There are 3 standard keyboard layouts in use around the world- ANSI, ISO, and JIS. North America primarily uses ANSI, Europe and Africa primarily use ISO, and Japan uses JIS. Regions not mentioned typically use either ANSI or ISO. The keycodes corresponding to these layouts are shown here:
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QMK has two features, Bootmagic and Command, which allow you to change the behavior of your keyboard on the fly. This includes, but is not limited to, swapping Ctrl/Caps, disabling Gui, swapping Alt/Gui, swapping Backspace/Backslash, disabling all keys, and other behavioral modifications.
As a quick fix try holding down `Space`+`Backspace` while you plug in your keyboard. This will reset the stored settings on your keyboard, returning those keys to normal operation. If that doesn't work look here:
The key found on most modern keyboards that is located between `KC_RGUI` and `KC_RCTL` is actually called `KC_APP`. This is because when that key was invented there was already a key named `MENU` in the relevant standards, so MS chose to call that the `APP` key.
Use keycode for Print Screen(`KC_PSCREEN` or `KC_PSCR`) instead of `KC_SYSREQ`. Key combination of 'Alt + Print Screen' is recognized as 'System request'.
Modifier keys or layers can be stuck unless layer switching is configured properly.
For Modifier keys and layer actions you have to place `KC_TRANS` on same position of destination layer to unregister the modifier key or return to previous layer on release event.
This feature is for *mechanical lock switch* like [this Alps one](http://deskthority.net/wiki/Alps_SKCL_Lock). You can enable it by adding this to your `config.h`:
Old vintage mechanical keyboards occasionally have lock switches but modern ones don't have. ***You don't need this feature in most case and just use keycodes `KC_CAPS`, `KC_NLCK` and `KC_SLCK`.***
I think you can send Apple Fn key using Apple venter specific Page 0xff01 and usage 0x0003. But you have to change HID Report Descriptor for this, of course.
Japanese JIS keyboard specific keys like `無変換(Muhenkan)`, `変換(Henkan)`, `ひらがな(hiragana)` are not recognized on OSX. You can use **Seil** to enable those keys, try following options.
Karabiner - Keymapping tool on Mac OSX - ignores inputs from RN-42 module by default. You have to enable this option to make Karabiner working with your keyboard.
This turns right modifier keys into arrow keys when the keys are tapped while still modifiers when the keys are hold. In TMK the dual-role function is dubbed **TAP**.
Not sure what keycode Eject is on genuine Apple keyboard actually. HHKB uses `F20` for Eject key(`Fn+f`) on Mac mode but this is not same as Apple Eject keycode probably.