Keymap framework - how to define your keymap
============================================
-***NOTE: This is not final version, may be inconsistent with source code and changed occasionally for a while.***
+***NOTE: This is updated for QMK but this is still work in progress. This may still be inconsistent with the source code.***
+
+QMK is based on TMK. Understanding the essential changes made should help you understand variable names etc.
+
+## TMK vs. QMK
+
+| Firmware |TMK |QMK |
+|-------------------------------------------------|-----------------------|-------------------------|
+| Maintainer |hasu |Jack Humbert et al. |
+| Build path customization | `TMK_DIR = ...` | `include .../Makefile` |
+| `keymaps` data | 3D array of `uint8_t` holding **keycode** | 3D array of `uint16_t` holding **action code** |
+| `fn_actions` data | 1D array of `uint16_t` holding **action code** | 3D array of `uint16_t` holding **action code** |
+
+Since QMK is based on TMK and uses major portion of TMK code as is, understanding the essential changes made should help you understand the code.
## 0. Keymap and layers
-**Keymap** is comprised of multiple layers of key layout, you can define **32 layers** at most.
-**Layer** is an array of **keycodes** to define **actions** for each physical keys.
-respective layers can be validated simultaneously. Layers are indexed with 0 to 31 and higher layer has precedence.
+In QMK, **`const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS]`** holds multiple **layers** of keymap information in **16 bit** data holding the **action code**. You can define **32 layers** at most.
- Keymap: 32 Layers Layer: Keycode matrix
+For trivial key definitions, the higher 8 bits of the **action code** are all 0 and the lower 8 bits holds the USB HID usage code generated by the key as **keycode**.
+
+Respective layers can be validated simultaneously. Layers are indexed with 0 to 31 and higher layer has precedence.
+
+ Keymap: 32 Layers Layer: action code matrix
----------------- ---------------------
- stack of layers array_of_keycode[row][column]
+ stack of layers array_of_action_code[row][column]
____________ precedence _______________________
/ / | high / ESC / F1 / F2 / F3 ....
31 /___________// | /-----/-----/-----/-----
0 /___________/ V low 0 `--------------------------
+Sometimes, the action code stored in keymap may be referred as keycode in some documents due to the TMK history.
+
+### 0.1 Keymap layer status
+Keymap layer has its state in two 32 bit parameters:
-### 0.1 Keymap status
-Keymap has its state in two parameters:
-**`default_layer`** indicates a base keymap layer(0-31) which is always valid and to be referred, **`keymap_stat`** is 16bit variable which has current on/off status of layers on its each bit.
+* **`default_layer_state`** indicates a base keymap layer(0-31) which is always valid and to be referred.
+* **`layer_state`** () has current on/off status of the layer on its each bit.
+Keymap has its state in two parameter**`default_layer`** indicates a base keymap layer(0-31) which is always valid and to be referred, **`keymap_stat`** is 16bit variable which has current on/off status of layers on its each bit.
Keymap layer '0' is usually `default_layer` and which is the only valid layer and other layers is initially off after boot up firmware, though, you can configured them in `config.h`.
To change `default_layer` will be useful when you switch key layout completely, say you want Colmak instead of Qwerty.
### 0.2 Layer Precedence and Transparency
Note that ***higher layer has higher priority on stack of layers***, namely firmware falls down from top layer to bottom to look up keycode. Once it spots keycode other than **`KC_TRNS`**(transparent) on a layer it stops searching and lower layers aren't referred.
-You can place `KC_TRNS` on overlay layer changes just part of layout to fall back on lower or base layer.
-Key with `KC_TRANS` doesn't has its own keycode and refers to lower valid layers for keycode, instead.
+You can place `KC_TRANS` on overlay layer changes just part of layout to fall back on lower or base layer.
+Key with `KC_TRANS` (`KC_TRNS` and `_______` are the alias) doesn't has its own keycode and refers to lower valid layers for keycode, instead.
See example below.
### 0.3 Keymap Example
-Keymap is **`keymaps[]`** C array in fact and you can define layers in it with **`KEYMAP()`** C macro and keycodes. To use complex actions you need to define `Fn` keycode in **`fn_actions[]`** array.
+Keymap in this QMK is **`static const uint16_t PROGMEM keymaps[]`** C array in fact and you can define layers in it with **`KEYMAP()`** C macro and keycodes. To use complex actions you need to define `Fn` keycode in **`fn_actions[]`** array. It holds the 16 bit quantum keycode (action code).
+
+> Please note that keymap in the TMK, which QMK was forked from, is **`static const uint8_t PROGMEM keymaps[]`** C array which holds the 8 bit keycode (~USB HID usage code).
This is a keymap example for [HHKB](http://en.wikipedia.org/wiki/Happy_Hacking_Keyboard) keyboard.
-This example has three layers, 'Qwerty' as base layer, 'Cursor' and 'Mousekey'.
+This example has three layers, 'QWERTY' as base layer, 'FN' and 'MOUSE'.
+
In this example,
- `Fn0` is a **momentary layer switching** key, you can use keys on Cursor layer while holding the key.
+ `MO(layer)` is a **momentary layer switching** key.
- `Fn1` is a momentary layer switching key with tapping feature, you can get semicolon **';'** with taping the key and switch layers while holding the key. The word **'tap'** or **'tapping'** mean to press and release a key quickly.
+You can find other keymap definitions in file `keymap.c` located on project directories.
+```
+/*
+ * dbroqua HHKB Layout
+ */
+#include "hhkb.h"
+
+#define BASE 0
+#define FN 1
+#define MOUSE 2
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+ /* BASE Level: Default Layer
+ * ,-----------------------------------------------------------------------------------------.
+ * | Esc | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | - | = | \ | ` |
+ * |-----------------------------------------------------------------------------------------+
+ * | Tab | Q | W | E | R | T | Y | U | I | O | P | [ | ] | Bksp |
+ * |-----------------------------------------------------------------------------------------+
+ * | Ctrl | A | S | D | F | G | H | J | K | L | ; | ' | Enter |
+ * |-----------------------------------------------------------------------------------------+
+ * | Shift | Z | X | C | V | B | N | M | , | . | / | Shift | fn |
+ * +-----------------------------------------------------------------------------------------+
+ * | Gui | Alt | Space | AltGr |Mouse|
+ * `----------------------------------------------------------------´
+ */
+ [BASE] = KEYMAP(
+ KC_ESC, KC_1, KC_2, KC_3, KC_4, KC_5, KC_6, KC_7, KC_8, KC_9, KC_0, KC_MINS, KC_EQL, KC_BSLS, KC_GRV, \
+ KC_TAB, KC_Q, KC_W, KC_E, KC_R, KC_T, KC_Y, KC_U, KC_I, KC_O, KC_P, KC_LBRC, KC_RBRC, KC_BSPC, \
+ KC_LCTL, KC_A, KC_S, KC_D, KC_F, KC_G, KC_H, KC_J, KC_K, KC_L, KC_SCLN, KC_QUOT, KC_ENT, \
+ KC_LSFT, KC_Z, KC_X, KC_C, KC_V, KC_B, KC_N, KC_M, KC_COMM, KC_DOT, KC_SLSH, KC_RSFT, MO(FN), \
+ KC_LGUI, KC_LALT, /* */ KC_SPC, KC_RALT, MO(MOUSE)
+ ),
+
+ /* FN Layer
+ * ,-----------------------------------------------------------------------------------------.
+ * | Pwr | F1 | F2 | F3 | F4 | F5 | F6 | F7 | F8 | F9 | F0 | F11 | F12 | Ins | Del|
+ * |-----------------------------------------------------------------------------------------+
+ * | Caps | | | | | | | |PrtSc| Slck| Paus| Up | | |
+ * |-----------------------------------------------------------------------------------------+
+ * | | Vol-| Vol+| Mute| | | * | / | Home| PgUp| Left |Right| |
+ * |-----------------------------------------------------------------------------------------+
+ * | | Prev| Play| Next| | | + | - | End |PgDwn| Down| | |
+ * +-----------------------------------------------------------------------------------------+
+ * | | | | Stop | |
+ * `----------------------------------------------------------------´
+ */
+ [FN] = KEYMAP(
+ KC_PWR, KC_F1, KC_F2, KC_F3, KC_F4, KC_F5, KC_F6, KC_F7, KC_F8, KC_F9, KC_F10, KC_F11, KC_F12, KC_INS, KC_DEL, \
+ KC_CAPS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_PSCR, KC_SLCK, KC_PAUS, KC_UP, KC_TRNS, KC_TRNS, \
+ KC_TRNS, KC_VOLD, KC_VOLU, KC_MUTE, KC_TRNS, KC_TRNS, KC_PAST, KC_PSLS, KC_HOME, KC_PGUP, KC_LEFT, KC_RGHT, KC_TRNS, \
+ KC_TRNS, KC_MPRV, KC_MPLY, KC_MNXT, KC_TRNS, KC_TRNS, KC_PPLS, KC_PMNS, KC_END, KC_PGDN, KC_DOWN, KC_TRNS, KC_TRNS, \
+ KC_TRNS, KC_TRNS, KC_TRNS, KC_MSTP, KC_TRNS
+ ),
+
+ /* MOUSE Layer
+ * ,-----------------------------------------------------------------------------------------.
+ * | | | | | | | | | | | | | | | |
+ * |-----------------------------------------------------------------------------------------+
+ * | | | WUp | | | | | | | | Btn1| Up | Btn2| |
+ * |-----------------------------------------------------------------------------------------+
+ * | | WLt | WDn | WRt | | | | | | | Left |Right| |
+ * |-----------------------------------------------------------------------------------------+
+ * | | | | | | | | | | Btn3| Down| | |
+ * +-----------------------------------------------------------------------------------------+
+ * | | | | | |
+ * `----------------------------------------------------------------´
+ */
+ [MOUSE] = KEYMAP(
+ KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, \
+ KC_TRNS, KC_TRNS, KC_WH_U, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_BTN1, KC_MS_U, KC_BTN2, KC_TRNS, \
+ KC_TRNS, KC_WH_L, KC_WH_D, KC_WH_R, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_MS_L, KC_MS_R, KC_TRNS, \
+ KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_BTN3, KC_MS_D, KC_TRNS, KC_TRNS, \
+ KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS, KC_TRNS
+ )
+};
- `Fn2` is a **toggle layer switch** key, you can stay switched layer after releasing the key unlike momentary switching.
+const uint16_t PROGMEM fn_actions[] = {
-You can find other keymap definitions in file `keymap.c` located on project directories.
+};
- static const uint8_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
- /* 0: Qwerty
- * ,-----------------------------------------------------------.
- * |Esc| 1| 2| 3| 4| 5| 6| 7| 8| 9| 0| -| =| \| `|
- * |-----------------------------------------------------------|
- * |Tab | Q| W| E| R| T| Y| U| I| O| P| [| ]|Backs|
- * |-----------------------------------------------------------|
- * |Contro| A| S| D| F| G| H| J| K| L|Fn1| '|Enter |
- * |-----------------------------------------------------------|
- * |Shift | Z| X| C| V| B| N| M| ,| .| /|Shift |Fn0|
- * `-----------------------------------------------------------'
- * |Gui|Alt |Space |Alt |Fn2|
- * `-------------------------------------------'
- */
- KEYMAP(ESC, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, MINS,EQL, BSLS,GRV, \
- TAB, Q, W, E, R, T, Y, U, I, O, P, LBRC,RBRC,BSPC, \
- LCTL,A, S, D, F, G, H, J, K, L, FN1, QUOT,ENT, \
- LSFT,Z, X, C, V, B, N, M, COMM,DOT, SLSH,RSFT,FN0, \
- LGUI,LALT, SPC, RALT,FN2),
- /* 1: Cursor(HHKB mode)
- * ,-----------------------------------------------------------.
- * |Pwr| F1| F2| F3| F4| F5| F6| F7| F8| F9|F10|F11|F12|Ins|Del|
- * |-----------------------------------------------------------|
- * |Caps | | | | | | | |Psc|Slk|Pus|Up | |Backs|
- * |-----------------------------------------------------------|
- * |Contro|VoD|VoU|Mut| | | *| /|Hom|PgU|Lef|Rig|Enter |
- * |-----------------------------------------------------------|
- * |Shift | | | | | | +| -|End|PgD|Dow|Shift | |
- * `-----------------------------------------------------------'
- * |Gui |Alt |Space |Alt |Gui|
- * `--------------------------------------------'
- */
- KEYMAP(PWR, F1, F2, F3, F4, F5, F6, F7, F8, F9, F10, F11, F12, INS, DEL, \
- CAPS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,PSCR,SLCK,PAUS,UP, TRNS,BSPC, \
- LCTL,VOLD,VOLU,MUTE,TRNS,TRNS,PAST,PSLS,HOME,PGUP,LEFT,RGHT,ENT, \
- LSFT,TRNS,TRNS,TRNS,TRNS,TRNS,PPLS,PMNS,END, PGDN,DOWN,RSFT,TRNS, \
- LGUI,LALT, SPC, RALT,RGUI),
- /* 2: Mousekey
- * ,-----------------------------------------------------------.
- * |Esc| F1| F2| F3| F4| F5| F6| F7| F8| F9|F10|F11|F12|Ins|Del|
- * |-----------------------------------------------------------|
- * |Tab | | | | | |MwL|MwD|MwU|MwR| | | |Backs|
- * |-----------------------------------------------------------|
- * |Contro| | | | | |McL|McD|McU|McR| | |Return |
- * |-----------------------------------------------------------|
- * |Shift | | | | |Mb3|Mb2|Mb1|Mb4|Mb5| |Shift | |
- * `-----------------------------------------------------------'
- * |Gui |Alt |Mb1 |Alt | |
- * `--------------------------------------------'
- * Mc: Mouse Cursor / Mb: Mouse Button / Mw: Mouse Wheel
- */
- KEYMAP(ESC, F1, F2, F3, F4, F5, F6, F7, F8, F9, F10, F11, F12, INS, DEL, \
- TAB, TRNS,TRNS,TRNS,TRNS,TRNS,WH_L,WH_D,WH_U,WH_R,TRNS,TRNS,TRNS,BSPC, \
- LCTL,TRNS,ACL0,ACL1,ACL2,TRNS,MS_L,MS_D,MS_U,MS_R,TRNS,QUOT,ENT, \
- LSFT,TRNS,TRNS,TRNS,TRNS,BTN3,BTN2,BTN1,BTN4,BTN5,SLSH,RSFT,TRNS, \
- LGUI,LALT, BTN1, RALT,TRNS),
- };
+const macro_t *action_get_macro(keyrecord_t *record, uint8_t id, uint8_t opt)
+{
+ // MACRODOWN only works in this function
+ switch(id) {
+ case 0:
+ if (record->event.pressed) {
+ register_code(KC_RSFT);
+ } else {
+ unregister_code(KC_RSFT);
+ }
+ break;
+ }
+ return MACRO_NONE;
+};
+```
- static const uint16_t PROGMEM fn_actions[] = {
- ACTION_LAYER_MOMENTARY(1), // FN0
- ACTION_LAYER_TAP_KEY(2, KC_SCLN), // FN1
- ACTION_LAYER_TOGGLE(2), // FN2
- };
+## 1. Keycode
+See [`tmk_core/common/keycode.h`](../tmk_core/common/keycode.h) or keycode table below for the detail. Keycode is internal **8bit code** to indicate action performed on key in keymap. Keycodes are based on [HID Usage Keyboard/Keypad Page(0x07)](http://www.usb.org/developers/hidpage/Hut1_12v2.pdf) plus special codes in the `0xA5-DF` range.
+
+Keycode has `KC_` prefixed symbol respectively. Most of keycodes like `KC_A` have simple action registers key to host on press and unregister on release, while some of other keycodes has some special actions like `Fn` keys, Media control keys, System control keys and Mousekeys.
+keymaps[]
+In `KEYMAP()` macro, TMK recommends you to keep prefix part `KC_` of keycode to keep keymap compact. For example, just use `A` instead you place `KC_A` in `KEYMAP()`. But this doesn't apply for QMK.
-## 1. Keycode
-See [`common/keycode.h`](../common/keycode.h) or keycode table below for the detail. Keycode is internal **8bit code** to indicate action performed on key in keymap. Keycode has `KC_` prefixed symbol respectively. Most of keycodes like `KC_A` have simple action registers key to host on press and unregister on release, while some of other keycodes has some special actions like `Fn` keys, Media control keys, System control keys and Mousekeys.
+The `KEYMAP()` macro defines correspondence between the physical key location to the electrical key connection.
- ***In `KEYMAP()` macro you should omit prefix part `KC_` of keycode to keep keymap compact.*** For example, just use `A` instead you place `KC_A` in `KEYMAP()`. Some keycodes has 4-letter **short name** in addition to descriptive name, you'll prefer short one in `KEYMAP()`.
+Some keycodes has 7-letter **short name** such as `KC_COMM` in addition to descriptive name `KC_COMMA`, you'll prefer short one in `KEYMAP()`.
### 1.0 Other key
- `KC_NO` for no action
- `KC_WSCH`, `KC_WHOM`, `KC_WBAK`, `KC_WFWD`, `KC_WSTP`, `KC_WREF`, `KC_WFAV` for web browser operation
### 1.5 Fn key
-`KC_FNnn` are keycodes for `Fn` key which not given any actions at the beginning unlike most of keycodes has its own inborn action. To use these keycodes in `KEYMAP()` you need to assign action you want at first. Action of `Fn` key is defined in `fn_actions[]` and its index of the array is identical with number part of `KC_FNnn`. Thus `KC_FN0` keycode indicates the action defined in first element of the array. ***32 `Fn` keys can be defined at most.***
+You don't need to use this functionality under QMK since this is a backward compatibility functionality. Unlike TMK, you can write action code itself directly in **`static const uint16_t PROGMEM keymaps[]`** C array using `MO(layer)`, etc.
+
+`KC_FNnn` are keycodes for `Fn` key which not given any actions at the beginning unlike most of keycodes has its own inborn action. To use these keycodes in `KEYMAP()` you need to assign action you want at first. Action of `Fn` key is defined in `fn_actions[]` and its index of the array is identical with number part of `KC_FNnn`. Thus `KC_FN0` keycode indicates the action defined in first element of the array. ***Only 32 `Fn` keys can be defined at most.***
+
### 1.6 Keycode Table
See keycode table in [`doc/keycode.txt`](./keycode.txt) for description of keycodes.
## 5. Legacy Keymap
-This was used in prior version and still works due to legacy support code in `common/keymap.c`. Legacy keymap doesn't support many of features that new keymap offers. ***It is not recommended to use Legacy Keymap for new project.***
-
-To enable Legacy Keymap support define this macro in `config.h`.
-
- #define USE_LEGACY_KEYMAP
+In QMK, `tmk_core/common/keymap.c` is missing and its replacement `quantum/keymap_common.c` lacks Legacy Keymap support.
Legacy Keymap uses two arrays `fn_layer[]` and `fn_keycode[]` to define Fn key. The index of arrays corresponds with postfix number of `Fn` key. Array `fn_layer[]` indicates destination layer to switch and `fn_keycode[]` has keycodes to send when tapping `Fn` key.
-In following setting example, `Fn0`, `Fn1` and `Fn2` switch layer to 1, 2 and 2 respectively. `Fn2` registers `Space` key when tapping while `Fn0` and `Fn1` doesn't send any key.
+In the following legacy keymap setting example, `Fn0`, `Fn1` and `Fn2` switch layer to 1, 2 and 2 respectively. `Fn2` registers `Space` key when tapping while `Fn0` and `Fn1` doesn't send any key.
static const uint8_t PROGMEM fn_layer[] = {
1, // Fn0
KC_SPC, // Fn2
};
+Under QMK, these can be realized using action code ACTION_LAYER_TAP_KEY(1, KC_NO), ACTION_LAYER_TAP_KEY(2, KC_NO), and ACTION_LAYER_TAP_KEY(2, KC_SPC) in the `keymaps` directly.
## 6. Terminology
***TBD***
projects / qmk_firmware.git / commitdiff