SLD Demo

This software demonstrate the usage of the SLD display series from Schukat using the esopublic library. With the SLD_C_W_S3 microcontroller board of ESoPe.

The displays have can be connected to the board and used without any software change, regardless of the display size. The SLD_C_W_S3 supports the displays from 2.4" (320 x 240) to 5" (800 x 480). The board itself is driven by ESP32-S3-WROOM-1(U)-N16R8, which is a dual core Xtensa MCU with up to 240 MHz clock frequency. The board has a connector for power supply, a connector for the display and a connector for a piggy back PCB with 2 GPIOs. This enable the piggy back to make use of UART, RS485, CAN (TWAI) or I2C.

Build

The software is built using ESP-IDF 5.2 or 5.4. We recommend using VsCode with the ESP-IDF Extension for easy installation and usage of the espressif compiler. You can compile it either with the vscode function for compiling the esp-idf or by using the esp-idf prompt with the idf.py build command.

The default sdkconfig is set to ESP-IDF 5.2. There are also sdkconfig samples for ESP-IDF 5.4 as well as an sdkconfig for ESP32-P4 board (work in progress).

UI generation

This demo shows how to use UI frameworks Slint and LVGL with the display series. Both have there advantages and you can decide for yourself which one you want to use. The default configuration of this project uses Slint.

Slint

To use slint you have to make the following configuration:

/CMakeList.txt

# Make sure this is defined and set to true
set(KERNEL_ADD_DEPENDENCY_SLINT true)

main/idf_component.yml

dependencies:
  esope-gmbh/esopublic: "^24.1.0"
  slint/slint: "^1.8.0"
  idf:
    version: ">=5.2.0"

By enabling this configuration, the CMakeList.txt of esopublic sets a compiler define "KERNEL_USES_SLINT", which is checked internally and enables the main/app_ui_slint.cpp to use for the UI configuration. The main/ui directory contains the slint files, which are used to create the user interface.

LVGL

To use LVGL you have to make the following configuration:

/CMakeList.txt

# Make sure this line is commented or deleted
# set(KERNEL_ADD_DEPENDENCY_SLINT true)
# Is needed for generated image files to work directly
add_compile_definitions(LV_LVGL_H_INCLUDE_SIMPLE=1)
# This is needed for 5" display, to work propertly
add_compile_definitions(DISPLAY_NUM_FB=2)

main/idf_component.yml

dependencies:
  esope-gmbh/esopublic: "^24.1.0"
  lvgl/lvgl: "^9.1.0"
  idf:
    version: ">=5.2.0"

sdkconfig:

CONFIG_LCD_RGB_RESTART_IN_VSYNC=y
CONFIG_GDMA_CTRL_FUNC_IN_IRAM=y
CONFIG_COMPILER_OPTIMIZATION_PERF=y
CONFIG_LV_FONT_MONTSERRAT_10=y
CONFIG_LV_FONT_MONTSERRAT_14=y
CONFIG_LV_FONT_MONTSERRAT_24=y

By enabling this configuration, the CMakeList.txt of esopublic sets a compiler define "KERNEL_USES_LVGL", which is checked internally and enables the main/app_ui_lvgl.c to use for the UI configuration. The main/ui_lvgl directory contains assets to use for creating the lvgl user interface.

To prevent the display "drifting" (especially with 5" display), you should apply the sdkconfig changes above.