zmk/docs/docs/behaviors/key-press.md

title	sidebar_label
Key Press Behaviors	Key Press

Summary

The most basic of behaviors, is the ability to send certain keycode presses and releases in response to activating a certain key.

The categories of supported codes are:

• Keyboard & Keypad
• Editing
• Media
• Applications
• Input Assist
• Power

Please visit the codes section for a comprehensive list.

For advanced users, user-defined HID usages are also supported but must be encoded, please see dt-bindings/zmk/keys.h for further insight.

Keycode Defines

To make it easier to encode the HID keycode numeric values, most keymaps include the dt-bindings/zmk/keys.h header provided by ZMK near the top:

#include <dt-bindings/zmk/keys.h>

Doing so makes a set of defines such as A, N1, etc. available for use with these behaviors

Improperly defined keymap - dtlib.DTError: <board>.dts.pre.tmp:<line number>

When compiling firmware from a keymap, it may be common to encounter an error in the form of adtlib.DTError: <board>.dts.pre.tmp:<line number>. For instructions to resolve such an error, click here

Key Press

The "key press" behavior sends standard keycodes on press/release.

Behavior Binding

• Reference: &kp
• Parameter: The keycode usage ID from the usage page, e.g. 4 or A

Example:

&kp A