.. zephyr:code-sample:: settings :name: Settings API :relevant-api: settings settings_rt settings_name_proc Load and save configuration values using the settings API. Overview ******** This is a simple application demonstrating use of the settings runtime configuration module. In this application some configuration values are loaded from persistent storage and exported to persistent storage using different settings method. The example shows how to implement module handlers, how to register them. Requirements ************ * A board with settings support, for instance: nrf52840dk_nrf52840 * Or qemu_x86 target Building and Running ******************** This sample can be found under :zephyr_file:`samples/subsys/settings` in the Zephyr tree. The sample can be build for several platforms, the following commands build the application for the qemu_x86. .. zephyr-app-commands:: :zephyr-app: samples/subsys/settings :host-os: unix :board: qemu_x86 :goals: run :compact: After running the image to the board the output on the console shows the settings manipulation messages. Sample Output ============= .. code-block:: console ***** Booting Zephyr OS build v2.1.0-rc1-123-g41091eb1d5e0 ***** *** Settings usage example *** settings subsys initialization: OK. subtree handler registered: OK subtree has static handler ############## # iteration 0 ############## ================================================= basic load and save using registered handlers load all key-value pairs using registered handlers loading all settings under handler is done loading all settings under handler is done save key directly: OK. load key-value pairs using registered handlers = -3025 loading all settings under handler is done save all key-value pairs using registered handlers export keys under handler export keys under handler load all key-value pairs using registered handlers export keys under handler export keys under handler ================================================= loading subtree to destination provided by the caller direct load: direct load: direct load: direct.length = 100 direct.length_1 = 41 direct.length_2 = 59 ================================================= Delete a key-value pair immediate load: OK. value exist in the storage delete : OK. Can't to load the value as expected ================================================= Service a key-value pair without dedicated handlers = 0 (default) save key directly: OK. ...