scrcpy/doc/keyboard.md

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Keyboard

Several keyboard input modes are available:

  • --keyboard=sdk (default)
  • --keyboard=uhid (or -K): simulates a physical HID keyboard using the UHID kernel module on the device
  • --keyboard=aoa: simulates a physical HID keyboard using the AOAv2 protocol
  • --keyboard=disabled

By default, sdk is used, but if you use scrcpy regularly, it is recommended to use uhid and configure the keyboard layout once and for all.

SDK keyboard

In this mode (--keyboard=sdk, or if the parameter is omitted), keyboard input events are injected at the Android API level. It works everywhere, but it is limited to ASCII and some other characters.

Note that on some devices, an additional option must be enabled in developer options for this keyboard mode to work. See prerequisites.

Additional parameters (specific to --keyboard=sdk) described below allow to customize the behavior.

Text injection preference

Two kinds of events are generated when typing text:

  • key events, signaling that a key is pressed or released;
  • text events, signaling that a text has been entered.

By default, numbers and "special characters" are inserted using text events, but letters are injected using key events, so that the keyboard behaves as expected in games (typically for WASD keys).

But this may cause issues. If you encounter such a problem, you can inject letters as text (or just switch to UHID):

scrcpy --prefer-text

(but this will break keyboard behavior in games)

On the contrary, you could force to always inject raw key events:

scrcpy --raw-key-events

Key repeat

By default, holding a key down generates repeated key events. Ths can cause performance problems in some games, where these events are useless anyway.

To avoid forwarding repeated key events:

scrcpy --no-key-repeat

Physical keyboard simulation

Two modes allow to simulate a physical HID keyboard on the device.

To work properly, it is necessary to configure (once and for all) the keyboard layout on the device to match that of the computer.

The configuration page can be opened in one of the following ways:

  • from the scrcpy window (when uhid or aoa is used), by pressing MOD+k (see shortcuts)
  • from the device, in Settings → System → Languages and input → Physical devices
  • from a terminal on the computer, by executing adb shell am start -a android.settings.HARD_KEYBOARD_SETTINGS

From this configuration page, it is also possible to enable or disable on-screen keyboard.

UHID

This mode simulates a physical HID keyboard using the UHID kernel module on the device.

To enable UHID keyboard, use:

scrcpy --keyboard=uhid
scrcpy -K  # short version

Once the keyboard layout is configured (see above), it is the best mode for using the keyboard while mirroring:

  • it works for all characters and IME (contrary to --keyboard=sdk)
  • the on-screen keyboard can be disabled (contrary to --keyboard=sdk)
  • it works over TCP/IP (wirelessly) (contrary to --keyboard=aoa)
  • there are no issues on Windows (contrary to --keyboard=aoa)

One drawback is that it may not work on old Android versions due to permission errors.

AOA

This mode simulates a physical HID keyboard using the AOAv2 protocol.

To enable AOA keyboard, use:

scrcpy --keyboard=aoa

Contrary to the other modes, it works at the USB level directly (so it only works over USB).

It does not use the scrcpy server, and does not require adb (USB debugging). Therefore, it is possible to control the device (but not mirror) even with USB debugging disabled (see OTG).

Note: On Windows, it may only work in OTG mode, not while mirroring (it is not possible to open a USB device if it is already open by another process like the adb daemon).