1 files changed, 142 insertions, 72 deletions

diff --git a/docs/feature_advanced_keycodes.md b/docs/feature_advanced_keycodes.md
index f93b8033a..8c0a22fc6 100644
--- a/docs/feature_advanced_keycodes.md
+++ b/docs/feature_advanced_keycodes.md
@@ -2,7 +2,7 @@
 
 Your keymap can include keycodes that are more advanced than normal, for example keys that switch layers or send modifiers when held, but send regular keycodes when tapped. This page documents the functions that are available to you.
 
-### Assigning Custom Names
+## Assigning Custom Names
 
 People often define custom names using `#define`. For example:
 
@@ -13,18 +13,21 @@ People often define custom names using `#define`. For example:
 
 This will allow you to use `FN_CAPS` and `ALT_TAB` in your `KEYMAP()`, keeping it more readable.
 
-### Limits of These Aliases
+## Caveats
 
-Currently, the keycodes able to used with these functions are limited to the [Basic Keycodes](keycodes_basic.md), meaning you can't use keycodes like `KC_TILD`, or anything greater than 0xFF. For a full list of the keycodes able to be used see [Basic Keycodes](keycodes_basic.md).
+Currently, `LT()` and `MT()` are limited to the [Basic Keycode set](keycodes_basic.md), meaning you can't use keycodes like `LCTL()`, `KC_TILD`, or anything greater than `0xFF`. Modifiers specified as part of a Layer Tap or Mod Tap's keycode will be ignored.
+
+Additionally, if at least one right-handed modifier is specified in a Mod Tap or Layer Tap, it will cause all modifiers specified to become right-handed, so it is not possible to mix and match the two.
 
 # Switching and Toggling Layers
 
-These functions allow you to activate layers in various ways. Note that layers are not generally independent layouts -- multiple layers can be activated at once, and it's typical for layers to use `KC_TRNS` to allow keypresses to pass through to lower layers. For a detailed explanation of layers, see [Keymap Overview](keymap.md#keymap-and-layers)
+These functions allow you to activate layers in various ways. Note that layers are not generally independent layouts -- multiple layers can be activated at once, and it's typical for layers to use `KC_TRNS` to allow keypresses to pass through to lower layers. For a detailed explanation of layers, see [Keymap Overview](keymap.md#keymap-and-layers) When using momentary layer switching with MO(), LM(), TT(), or LT(), make sure to leave the key on the above layers transparent or it may not work as intended.
 
 * `DF(layer)` - switches the default layer. The default layer is the always-active base layer that other layers stack on top of. See below for more about the default layer. This might be used to switch from QWERTY to Dvorak layout. (Note that this is a temporary switch that only persists until the keyboard loses power. To modify the default layer in a persistent way requires deeper customization, such as calling the `set_single_persistent_default_layer` function inside of [process_record_user](custom_quantum_functions.md#programming-the-behavior-of-any-keycode).)
 * `MO(layer)` - momentarily activates *layer*. As soon as you let go of the key, the layer is deactivated. 
 * `LM(layer, mod)` - Momentarily activates *layer* (like `MO`), but with modifier(s) *mod* active. Only supports layers 0-15 and the left modifiers.
-* `LT(layer, kc)` - momentarily activates *layer* when held, and sends *kc* when tapped.
+* `LT(layer, kc)` - momentarily activates *layer* when held, and sends *kc* when tapped. Only supports layers 0-15.
+* `OSL(layer)` - momentarily activates *layer* until the next key is pressed. See [One Shot Keys](#one-shot-keys) for details and additional functionality.
 * `TG(layer)` - toggles *layer*, activating it if it's inactive and vice versa
 * `TO(layer)` - activates *layer* and de-activates all other layers (except your default layer). This function is special, because instead of just adding/removing one layer to your active layer stack, it will completely replace your current active layers, uniquely allowing you to replace higher layers with a lower one. This is activated on keydown (as soon as the key is pressed).
 * `TT(layer)` - Layer Tap-Toggle. If you hold the key down, *layer* is activated, and then is de-activated when you let go (like `MO`). If you repeatedly tap it, the layer will be toggled on or off (like `TG`). It needs 5 taps by default, but you can change this by defining `TAPPING_TOGGLE` -- for example, `#define TAPPING_TOGGLE 2` to toggle on just two taps.
@@ -33,7 +36,7 @@ These functions allow you to activate layers in various ways. Note that layers a
 
 Care must be taken when switching layers, it's possible to lock yourself into a layer with no way to deactivate that layer (without unplugging your keyboard.) We've created some guidelines to help users avoid the most common problems.
 
-### Beginners
+## Beginners
 
 If you are just getting started with QMK you will want to keep everything simple. Follow these guidelines when setting up your layers:
 
@@ -41,11 +44,11 @@ If you are just getting started with QMK you will want to keep everything simple
 * Arrange your layers in a "tree" layout, with layer 0 as the root. Do not try to enter the same layer from more than one other layer.
 * In a layer's keymap, only reference higher-numbered layers. Because layers are processed from the highest-numbered (topmost) active layer down, modifying the state of lower layers can be tricky and error-prone.
 
-### Intermediate Users
+## Intermediate Users
 
 Sometimes you need more than one base layer. For example, if you want to switch between QWERTY and Dvorak, switch between layouts for different countries, or switch your layout for different videogames. Your base layers should always be the lowest numbered layers. When you have multiple base layers you should always treat them as mutually exclusive. When one base layer is on the others are off.
 
-### Advanced Users
+## Advanced Users
 
 Once you have a good feel for how layers work and what you can do, you can get more creative. The rules listed in the beginner section will help you be successful by avoiding some of the tricker details but they can be constraining, especially for ultra-compact keyboard users. Understanding how layers work will allow you to use them in more advanced ways.
 
@@ -55,57 +58,80 @@ Sometimes, you might want to switch between layers in a macro or as part of a ta
 
 # Modifier Keys
 
-These functions allow you to combine a mod with a keycode. When pressed the keydown for the mod will be sent first, and then *kc* will be sent. When released the keyup for *kc* will be sent and then the mod will be sent.
-
-* `LSFT(kc)` or `S(kc)` - applies left Shift to *kc* (keycode)
-* `RSFT(kc)` - applies right Shift to *kc*
-* `LCTL(kc)` - applies left Control to *kc*
-* `RCTL(kc)` - applies right Control to *kc*
-* `LALT(kc)` - applies left Alt to *kc*
-* `RALT(kc)` - applies right Alt to *kc*
-* `LGUI(kc)` - applies left GUI (command/win) to *kc*
-* `RGUI(kc)` - applies right GUI (command/win) to *kc*
-* `HYPR(kc)` - applies Hyper (all modifiers) to *kc*
-* `MEH(kc)`  - applies Meh (all modifiers except Win/Cmd) to *kc*
-* `LCAG(kc)` - applies CtrlAltGui to *kc*
-
-You can also chain these, like this:
-
-    LALT(LCTL(KC_DEL)) -- this makes a key that sends Alt, Control, and Delete in a single keypress.
-
-# Mod Tap
+These allow you to combine a modifier with a keycode. When pressed, the keydown event for the modifier, then `kc` will be sent. On release, the keyup event for `kc`, then the modifier will be sent.
+
+|Key       |Aliases               |Description                                         |
+|----------|----------------------|----------------------------------------------------|
+|`LCTL(kc)`|                      |Hold Left Control and press `kc`                    |
+|`LSFT(kc)`|`S(kc)`               |Hold Left Shift and press `kc`                      |
+|`LALT(kc)`|                      |Hold Left Alt and press `kc`                        |
+|`LGUI(kc)`|`LCMD(kc)`, `LWIN(kc)`|Hold Left GUI and press `kc`                        |
+|`RCTL(kc)`|                      |Hold Right Control and press `kc`                   |
+|`RSFT(kc)`|                      |Hold Right Shift and press `kc`                     |
+|`RALT(kc)`|`ALGR(kc)`            |Hold Right Alt and press `kc`                       |
+|`RGUI(kc)`|`RCMD(kc)`, `LWIN(kc)`|Hold Right GUI and press `kc`                       |
+|`HYPR(kc)`|                      |Hold Left Control, Shift, Alt and GUI and press `kc`|
+|`MEH(kc)` |                      |Hold Left Control, Shift and Alt and press `kc`     |
+|`LCAG(kc)`|                      |Hold Left Control, Alt and GUI and press `kc`       |
+|`SGUI(kc)`|`SCMD(kc)`, `SWIN(kc)`|Hold Left Shift and GUI and press `kc`              |
+|`LCA(kc)` |                      |Hold Left Control and Alt and press `kc`            |
+
+You can also chain them, for example `LCTL(LALT(KC_DEL))` makes a key that sends Control+Alt+Delete with a single keypress.
+
+# Mod-Tap
+
+The Mod-Tap key `MT(mod, kc)` acts like a modifier when held, and a regular keycode when tapped. In other words, you can have a key that sends Escape when you tap it, but functions as a Control or Shift key when you hold it down.
+
+The modifiers this keycode and `OSM()` accept are prefixed with `MOD_`, not `KC_`:
+
+|Modifier  |Description                             |
+|----------|----------------------------------------|
+|`MOD_LCTL`|Left Control                            |
+|`MOD_LSFT`|Left Shift                              |
+|`MOD_LALT`|Left Alt                                |
+|`MOD_LGUI`|Left GUI (Windows/Command/Meta key)     |
+|`MOD_RCTL`|Right Control                           |
+|`MOD_RSFT`|Right Shift                             |
+|`MOD_RALT`|Right Alt (AltGr)                       |
+|`MOD_RGUI`|Right GUI (Windows/Command/Meta key)    |
+|`MOD_HYPR`|Hyper (Left Control, Shift, Alt and GUI)|
+|`MOD_MEH` |Meh (Left Control, Shift, and Alt)      |
+
+You can combine these by ORing them together like so:
 
-`MT(mod, kc)` - is *mod* (modifier key - MOD_LCTL, MOD_LSFT) when held, and *kc* when tapped. In other words, you can have a key that sends Esc (or the letter O or whatever) when you tap it, but works as a Control key or a Shift key when you hold it down.
+```c
+MT(MOD_LCTL | MOD_LSFT, KC_ESC)
+```
 
-These are the values you can use for the `mod` in `MT()` and `OSM()`:
+This key would activate Left Control and Left Shift when held, and send Escape when tapped.
 
-  * MOD_LCTL
-  * MOD_LSFT
-  * MOD_LALT
-  * MOD_LGUI
-  * MOD_RCTL
-  * MOD_RSFT
-  * MOD_RALT
-  * MOD_RGUI
-  * MOD_HYPR
-  * MOD_MEH
+For convenience, QMK includes some Mod-Tap shortcuts to make common combinations more compact in your keymap:
 
-These can also be combined like `MOD_LCTL | MOD_LSFT` e.g. `MT(MOD_LCTL | MOD_LSFT, KC_ESC)` which would activate Control and Shift when held, and send Escape when tapped.
+|Key         |Aliases                                |Description                                            |
+|------------|---------------------------------------|-------------------------------------------------------|
+|`LCTL_T(kc)`|`CTL_T(kc)`                            |Left Control when held, `kc` when tapped               |
+|`RCTL_T(kc)`|                                       |Right Control when held, `kc` when tapped              |
+|`LSFT_T(kc)`|`SFT_T(kc)`                            |Left Shift when held, `kc` when tapped                 |
+|`RSFT_T(kc)`|                                       |Right Shift when held, `kc` when tapped                |
+|`LALT_T(kc)`|`ALT_T(kc)`                            |Left Alt when held, `kc` when tapped                   |
+|`RALT_T(kc)`|`ALGR_T(kc)`                           |Right Alt when held, `kc` when tapped                  |
+|`LGUI_T(kc)`|`LCMD_T(kc)`, `RWIN_T(kc)`, `GUI_T(kc)`|Left GUI when held, `kc` when tapped                   |
+|`RGUI_T(kc)`|`RCMD_T(kc)`, `RWIN_T(kc)`             |Right GUI when held, `kc` when tapped                  |
+|`C_S_T(kc)` |                                       |Left Control and Shift when held, `kc` when tapped     |
+|`MEH_T(kc)` |                                       |Left Control, Shift and Alt when held, `kc` when tapped|
+|`LCAG_T(kc)`|                                       |Left Control, Alt and GUI when held, `kc` when tapped  |
+|`RCAG_T(kc)`|                                       |Right Control, Alt and GUI when held, `kc` when tapped |
+|`ALL_T(kc)` |                                       |Left Control, Shift, Alt and GUI when held, `kc` when tapped - more info [here](http://brettterpstra.com/2012/12/08/a-useful-caps-lock-key/)|
+|`SGUI_T(kc)`|`SCMD_T(kc)`, `SWIN_T(kc)`             |Left Shift and GUI when held, `kc` when tapped         |
+|`LCA_T(kc)` |                                       |Left Control and Alt when held, `kc` when tapped       |
 
-We've added shortcuts to make common modifier/tap (mod-tap) mappings more compact:
+## Caveats
 
-  * `CTL_T(kc)` - is LCTL when held and *kc* when tapped
-  * `SFT_T(kc)` - is LSFT when held and *kc* when tapped
-  * `ALT_T(kc)` - is LALT when held and *kc* when tapped
-  * `ALGR_T(kc)` - is AltGr when held and *kc* when tapped
-  * `GUI_T(kc)` - is LGUI when held and *kc* when tapped
-  * `ALL_T(kc)` - is Hyper (all mods) when held and *kc* when tapped. To read more about what you can do with a Hyper key, see [this blog post by Brett Terpstra](http://brettterpstra.com/2012/12/08/a-useful-caps-lock-key/)
-  * `LCAG_T(kc)` - is CtrlAltGui when held and *kc* when tapped
-  * `MEH_T(kc)` - is like Hyper, but not as cool -- does not include the Cmd/Win key, so just sends Alt+Ctrl+Shift.
+Unfortunately, these keycodes cannot be used in Mod-Taps or Layer-Taps, since any modifiers specified in the keycode are ignored.
 
-?> Due to the way that keycodes are structured, any modifiers specified as part of `kc`, such as `LCTL()` or `KC_LPRN`, will only activate when held instead of tapped.
+Additionally, you may run into issues when using Remote Desktop Connection on Windows. Because these codes send shift very fast, Remote Desktop may miss the codes.
 
-?> Additionally, if there is at least one right-handed modifier, any other modifiers in a chain of functions will turn into their right-handed equivalents, so it is not possible to "mix and match" the two.
+To fix this, open Remote Desktop Connection, click on "Show Options", open the the "Local Resources" tab. In the keyboard section, change the drop down to "On this Computer". This will fix the issue, and allow the characters to work correctly.
 
 # One Shot Keys
 
@@ -115,6 +141,8 @@ For example, if you define a key as `OSM(MOD_LSFT)`, you can type a capital A ch
 
 One shot keys also work as normal modifiers. If you hold down a one shot key and type other keys, your one shot will be released immediately after you let go of the key.
 
+Additionally, hitting keys five times in a short period will lock that key. This applies for both One Shot Modifiers and One Shot Layers, and is controlled by the `ONESHOT_TAP_TOGGLE` define.
+
 You can control the behavior of one shot keys by defining these in `config.h`:
 
 ```c
@@ -125,42 +153,78 @@ You can control the behavior of one shot keys by defining these in `config.h`:
 * `OSM(mod)` - Momentarily hold down *mod*. You must use the `MOD_*` keycodes as shown in [Mod Tap](#mod-tap), not the `KC_*` codes.
 * `OSL(layer)` - momentary switch to *layer*.
 
-Sometimes, you want to activate a one-shot layer as part of a macro or tap dance routine. To do this, you need to call `set_oneshot_layer(LAYER, ONESHOT_START)` on key down, and `set_oneshot_layer(ONESHOT_PRESSED)` on key up. If you want to cancel the oneshot, call `reset_oneshot_layer()`. For more complicated actions, take a look at the oneshot implementation in [`process_record`](https://github.com/qmk/qmk_firmware/blob/master/tmk_core/common/action.c#L429).
+Sometimes, you want to activate a one-shot key as part of a macro or tap dance routine.  
+
+For one shot layers, you need to call `set_oneshot_layer(LAYER, ONESHOT_START)` on key down, and `set_oneshot_layer(ONESHOT_PRESSED)` on key up. If you want to cancel the oneshot, call `reset_oneshot_layer()`.
 
-If you're having issues with OSM translating over Remote Desktop Connection, this can be fixed by opening the settings, going to the "Local Resources" tap, and in the keyboard section, change the drop down to "On this Computer".  This will fix the issue and allow OSM to function properly over Remote Desktop.
+For one shot mods, you need to call `set_oneshot_mods(MOD)` to set it, or `clear_oneshot_mods()` to cancel it.
 
-# Permissive Hold
+!> If you're having issues with OSM translating over Remote Desktop Connection, this can be fixed by opening the settings, going to the "Local Resources" tap, and in the keyboard section, change the drop down to "On this Computer".  This will fix the issue and allow OSM to function properly over Remote Desktop.
+
+# Tap-Hold Configuration Options
+
+While Tap-Hold options are fantastic, they are not without their issues.  We have tried to configure them with reasonal defaults, but that may still cause issues for some people. 
+
+These options let you modify the behavior of the Tap-Hold keys.
+
+## Permissive Hold
 
 As of [PR#1359](https://github.com/qmk/qmk_firmware/pull/1359/), there is a new `config.h` option:
 
-```
+```c
 #define PERMISSIVE_HOLD
 ```
 
-This makes it easier for fast typists to use dual-function keys. Without this, if you let go of a held key inside the tapping term, it won't register.
+This makes tap and hold keys (like Mod Tap) work better for fast typist, or for high `TAPPING_TERM` settings. 
 
-Example: (Tapping Term = 200ms)
+If you press a Mod Tap key, tap another key (press and release) and then release the Mod Tap key, all within the tapping term, it will output the "tapping" function for both keys.
 
-- SHFT_T(KC_A) Down
-- KC_X Down
-- KC_X Up
-- SHFT_T(KC_A) Up
+For Instance:
 
-With defaults, if above is typed within tapping term, this will emit `ax`. With permissive hold, if above is typed within tapping term, this will emit `X` (so, Shift+X).
+- `SHFT_T(KC_A)` Down
+- `KC_X` Down
+- `KC_X` Up
+- `SHFT_T(KC_A)` Up
 
-# Mod tap interrupt
+Normally, if you do all this within the `TAPPING_TERM` (default: 200ms) this will be registered as `ax` by the firmware and host system. With permissive hold enabled, this modifies how this is handled by considering the Mod Tap keys as a Mod if another key is tapped, and would registered as `X` (`SHIFT`+`x`). 
 
-When a dual role key used for a modifier is quickly followed by another keys, it is interpreted as held even before the tapping term elapsed.  This is a problem if a key is used for example inside a rolling combo because the second key will be pressed before the first key is released.
+?> If you have `Ignore Mod Tap Interrupt` enabled, as well, this will modify how both work. The regular key has the modifier added if the first key is released first or if both keys are held longer than the `TAPPING_TERM`.
 
-For example, when trying to type the rolling combo "zx" and z being configured to send Ctrl when hold, z rapidly followed by x actually sends Ctrl-x. That's bad.
+## Ignore Mod Tap Interrupt
 
-You can disable this behavior by defining `IGNORE_MOD_TAP_INTERRUPT` in `config.h`.
+To enable this setting, add this to your `config.h`:
 
-Note that this only concerns modifiers and not layer switching keys.
+```c
+#define IGNORE_MOD_TAP_INTERRUPT
+```
+
+Similar to Permissive Hold, this alters how the firmware processes input for fast typist. If you press a Mod Tap key, press another key, release the Mod Tap key, and then release the normal key, it would normally output the "tapping" function for both keys. This may not be desirable for rolling combo keys. 
+
+Setting `Ignore Mod Tap Interrupt` requires  holding both keys for the `TAPPING_TERM` to trigger the hold function (the mod).
+
+For Instance:
+
+- `SHFT_T(KC_A)` Down
+- `KC_X` Down
+- `SHFT_T(KC_A)` Up
+- `KC_X` Up
+
+Normally, this would send `X` (`SHIFT`+`x`). With `Ignore Mod Tap Interrupt` enabled, holding both keys are required for the `TAPPING_TERM` to register the hold action. A quick tap will output `ax` in this case, while a hold on both will still output `X`  (`SHIFT`+`x`).
+
+
+?> __Note__: This only concerns modifiers and not layer switching keys.
+
+?> If you have `Permissive Hold` enabled, as well, this will modify how both work. The regular key has the modifier added if the first key is released first or if both keys are held longer than the `TAPPING_TERM`.
 
-# Hold after tap
+## Tapping Force Hold
 
-When the user holds a key after tap, this repeats the tapped key rather to hold a modifier key.  This allows to use auto repeat for the tapped key.  If you prefer to hold a modifier instead, define `TAPPING_FORCE_HOLD` in `config.h`.
+To enable `tapping force hold`, add the following to your `config.h`: 
+
+```c
+#define TAPPING_FORCE_HOLD
+```
+
+When the user holds a key after tap, this repeats the tapped key rather to hold a modifier key.  This allows to use auto repeat for the tapped key.  
 
 Example:
 
@@ -176,8 +240,14 @@ With `TAPPING_FORCE_HOLD`, the second press will be interpreted as a Shift, allo
 
 !> `TAPPING_FORCE_HOLD` will break anything that uses tapping toggles (Such as the `TT` layer keycode, and the One Shot Tapping Toggle).
 
-# Retro Tapping
+## Retro Tapping
+
+To enable `retro tapping`, add the following to your `config.h`: 
+
+```c
+#define RETRO_TAPPING
+```
 
-When you hold a dual function key, and haven't pressed anything when you release the key, normally nothing happens.  However, if you enable this, if you release the key without pressing another key, it will send the original key, even if it is outside of the tapping term. 
+Holding and releasing a dual function key without pressing another key will result in nothing happening. With retro tapping enabled, releasing the key without pressing another will send the original keycode even if it is outside the tapping term.
 
-For instance, if you're using `LT(2, KC_SPACE)`, if you hold the key, don't hit anything else and then release it, normally, nothing happens. But with `RETRO_TAPPING` defined in your `config.h`, it will send `KC_SPACE`. 
+For instance, holding and releasing `LT(2, KC_SPACE)` without hitting another key will result in nothing happening. With this enabled, it will send `KC_SPACE` instead.