| .. zephyr:code-sample:: lvgl-accelerometer-chart |
| :name: LVGL line chart with accelerometer data |
| :relevant-api: display_interface sensor_interface |
| |
| Display acceleration data on a real-time chart using LVGL. |
| |
| Overview |
| ******** |
| |
| A sample application that demonstrates how to use LVGL and the :ref:`sensor` to |
| display acceleration data on a line chart that is updated in real time. |
| |
| This sample creates a line chart with three series, one for each axis of the accelerometer. An LVGL |
| timer fetches the latest acceleration data from the sensor every 20 ms (default value) and updates |
| the chart. The update period is configurable, see |
| :ref:`lvgl_accelerometer_chart_building_and_running` below. |
| |
| Requirements |
| ************ |
| |
| * A board with a display. |
| * A sensor that provides acceleration data (:c:enumerator:`SENSOR_CHAN_ACCEL_XYZ`) and available |
| under the ``&accel0`` Devicetree alias. |
| |
| .. note:: |
| |
| A Devicetree overlay declaring an emulated BMI160 accelerometer is provided for the |
| ``native_posix*`` and ``native_sim*`` board variants, making it possible to run this sample on |
| your local machine. |
| |
| .. _lvgl_accelerometer_chart_building_and_running: |
| |
| Building and Running |
| ******************** |
| |
| The maximum number of points to display for each series and the sampling rate of the |
| accelerometer can be configured using the :kconfig:option:`CONFIG_SAMPLE_CHART_POINTS_PER_SERIES` |
| and :kconfig:option:`CONFIG_SAMPLE_ACCEL_SAMPLING_RATE` Kconfig options, respectively. |
| |
| The default sampling rate is 50 Hz, and the default maximum number of points per series is 50. |
| |
| The demo can be built as follows (note how in this particular case the sampling rate is set to a |
| custom value of 20 Hz): |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/modules/lvgl/accelerometer_chart |
| :host-os: unix |
| :board: native_sim |
| :gen-args: -DCONFIG_SAMPLE_ACCEL_SAMPLING_RATE=20 |
| :goals: run |
| :compact: |
