Examples using Zephyr RTOS on ST STM32F429I Discovery board using PlatformIO IDE

This repository contains examples of codes used in teaching, particularly at ESIEA.

4 examples are proposed:

• NoGUI - Using the 2 LEDs on the board and the button.
  • 3 tasks are created:
    • 1 task per LED with sporadic lighting (using k_msleep)
    • 1 task allowing lighting the 2 LEDs when the button has been pressed (using interruption).
  • An overlay is defined to show how to add the declaration of a new external LED, not used in the proposed code.
• WithGUI - Using the board screen, touch interface, an image and an external sensor BME680 connected in I2C. Temperature and humidity values are added to a chart and regularly printed on the screen using labels.
  • Screen:
    • The LVGL library is used, from the Zephyr framework.
    • The appropriate configuration is made in the .conf file of the project, in particular to activate the management of:
      • SENSORS and in particular the BME680 driver
      • DISPLAY
      • INPUT
      • LVGL and its components (buttons, charts, labels, etc.)
      • Debugging with SEGGER SystemView available on the SWD connector.
    • The appropriate configuration is made in the .conf file of the board, in particular to activate the management of:
      • ILI9341 driver used by the screen,
      • I2C used by the BME680.
    • An overlay is defined to specify that the BME680 is connected to I2C 3 of the board, with address 0x77.
• PeriodicTasks - Creation of 2 periodic tasks (using timers) with display on the LEDs integrated into the board and with a configurable duration (use of 'nop' to simulate the use of the processor).
• Samples - No task used, only example using DISPLAY, INPUT, BME680, SERVO and ADC (:warning: only one channel is used on SMT32 and this version of Zephyr).

Some details on versions used:

Tool	Version
PlatformIO (PIO)	Core 6.1.16 - Home 3.4.4
Zephyr RTOS	3.6.0 (See all versions available for PIO here)
LVGL	8.3.11 (linked with Zephyr 3.6.0, see Changelog

Some useful links about the board:

Link	Details
ST STM32F429I Discovery	Details of the board on Zephyr doc
ST STM32F429I Discovery Pin Mapping	Pin mapping of the board, from MBED doc
ST STM32F429I Discovery Zephyr conf	Folder in Zephyr defining the board details
ST STM32F429I Discovery Zephyr DTS	DTS file in Zephyr defining the board details

Some useful links about the Zephyr:

Link	Details
Zephyr Devicetree (DTS) and Overlay principles 1 2	Details on how to use DTS and overlays
Basic Display	Example using basic Display code on Zephyr
LVGL	Example using LVGL and Display code on Zephyr
Zephyr Threads	Doc on Thread in Zephyr
Sleep and periodic tasks	Discussion on how to create periodic tasks on Zephyr

TODO

• update the ADC integration using overlay.
• see examples of teaching resources using Zephyr:
  • https://academy.nordicsemi.com/topic/exercise-3-7/
• Add example in "Samples" with a module, see the work of lilaiguernelala during her internship at ESIEA.