C

STM32L4R9I Discovery Kit Setup Instructions

This topic helps you setup the development environment for STM's STM32L4R9I-Disco.

Board features

  • STM32L4R9AII6 MCU featuring ARM® Cortex®-M4, 2-MBytes Flash, 640-kbytes RAM
  • 1.2” 390x390 round Touch Display
  • 16-Mbit PSRAM memory
  • 512-Mbit Octo-SPI Flash memory

Setting up development environment

  • Ensure that the common STM prerequisites are met
  • Install STM32CubeL4 SDK 1.15.0 or newer (provided by the Qt online Installer).

Qt Creator IDE

  • Launch Qt Creator and select Tools > Options > Devices > MCU.
  • Select the Qt for MCUs 1.4 - STM32L4R9I-DISCOVERY-BAREMETAL 24bpp from the drop-down list for Target supported by the Qt for MCUs SDK.
  • Provide the STM32CubeProgrammer install path if it is not installed in the default location.
  • In the Requirements section, ensure that the platform-specific requirements are met.
  • Select Create Kit to create a kit for the selected target. if a kit already exists, remove it first using Remove Kit.

    Note: If you don't see the option to create a kit, check your settings in the Requirements section.

  • Click Apply.

Command line setup

To get started from the command line, ensure that the following these instructions:

  • Qul_DIR to the Qt for MCUs SDK install path.
    <QT_INSTALL_PATH>\QtMCUs\<VERSION>

    where,

    • <QT_INSTALL_PATH> is the Qt install directory,
    • and <VERSION> is the directory containing the Qt Quick Ultralite version you are using, for example 1.1.0.
  • ARMGCC_DIR to the ARM Toolchain install path.
  • Add the CMake and Ninja tools to your system PATH. If you installed these tools using the Qt online installer, they are installed under <QT_INSTALL_PATH>\Tools.
  • Add STM32CubeProg install directory to System PATH if it is not installed in the default location.
  • Add ST-LINK_gdbserver.exe directory to your System PATH
    <STM32_CUBE_IDE_INSTALL_PATH>\stm32cubeide_1.3.0\plugins\com.st.stm32cube.ide.mcu.externaltools.stlink-gdb-server.win32_1.3.0.202002181050\tools\bin

    where, <STM32_CUBE_IDE_INSTALL_PATH> is the Cube IDE install path.

    Note: STM32CubeIDE is optional and required only for on-chip debugging purposes.

  • Create the STM32Cube_FW_L4_SDK_PATH environment variable and set it to:
    <QT_INSTALL_PATH>\Tools\QtMCUs\STM\STM32Cube_FW_L4_V<version>

    where, <QT_INSTALL_PATH> points to the Qt install directory.

Build configuration

Qt Creator provides a build configuration with the kit that you created earlier for the Qt for MCUs 1.4 - STM32L4R9I-DISCOVERY-BAREMETAL 24bpp target. If you are using a command line setup, configure using the following CMake variables. For more information, see the CMake Manual.

  • QUL_PLATFORM

    The platform to build must be set to stm32l4r9i-discovery-baremetal for this board.

    -DQUL_PLATFORM=stm32l4r9i-discovery-baremetal
  • CMAKE_TOOLCHAIN_FILE

    This platform supports armgcc compiler.

    -DCMAKE_TOOLCHAIN_FILE=%Qul_DIR%\lib\cmake\Qul\toolchain\armgcc.cmake
  • QUL_COLOR_DEPTH

    The supported color depth by this platform is 24-bit.

    Note: If this variable is not set, default color depth is used while configuring for the platform.

    -DQUL_COLOR_DEPTH=24
  • QUL_COPY_TO_RAM

    By default, the asset data for application is copied to SDRAM on application startup. In order to keep resources in external flash, and not load it to RAM on startup, use the QUL_COPY_TO_RAM CMake option with the value Never when adding assets to the application with qul_add_resource.

Prebuilt demos and examples

The package for STM32L4R9I_DISCO board comes with a prebuilt watch demo binary. You can find it in the demos_images directory.

See Flashing Instructions for ST boards, for information about flashing the device.

For this board, select MX25LM51245G_STM32L4R9I-DISCO as the external loader.

Demos and examples source code

Qt for MCUs provides the source code of several demos and examples. You can modify, build, and flash custom binaries onto the target device.

Source code for supported demos and examples is organized in the following directory structure:

Note: Demos or examples that are highlighted in bold are the only ones supported on this board.

Building applications with prebuilt Qt Quick Ultralite libraries

Qt Creator IDE

Open the CMake project file for the example you want to build and configure it with the kit you created earlier. Once the project is configured, select Run or press Ctrl+r on your keyboard to build and flash the binary to the target.

Command line

The following example builds the watch demo for this board:

cd %Qul_DIR%\demos\watch
mkdir build
cd build
cmake .. -G "Ninja" -DCMAKE_BUILD_TYPE=Debug -DCMAKE_TOOLCHAIN_FILE=%Qul_DIR%\lib\cmake\Qul\toolchain\armgcc.cmake -DQUL_PLATFORM=STM32L4R9I-DISCOVERY-baremetal
cmake --build .

Once you have successfully built the watch demo, you can flash it from command line:

cmake --build . --target flash_watch

The same procedure applies to any other application.

Building Qt Quick Ultralite

If your license provides access to the Qt Quick Ultralite sources, build it with all of supported demos/examples. Run the following commands from the terminal window:

cd %Qul_DIR%
mkdir build
cd build
cmake .. -G "Ninja" -DCMAKE_BUILD_TYPE=Debug -DCMAKE_TOOLCHAIN_FILE=..\lib\cmake\Qul\toolchain\armgcc.cmake -DQUL_GENERATORS=..\lib\cmake\Qul\QulGenerators.cmake -DQUL_PLATFORM=STM32L4R9I-DISCOVERY-baremetal

Once Qt Quick Ultralite is built successfully, you can flash the supported demos/examples from command line.

cmake --build . --target flash_<DEMO_OR_EXAMPLE_NAME>

Where, DEMO_OR_EXAMPLE_NAME is the name of a supported demo/example.

Building applications using a custom built Qt Quick Ultralite

This section describes how to build an application, using a custom Qt Quick Ultralite build.

  • First, you must set up the development environment as described earlier.
  • Build Qt Quick Ultralite from the modified sources and install it to a custom location.
    mkdir some\path\custom_builds\qul
    cd some\path\custom_builds\qul
    
    mkdir qul-build
    cd qul-build
    
    cmake <PATH_TO_INSTALLED_QT_SDK>\QtMCUs\<version> \
          -G "Ninja" \
          -DCMAKE_INSTALL_PREFIX=some\path\custom_builds\qul \
          -DCMAKE_BUILD_TYPE=Release \
          -DCMAKE_TOOLCHAIN_FILE=<PATH_TO_INSTALLED_QT_SDK>\QtMCUs\<version>\lib\cmake\Qul\toolchain\armgcc.cmake \
          -DQUL_PLATFORM=<PLATFORM_NAME> \
          -DQUL_BUILD_TESTS=OFF \
          -DQUL_BUILD_DEMOS=OFF \
          -DQUL_BUILD_EXAMPLES=OFF \
          -DQUL_GENERATORS=<PATH_TO_INSTALLED_QT_SDK>\QtMCUs\<version>\lib\cmake\Qul\QulGenerators.cmake \
    
    ninja install
  • Use the custom Qt Quick Ultralite to build your application, which is not part of the Qt Quick Ultralite source tree:
    cd some\path\custom_builds
    mkdir app # Put your application here. You can use the redbutton example from the SDK.
    cd app
    mkdir build
    cd build
    
    set QUL_DIR=some\path\custom_builds\qul
    cmake .. \
          -G "Ninja" \
          -DCMAKE_BUILD_TYPE=Release \
          -DCMAKE_TOOLCHAIN_FILE=some\path\custom_builds\qul\lib\cmake\Qul\toolchain\armgcc.cmake \
          -DQUL_GENERATORS=<PATH_TO_INSTALLED_QT_SDK>\QtMCUs\<version>\lib\cmake\Qul\QulGenerators.cmake \
          -DQUL_PLATFORM=<PLATFORM_NAME> \
    
    ninja
    ninja flash_<YOUR_APP_NAME>

Reading debug messages

By default, the output of printf calls are redirected to a virtual serial port, which is exposed on the host machine via USB.

Debugging

  • Open terminal window and run the following command:
    ST-LINK_gdbserver.exe -cp "<STM32_CUBE_PROG_INSTALL_PATH>\bin"

    where, <STM32_CUBE_PROG_INSTALL_PATH> is the directory where you've installed the Cube Programmer tool.

    GDB Server is now listening for TCP connections on the default port, 61234.

    Note: Actual TCP port used by ST-LINK_gdbserver is printed out on gdbserver's console.

  • Run arm-none-eabi-gdb in a separate console
    %ARMGCC_DIR%\bin\arm-none-eabi-gdb.exe <PATH_TO>\your_app.elf
  • Connect to the target via the gdbserver in the arm-none-eabi-gdb console using
    (gdb) target remote 127.0.0.1:61234

Troubleshooting

ST-LINK_gdbserver requires up-to-date ST-LINK firmware to be installed. If you see the following error:

Error in initializing ST-LINK device. Reason: ST-LINK firmware upgrade required.

you must upgrade the firmware to the latest version using the STM32CubeProgrammer tool.

If the problem persists after upgrade, retry with ST-LINK Upgrade tool from the ST webpage ( Download ).

Known limitations

STM32L4R9AII6 MCU does not have double precision floating point support. Care should be taken to avoid using them.

Available under certain Qt licenses.
Find out more.