Keymap glossary
Key terms that show up in custom split-keyboard keymaps. Each term has an anchor so other pages can link straight in.
- Layer
- An overlay that switches the key arrangement. Symbol / number / function layers are typically activated only while a designated key is held.
- mo (Momentary Layer)
- Activate a layer only while the key is held (ZMK &mo N, QMK MO(N)). Releases back to the previous layer. Commonly assigned to a thumb key.
- mt (Mod-Tap)
- A single key that sends a character on tap and a modifier on hold (ZMK &mt MOD KEY). Lets you reach modifiers without leaving the home row.
- lt (Layer-Tap)
- Character on tap, layer hold on hold (ZMK < N KEY). Hold Space for a symbol layer is the canonical example.
- kp (Key Press)
- A plain keypress. ZMK &kp A or QMK KC_A — the most basic binding.
- trans / none
- trans falls through to the binding from a lower layer; none does nothing. Both help avoid accidental keypresses in higher layers.
- Combo
- Pressing multiple keys (nearly) simultaneously to fire a different key — e.g. F + D = Escape. Adds functionality without adding keys.
- Home-row mods
- Assign Shift / Ctrl / Alt / GUI to home-row keys via mt. Powerful but tap-term tuning is essential to avoid misfires.
- Romaji (Hepburn / Kunrei)
- Typing Japanese with ASCII letters. Hepburn uses chi / shi / tsu, Kunrei uses ti / si / tu. daken accepts both as correct.
- Physical layout
- Coordinates describing where each key sits on the board. The i-th binding in a layer maps to the i-th key position.