See [doc/keycode.txt](https://github.com/tmk/tmk_keyboard/blob/master/doc/keycode.txt).
See [doc/keycode.txt](https://github.com/tmk/tmk_core/blob/master/doc/keycode.txt).
Keycodes are actually defined in [common/keycode.h](https://github.com/tmk/tmk_keyboard/blob/master/tmk_core/common/keycode.h).
Keycodes are actually defined in [common/keycode.h](https://github.com/tmk/tmk_core/blob/master/common/keycode.h).
## Sysrq key
## 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'.
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.
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.
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.