qmk_firmware/FAQ-Keymap.md

READ FIRST

https://github.com/tmk/tmk_keyboard/blob/master/doc/keymap.md

How to get keycode

See doc/keycode.txt. Keycodes are actually defined in common/keycode.h.

Sysrq 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'.

See issue #168 and

• http://en.wikipedia.org/wiki/Magic_SysRq_key
• http://en.wikipedia.org/wiki/System_request

Power key doesn't work

Use KC_PWR instead of KC_POWER or vice versa.

• KC_PWR works with Windows and Linux, not with OSX.
• KC_POWER works with OSX and Linux, not with Windows.

http://geekhack.org/index.php?topic=14290.msg1327264#msg1327264

Oneshot modifier

Solves my personal 'the' problem. I often got 'the' or 'THe' wrongly instead of 'The'. Oneshot Shift mitgates this for me. https://github.com/tmk/tmk_keyboard/issues/67

Modifier/Layer stuck

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.

https://github.com/tmk/tmk_keyboard/blob/master/doc/keymap.md#31-momentary-switching http://geekhack.org/index.php?topic=57008.msg1492604#msg1492604

Mechanical Lock Switch Support

https://github.com/tmk/tmk_keyboard#mechanical-locking-support

This feature is for mechanical lock switch like this Alps one. http://deskthority.net/wiki/Alps_SKCL_Lock

Using enabling this feature and using keycodes LCAP, LNUM or LSCR in keymap you can use physical locking CapsLock, NumLock or ScrollLock keys as you expected.

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 CAPS, NLCK and SLCK.

Input special charactors other than ASCII like Cédille 'Ç'

NO UNIVERSAL METHOD TO INPUT THOSE WORKS OVER ALL SYSTEMS. You have to define MACRO in way specific to your OS or layout.

See this post for example MACRO code.

http://deskthority.net/workshop-f7/tmk-keyboard-firmware-collection-t4478-120.html#p195620

On Windows you can use AltGr key or Alt code.

• http://en.wikipedia.org/wiki/AltGr_key
• http://en.wikipedia.org/wiki/Alt_code

On Mac OS defines Option key combinations.

• http://en.wikipedia.org/wiki/Option_key#Alternative_keyboard_input

On Xorg you can use compose key, instead.

• http://en.wikipedia.org/wiki/Compose_key

And see this for Unicode input.

• http://en.wikipedia.org/wiki/Unicode_input

Apple keyboard Fn

Not supported.

Apple keyboard sends keycod for Fn unlike most of other keyboards. I think you can send Apple Fn key using Appleventer Page 0xff00 and usage 0x0003. You have to change HID Report Descriptor, of course.

https://opensource.apple.com/source/IOHIDFamily/IOHIDFamily-606.1.7/IOHIDFamily/AppleHIDUsageTables.h

Media control keys in Mac OSX

See PR #160.

The "Play/Pause"(KC_MPLY) works good on Apple OS. But "Next/Prev Track" buttons are unfunctional. Apple OS use "Fast Forwad"(F9 on Apple keyboard) & "Rewind"(F7 on Apple keyboard) instead.

Use KC_MFFD(KC_MEDIA_FAST_FORWARD) and KC_MRWD(KC_MEDIA_REWIND) instead of KC_ and KC_MNXT and KC_MPRV.

Keys supported in Mac OSX?

You can know which keycodes are supported in OSX from this source code.

usb_2_adb_keymap array maps Keyboard/Keypad Page usages to ADB scancodes(OSX internal keycodes).

https://opensource.apple.com/source/IOHIDFamily/IOHIDFamily-606.1.7/IOHIDFamily/Cosmo_USB2ADB.c

And IOHIDConsumer::dispatchConsumerEvent handles Consumer page usages.

https://opensource.apple.com/source/IOHIDFamily/IOHIDFamily-606.1.7/IOHIDFamily/IOHIDConsumer.cpp