessible through combos.

Features

Dynamic Keys

Repeat and Magic are dynamic keys that return different outputs depending on the previous key.

As the name suggests, the Repeat key repeats the last key pressed; while the Magic key swaps the first and second rows, along with various keys on the index columns (with some exceptions, listed below). This eliminates many SFBs and double-taps, turning them into alternations and rolls.

The most common use-case for the swapping-rows behaviour is for the vowel block on the right side, turning the OE, EO, IU, and UI SFBs into rolls and alternations; as well as eliminating various index finger SFBs on both sides (i.e., in the words T[YP]E, [SC]IENCE, [HYP]HEN, etc.).

Letters that are not commonly repeated (i.e. I, U, A) are overridden and instead return common n-grams. (Some letters uncommonly repeated in prose are still common in LaTeX commands and have not been overridden.)

Magic Key

Left hand keys:

Prev	Z	L	D	C	B	N	R	T	S	G	Q	X	M	W	V
Magic	N	R	T	S	ECAUSE⎵	'T	L	MENT	C	S	U	C	ENT	S	S

Right hand overrides:

Prev	J	O	U	Y	H	E	I	A
Magic	ECT	E	I	P	ERE	O	ON	ND⎵

(Other right hand keys are repeated.)

Other:

Non-alpha	⎵	,	.	'
OSM Shift	OSM Shift	⎵AND⎵	⎵+OSM Shift	VE⎵

Repeat Key

Right hand keys:

Prev	J	F	O	U	Y	H	E	I	A	K	P
Repeat	UST	Y	O	I	P	Y	E	U	ND⎵	Y	H

Left hand overrides:

Prev	X	V	W
Repeat	ES	ER	ITH

(Other left hand keys are repeated.)

Other:

Magic*	Non-alpha	⎵	,	.	'
⎵	THE	THE	⎵BUT⎵	COM	RE⎵

*Unless the previous magic output already ended with a space, in which case the repeat key will default to the Non-alpha state; or if the previous magic output was a basic repeat (F, K, and P), in which case the repeat key will treat the magic key as an ordinary alpha key.

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Details

Only the keys listed above are tracked (including those from combos). Pressing any other key resets the key to the default Non-alpha state (i.e. OSM Shift/THE).

a 1 [Rep] produces a 1 the.

Modifiers are not tracked (but the dynamic keys may be modified):

[Shift] a [Release shift] [Magic] produces A a;

a [Shift] [Magic] [Release shift] produces a A.

Any keys pressed while the control modifier is active are not tracked. This does not reset key tracking:

a [CTRL] b [Release CTRL] [Magic] produces a ^b a.

Backspace reverts the tracked key to the previous key:

a b c [Rep] produces a b c c (Rep returns c);

a b c [BSPC] [Rep] produces a b b (Rep returns previous tracked key b).

Note that this feature only tracks two keys into the past.

After a short duration (default 1000ms) of no keyboard input, both dynamic keys will reset to the Non-alpha state.

In QWERTY and Basic modes, both dynamic keys are overridden to only have repeat functionality.

Rollbacks

For longer dynamic key outputs (e.g. W -> WITH), there is a short window (default 500ms) in which Backspace will delete ("rollback") the entire magic output (i.e. WITH -> W rather than WITH -> WIT).

Pressing any other key will instantly close this window.

This feature is also reused to rollback various macro outputs in a single keypress.

Note

You can hook into this feature with the process_key_tracking and rollback_last_key functions.

Case Lock

Tapping the Case Lock key will prime the feature, capturing the next key pressed to be used as a separator. Then, the Space key will emit the captured separator instead of a space.

By default, the only keys that can be captured are _ (snake_case), - (kebab-case), . (dot.case), and LSFT (camelCase).

Note

This can be customised in the process_case_lock and process_case_capture functions.

Capturing the Case Lock will instead activate Caps Lock.

Tapping the Space key twice while case lock is active will delete the separator, output a space, and disable case lock.

While case lock is active, Ctrl+Bspc will instead delete to the previous separator rather than deleting the entire word.

OLEDs

(128x64 OLEDs)

Right:

• Default layer and layer stack display;
• Menu key swaps layer stack to layout display;
• Clock — time is set manually using keys on utility layer and doesn't require software on host (persists through sleep events);
• Custom locking key, modifier, and mute state indicators.

Left:

• Cycles between text and logo with cyberpunk glich aesthetic animation (based on this code);
• Logo displays WPM and current session time.

Key on utility layer available to change both OLEDs to static images.

Combos

(Press Esc, ;, and # to access Touhou layer and to see funky Cirno fumo on right OLED.)

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• Common punctuation is accessible from combos on or near home row;
• Mouse emulation layer accessible on pinky key combos to allow mouse control without moving from home row.
• Uncommon locking layers (numpad/steno) also accessible from large combos;
• New combo presses DOT, SPC, then sets a one shot shift.

Pressing Spc plus a key on the left hand top row will output the function keys F1 to F5 for left-hand-only usage. (Not shown on image due to reduce clutter.)

⚠️ Experimental Features

Various additional experimental features that have not yet been incorporated into the main keymap may be found on various branches. Current features in development:

Steno-lite

This feature adds a selection of combos that output common words or word fragments.

These combos can be triggered by pressing Magic or Repeat, along with the specified combo keys listed below. Most of these combos agree with magic/repeat outputs.

Magic:

Combo	B	T	TH	TI	S	M	W	WH
Output	because⎵	tment⎵	that⎵	this⎵	some⎵	ment⎵	with⎵	what⎵

Combo	WI	J	F	Y	H	E	I	A
Output	which⎵	ject⎵	from⎵	you've⎵	here⎵	every⎵	ion⎵	about⎵

Repeat:

Combo	B	T	TH	TI	S	M	W	WH
Output	but⎵	the	that	this	some	ment	with	what

Combo	WI	J	F	Y	H	E	I	A
Output	which	just	from	you're⎵	have	every	ing⎵	and

Arrow Layout Toggle

This feature allows you to swap the arrow keys on the Edit layer between an inverted-T and line (vim-like) layout.

Pressing the pinky key (line left) while in inverted-T swaps to line mode, and pressing the upper middle key (inverted-T up) while in line mode swaps to inverted-T.

Quadrant-based mouse keys

Based on qmk/qmk_firmware#24760, this feature uses the digitiser support to move the mouse pointer to absolute positions rather than relative ones as per the built-in mouse keys feature as follows: the screen is divided up into a quadrants; pressing one of the directional keys snaps the pointer to the centre of that quadrant, and then the grid is rescaled to the quadrant; then, movement can be repeated within the quadrant.

The original thread uses 8 directional keys and shrinks the grid uniformly in every direction, but I found the diagonal keys difficult to use. This version instead only allows four directional keys, and tracks the vertical and horizontal scales separately; pressing up will snap the pointer upwards and reduce the vertical scale, but leave the horizontal scale unchanged, and vice versa; moving along the same axis twice will reduce the scale in both directions. I find this version more intuitive to use as it more closely matches the standard inverted-T key layout, where you press (or alternate between) multiple direction keys to move diagonally.

Due to the digitiser feature mapping outputs to the whole virtual desktop, it does not interact well with multiple monitors, as the minimum step size becomes much too large; furthermore, the digitiser feature can also attempt to place the cursor offscreen if the virtual desktop is not a rectangle, which is especially prominent if the monitors have different orientations or unusual positionings. However, on single monitors, this feature has the potential to be much faster than using standard mouse keys.

I currently keep a copy of this fork on my offside half, so I can swap to it when not at my desktop by plugging in the other side of the split. In the future, I may add the ability to toggle between the two modes in the main keymap.

Layers

Base

Base layer alphas is a slightly modified graphite layout, with home row mods, and magic/repeat keys on middle thumb keys.

I find it difficult to press upper row keys with my pinkies and end up alt fingering them with my ring fingers, which introduces some SFBs (BL, BR) with the default Graphite layout. So, J and B have been moved off the outer top row; B has also been placed next to C to make the common B_C string not a skipgram. Also, I don't like E on the ring finger, so HEIA is used over HAEI.

Note

The keymap internally uses a QWERTY layer (specifically, the _BASIC layer) for combo tracking, so this Base layer can be modified easily without needing any changes to combo code.

Warning

However, per-key mod-tap settings and Chordal Hold config will still need to be handled separately if home row mods are changed.

Comma, Dot, Scln, Colon, Dash, and Exlm are compressed together or omitted, as they accessible from combos near or on the home row. (These combos are accessible on almost every layer.) Hash is also included on base layer as I use it as a LaTeX snippet trigger/(reverse) leader key.

A copy of Tab is placed on the right hand to reduce left hand contortions. The two Tab keys also function as LShift and RShift when held. The shift modifiers are applied eagerly on keydown to improve interaction with pointing devices; these eager shift modifiers do not overwrite home row mods, so you can still shift-tab with one hand.

The LCTL key also sets a weak one shot ctrl modifier for the Backspace key only to allow for faster usage while typing. The one shot modifier lingers for 500ms and is removed on any other keypress (without being applied).

Data

Number grid with 1, 2, and 3 on right hand home row, along with common numerical separators on left hand home row, sharing similar layout to Symbol and Program layers.

The bracket macros {-}, (-), and [-] send the listed brackets, then tap Left, placing the cursor between the two brackets. These macros also interoperate with the rollback feature.

The @ symbol is also available on this layer as many email handles end with numbers, and also because I use it as a leader key for LaTeX commands; and ~ is available for git commands.

Activating both Data and Program layers will also activate the Edit layer on top to allow for quick navigation during numerical input. This is implemented via the tri-layer feature, so the layer keys may be released in any order without issue.

Edit

Navigation/editing keys on left hand and paired delimiters and common symbol combinations on right hand. I prefer the navigation cluster on the left hand to allow usage with the mouse.

Many common strings are inward rolls on right hand, e.g.; [], (), {}, ^{}, _{}, !(), ?(); right hand also duplicated on Symbol and Program layers.

The two directional Select macros select in the indicated directions from the current cursor position. Pressing/holding the keys will extend the selection one word at a time; activating the opposite macro will retract the selection instead.

The Select macro selects the current word; pressing it again will cut (Ctrl+X) the selection. Pressing it after one of the two other directional Select macros will also immediately cut the selection.

After cutting with Select, the Enter key on this layer will act as paste (Ctrl+V), resetting after the first use, or if the Edit layer is disabled.

The bottow row of the Control Overlay can also be activated with home row mods on this layer.

The right thumb keys also have additional layering actions:

• Activating both Edit and Program layers will also activate the Edit Overlay, containing macros useful for editing.
• Activating both Edit and Symbol layers will replace the right hand with a copy of the Data layer, and also hold the LCTL or LSFT modifier for various keys on the left hand. These are both implemented via the tri-layer feature, so the layer keys may be released in any order without issue.

Symbol

Symbol layout optimised for (La)TeX editing with many common strings as inward rolls on left hand, e.g.; <-, <=, ->, >=, |->, <-, ~>, |>, :=, :-, &=, etc. (Intended to be used with snippet extensions.) Brackets on right hand as above.

Program

Program layer optimised for programming (mostly C and Python). Inward rolls include:

• comparison operators: !=, >=, <= on home row;
• arithmetic assignment operators: ^=, +=, -=, *=, /= above and below home row. Bitwise operator symbols are grouped on the inner index column. Holding shift while pressing & or | will send the respective symbol twice, i.e. as logical operators.

Brackets on right hand as above.

Utility

Utility layer containing media control, RGB controls, OLED controls, function keys, and debug functions. Layer is accessible using either outer thumb key (XOR).

The Mute thumb keys only activate on the hand opposite to the one holding the layer key to avoid accidental activations. The Volume Up/Down keys are macros that rapidly and repeatedly send the volume control keycodes for smooth volume control; holding shift sends the keycodes only once for finer control.

Base swaps default layer to QWERTY layout; Basic swaps default layer to QWERTY layout with home row mods and Space layer-tap disabled (Data layer is still accessible by holding down the OSL key on base layer).

Clock keys set the OLED clock. OLED Static disables animations and changes OLEDs to static images. OLED Menu toggles between layer stack view and layout display on right OLED.

Alt Tab key holds LAlt and taps Tab on first press; taps Tab on subsequent presses; LAlt is released when layer key is released.

Tap the Reboot key to reboot keyboard; hold for one second to enter bootloader.

Mouse

Mouse emulation accessible on pinky key combo to allow mouse movement without moving from home row. A mirrored left hand combo is also available, intended to be used with the layer lock feature.

Cursor/scroll speed may be overridden with right thumb keys for higher speed or finer control.

Overlay Layers

Control Overlay

Control key overrides with QWERTY-esque layout for easier left-hand only use. (I usually don't remember which letter does what command, only which key position, particularly for graphical and editing software)

Overrides activate only from left hand control key on a base layer; home row mods are unaffected, so intentional letter controls can be used in two-hand usage.

Holding LCTL on any layer (including non-base layers) covers the left hand bottom row with: Redo, Undo, Cut, Copy, and Paste shortcuts (i.e. overlays only the bottom row of this layer).

Edit Overlay

Activating the Program layer while on the Edit layer will activate the Edit Overlay layer on top (of the Edit layer). This is implemented via the tri-layer feature, so the layer keys may be released in any order without issue.

The right hand is replaced with macros useful for editing:

• The (directional) Delete macros function similarly to the selection macros, except deleting the selection.

• The Line macro adds new lines above/below the current line.

• The Join macro joins current line to following line with space between; does not add space if shifted.

• The three bracket macros enclose the current word with the listed brackets. (Compare with the bracket macros on the Data layer.) These macros also interoperate with the rollback feature.

While this layer is active, the LCTL modifier is held for the Delete and Page keys, and LSFT is held for the Home and End keys.

Alt Base Layer

QWERTY

Accessible with Base key on Utility layer, or Basic to also disable home row mods and Space layer-tap (for games).

Warning

Modifying the _BASIC layer will also require changing mod-tap and combo code.

Some notes on implementation

CS_XXXX Keycodes

I've had problems in the past with rolling built-in shifted keycodes. For instance, &= is a very common inward roll (in LaTeX), but the shift from the ampersand would often persist through to the equals symbol, outputting &+ instead. (And similar problems with other rolls.)

The CS_XXXX keycodes explicitly reset shift modifiers before sending the intended keycode, fixing this issue. They also rename the keycodes to their ISO counterparts. These keycodes also can't be shifted manually: this is intended -- every symbol should be accessible on some layer without needing the shift key at all -- shift should only be needed for normal letters.

This has probably been fixed in the years since I first encountered this issue, but there's little reason to swap back to ordinary keycodes as; the keycode renaming is convenient for maintenance; the shift-disabling behaviour is desired; and it works as-is.

I also don't use key overrides for this purpose, because they override all matching instances of inputs when active, and sometimes I do want to manually send strange combinations of modifiers and keycodes.

By the way, CS originally stood for Custom Symbol, but I've ended up using the prefix for any custom key I implement, mostly because it's easy to search/regex for.

Layers

You may notice that this keymap has a lot of layers defined. In practice however, you'll only really be using 6 or so layers: the Base layer, Edit, Data, Symbol, Program, and Utility. The other 10 are either persistent locking layers (different base layers/numpad/steno, etc.), or are there to make the internal layer switching implementation simpler (including "overlay" layers).

Because layers are arranged in a stack that is scanned top-down, there isn't an easy way to move from a higher layer to a lower layer momentarily. I've done some implementations of this before, but they are often error-prone to work with, difficult to maintain and troubleshoot, and often don't interact well with other features. Alternatively, I could make every key on every layer that needs this behaviour a custom key that performs different actions depending on the currently held keys, but this is even worse for maintenance, even if it is slightly more memory efficient. To save myself the trouble, I just stack extra layers on top wherever I need them.

Repeat Key

I am aware that there is a built-in QMK implementation of the repeat/magic key. However, my original implementation predates the repeat key being merged into the main branch. Furthermore, I've customised my dynamic keys so much at this point that it's easier to keep using my own implementation as I keep all of the functions exposed and can hook into it anywhere. In particular, the rollback feature and various dynamic macros do this extensively.

Other

If there's anything else in the keymap that looks inefficient or badly implemented, that's probably because it's very old and I didn't want to look into it too deeply when refactoring, and/or I didn't put much thought into it when I was first making it.

If you find a way to clean up some of my code or fix some bugs, that's lovely, and a PR would be appreciated. However, this is my personal keymap, so I will not be accepting any PRs that change functionality meaningfully; please make a fork if you would like to experiment on your own copy.

Building

1. Set up a local installation of QMK.

2. Clone this repository into qmk_firmware\keyboards\crkbd\keymaps.

   git clone https://github.com/DesyncTheThird/corne-keymap qmk_firmware\keyboards\crkbd\keymaps\desync

3. Build the keymap from the QMK CLI with:

   qmk compile -c -kb crkbd -km desync

   Note, however:

Caution

Unmodified, this keymap will not fit on most AVR MCUs (and in fact may fail to compile in some cases due to overflowing 8-bit integers).

For reference, my compiled uf2 file is 218kB (accurate as of commit 972be81), though you should be able to save a significant amount of space by removing various OLED animations, deleting unused layers (along with the associated OLED layout PROGMEM), and disabling additional RGB animations (the CS_RGBN key will need to be updated in this case).

See here for more ways to save space. (Most space-saving rules.mk and config.h options have already been enabled; only modify those files if you have disabled additional features in keymap.c.)

Tip

I recommend using an RP2040 or another ARM MCU with more space. (Plus, they're generally cheaper and faster than AVR pro-micros.)

4. To use a drop-in replacement controller, additionally use a converter flag: -e CONVERT_TO=<converter>.

   For instance, I use a (non-Sparkfun) RP2040 controller, so my full build command is:

   qmk compile -c -kb crkbd -km desync -e CONVERT_TO=rp2040_ce

5. OS Setup:

   • Regional layout: English (United Kingdom)