1============================= 2Espressif (ESP32 Chip Series) 3============================= 4 5LVGL can be used and configured as standard `ESP-IDF <https://github.com/espressif/esp-idf>`__ component. 6 7If you are new to ESP-IDF, follow the instructions in the `ESP-IDF Programming guide <https://docs.espressif.com/projects/esp-idf/en/stable/esp32/get-started/index.html>`__ to install and set up ESP-IDF on your machine. 8 9 10LVGL Demo Projects for ESP32 11---------------------------- 12 13For a quick start with LVGL and ESP32, the following pre-configured demo projects are available for specific development boards: 14 15- `ESP-BOX-3 <https://github.com/lvgl/lv_port_espressif_esp-box-3>`__ 16- `ESP32-S3-LCD-EV-BOARD <https://github.com/lvgl/lv_port_espressif_esp32-s3-lcd-ev-board>`__ 17- `M5Stack-CoreS3 <https://github.com/lvgl/lv_port_espressif_M5Stack_CoreS3>`__ 18 19Refer to the README.md files in these repositories for build and flash instructions. 20 21These demo projects use Espressif's Board Support Packages (BSPs). Additional BSPs and examples are available in the `esp-bsp <https://github.com/espressif/esp-bsp>`__ repository. 22 23 24Using LVGL in Your ESP-IDF Project 25---------------------------------- 26 27The simplest way to integrate LVGL into your ESP-IDF project is via the `esp_lvgl_port <https://components.espressif.com/components/espressif/esp_lvgl_port>`__ component. This component, used in the demo projects mentioned above, provides helper functions for easy installation of LVGL and display drivers. Moreover, it can add support for touch, rotary encoders, button or USB HID inputs. It simplifies power savings, screen rotation and other platform specific nuances. 28 29The esp_lvgl_port supports LVGL versions 8 and 9 and is compatible with ESP-IDF v4.4 and above. To add it to your project, use the following command: 30 31.. code:: sh 32 33 idf.py add-dependency "espressif/esp_lvgl_port^2.3.0" 34 35By default, esp_lvgl_port depends on the latest stable version of LVGL, so no additional steps are needed for new projects. If a specific LVGL version is required, specify this in your project to avoid automatic updates. LVGL can also be used without esp_lvgl_port, as described below. 36 37Obtaining LVGL 38~~~~~~~~~~~~~~ 39 40LVGL is distributed through `ESP Registry <https://components.espressif.com/>`__, where all LVGL releases are uploaded. 41In case you do not want to use esp_lvgl_port, you can add `LVGL component <https://components.espressif.com/component/lvgl/lvgl>`__ into your project with following command: 42 43.. code-block:: sh 44 45 idf.py add-dependency "lvgl/lvgl^9.*" 46 47Adjust the ``^9.*`` part to match your LVGL version requirement. More information on version specifications can be found in the `IDF Component Manager documentation <https://docs.espressif.com/projects/idf-component-manager/en/latest/reference/versioning.html#range-specifications>`__. During the next build, the LVGL component will be fetched from the component registry and added to the project. 48 49**Advanced usage: Use LVGL as local component** 50 51For LVGL development and testing, it may be useful to use LVGL as a local component instead of from the ESP Registry, which offers only released versions and does not allow local modifications. To do this, clone LVGL to your project with the following command: 52 53.. code-block:: sh 54 55 git submodule add https://github.com/lvgl/lvgl.git components/lvgl 56 57.. note:: 58 59 All components from ``${project_dir}/components`` are automatically added to build. 60 61Configuration 62~~~~~~~~~~~~~ 63 64To configure LVGL, launch the configuration menu with ``idf.py menuconfig`` in your project root directory. Navigate to ``Component config`` and then ``LVGL configuration``. 65 66 67Support for Display and Touch Drivers 68------------------------------------- 69 70For successful LVGL project you will need a display driver and optionally a touch driver. Espressif provides these drivers that are built on its `esp_lcd <https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-reference/peripherals/lcd/index.html>`__ component. 71 72- esp_lcd natively supports for some `basic displays <https://github.com/espressif/esp-idf/tree/master/components/esp_lcd/src>`__ 73- Other displays are maintained in `esp-bsp repository <https://github.com/espressif/esp-bsp/tree/master/components/lcd>`__ and are uploaded to ESP Registry 74- Touch drivers are maintained in `esp-bsp repository <https://github.com/espressif/esp-bsp/tree/master/components/lcd_touch>`__ and are uploaded to ESP Registry 75 76These components share a common public API, making it easy to migrate your projects across different display and touch drivers. 77 78To add a display or touch driver to your project, use a command like: 79 80.. code-block:: sh 81 82 idf.py add-dependency "espressif/esp_lcd_gc9a01^2.0.0" 83 84Using the File System under ESP-IDF 85~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 86 87ESP-IDF uses the standard C file operation functions (``fopen``, ``fread``) in all its storage related APIs. 88This allows seamless interoperability with LVGL when enabling the :c:macro:`LV_USE_FS_STDIO` configuration. 89The process is described in details below, using ``SPIFFS`` as demonstration. 90 91- **Decide what storage system you want to use** 92 93 ESP-IDF has many, ready-to-use examples like 94 `SPIFFS <https://github.com/espressif/esp-idf/tree/master/examples/storage/spiffsgen>`__ 95 , 96 `SD Card <https://github.com/espressif/esp-idf/tree/master/examples/storage/sd_card/sdspi>`__ 97 and 98 `LittleFS <https://github.com/espressif/esp-idf/tree/master/examples/storage/littlefs>`__ 99 . 100 101- **Re-configure your own project** 102 103 The example project should be examined for details, but in general the changes involve: 104 105 - Enabling LVGL's STDIO file system in the configuration 106 107 You can use ``menuconfig``: 108 109 - ``Component config → LVGL configuration → 3rd Party Libraries``: enable ``File system on top of stdio API`` 110 - Then select ``Set an upper cased letter on which the drive will accessible`` and set it to ``65`` (ASCII **A**) 111 - You can also set ``Default driver letter`` to 65 to skip the prefix in file paths. 112 113 - Modifying the partition table 114 115 The exact configuration depends on your flash size and existing partitions, 116 but the new final result should look something like this: 117 118 .. csv-table:: Partition Table 119 120 nvs, data, nvs, 0x9000, 0x6000 121 phy_init, data, phy, 0xf000, 0x1000 122 factory, app, factory, 0x10000, 1400k 123 storage, data, spiffs, , 400k 124 125 126 .. note:: 127 128 If you are not using a custom ``partition.csv`` yet, it can be added 129 via ``menuconfig`` (``Partition Table → Partition Table → Custom partition table CSV``). 130 131 - Apply changes to the build system 132 133 Some ESP file systems provide automatic generation from a host folder using CMake. The proper line(s) must be copied to ``main/CMakeLists.txt`` 134 135 .. note:: 136 137 ``LittleFS`` has extra dependencies that should be added to ``main/idf_component.yml`` 138 139- **Prepare the image files** 140 141 LVGL's ``LVGLImage.py`` Python tool can be used to convert images to binary pixel map files. 142 It supports various formats and compression. 143 144 Meanwhile 3rd party libraries 145 (like :ref:`LodePNG<lodepng_rst>` and :ref:`Tiny JPEG<tjpgd>`) 146 allow using image files without conversion. 147 148 After preparing the files, they should be moved to the target device: 149 150 - If properly activated a **SPIFFS** file system based on the ``spiffs_image`` folder should be automatically generated and later flashed to the target 151 - Similar mechanism for **LittleFS** uses the ``flash_data`` folder, but it's only available for Linux hosts 152 - For the **SD Card**, a traditional file browser can be used 153 154- **Invoke proper API calls in the application code** 155 156 The core functionality requires only a few lines. The following example draws the image as well. 157 158 .. code:: c 159 160 #include "esp_spiffs.h" 161 162 void lv_example_image_from_esp_fs(void) { 163 164 esp_vfs_spiffs_conf_t conf = { 165 .base_path = "/spiffs", 166 .partition_label = NULL, 167 .max_files = 5, 168 .format_if_mount_failed = false 169 }; 170 171 esp_err_t ret = esp_vfs_spiffs_register(&conf); 172 173 if (ret != ESP_OK) { 174 ESP_LOGE(TAG, "Failed to register SPIFF filesystem"); 175 return; 176 } 177 178 lv_obj_t * obj = lv_image_create(lv_screen_active()); 179 lv_image_set_src(widget, "A:/spiffs/logo.bin"); 180 lv_obj_center(widget); 181 } 182 183- **Build and flash** 184 185 After calling ``idf.py build flash`` the picture should be displayed on the screen. 186 187 188.. note:: 189 190 Changes made by ``menuconfig`` are not being tracked in the repository if the ``sdkconfig`` file is added to ``.gitignore``, which is the default for many ESP-IDF projects. 191 To make your configuration permanent, add the following lines to ``sdkconfig.defaults``: 192 193 .. code:: c 194 195 CONFIG_PARTITION_TABLE_CUSTOM=y 196 CONFIG_LV_USE_FS_STDIO=y 197 CONFIG_LV_FS_STDIO_LETTER=65 198 CONFIG_LV_FS_DEFAULT_DRIVER_LETTER=65 199