SBC Lynx SBC/Getting started with Qt Creator

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This application note has been validated using the kit version in the History table.

History

Version	Date	Development Kit version
1.0.0	Jun 2021	DESK-MX6UL-L 1.0.1

Introduction

This application note details QT Creator setup and configuration in DESK MVM

Setting up Qt Creator to build for DESK

Note: The NXP BSP 4.14.98 includes Qt 5.10.1 so the following instructions has been created using Qt Creator 4.5.1 included in the qt-opensource installer for this Qt version.

Qt Creator Installation

The qt-opensource-linux installer can be downloaded form the Qt download http site, i.e. from this link.

dvdk@vagrant:~/desk-mx-l$ wget https://download.qt.io/new_archive/qt/5.10/5.10.1/qt-opensource-linux-x64-5.10.1.run

To install Qt Creator inside your toolchain launch a terminal emulator and run

dvdk@vagrant:~$ cd desk-mx-l/

dvdk@vagrant:~/desk-mx-l$ ./qt-opensource-linux-x64-5.10.1.run 

An installation wizard will appear. Clik Next to proced with the installation.

Fill the form with your information and properly activate your account on Qt web site.

Select Next.

Select the install directory or click Next.

Select Next.

After carefully reading the License Agreement, if you agree, accept it and then press Next again.

And then click Install and complete the installation.

Then Finish to exit the setup wizard.

Manual configuration

In this section we details all the step required for configuring the SDK toolchain.

Devices

Go to Tools -> Options menu

Select Devices and click Add

Choose the Generic Linux device

Insert the IP address of your device, root as username and leave password empty (this is the default configuration of DESK root file systems). Make sure that the device is connected to the network and your virtual machine networking is correctly configured (see this article for more details).

Then click Next.

If everything went ok pressing Finish button you should see a dialog like the image below.

And finally this is how the Devices window should look like.

GCC & Cross Compilation

Next you need to configure the cross compilation tool inside Build & Run -> Compiler.

Click Add -> GCC, add the compiler path and set (for example) the DESK-MX-GCC compiler name.

/home/dvdk/desk-mx-l/sdk/latest_desk-mx6ul-l/sysroots/x86_64-pokysdk-linux/usr/bin/arm-poky-linux-gnueabi/arm-poky-linux-gnueabi-gcc

And click Apply.

Do the same for the C++ cross compilation tool (DESK-MX-GCC+)

/home/dvdk/desk-mx-l/sdk/latest_desk-mx6ul-l/sysroots/x86_64-pokysdk-linux/usr/bin/arm-poky-linux-gnueabi/arm-poky-linux-gnueabi-g++

Debugger GDB

Now it is necessary to add a debugger. In order to do this go to the Debuggers tab and click Add.

And then select the GDB debugger at the location

/home/dvdk/desk-mx-l/sdk/latest_desk-mx6ul-l/sysroots/x86_64-pokysdk-linux/usr/bin/arm-poky-linux-gnueabi/arm-poky-linux-gnueabi-gdb

and click Apply.

Qt Version

Next you need to add the Qt Version installed on your device. Go to Qt Version click Add and select the following qmake file.

home/dvdk/desk-mx-l/sdk/latest_desk-mx6ul-l/sysroots/x86_64-pokysdk-linux/usr/bin/qt5/qmake

Kits

The last step is to add a new kit. Go to Kits and click Add and complete the information as shown below.

Pay attention that in Qt mkspec you need to write

linux-oe-g++

After this your setup is complete and you can proceed and create your Qt applications.

Qt application example

Now that the setup is finished, you can create your first application

Open a new terminal and source the environment variables with the command.

dvdk@vagrant:~/desk-mx-l$ source desk-mx6ul-l-1.0.1_env.sh 

In the same terminal type the following command (we assume you didn't change the default installation directory)

dvdk@vagrant:~/desk-mx-l$ /home/dvdk/Qt5.10.1/Tools/QtCreator/bin/qtcreator

It is important to repeat the previous two step every time you start QTCreator

Now click on New Project, select Application Qt Widgets Application and click Choose...

Now call the Project Test and press Next.

Select the DESK Kit and click Next.

Choose the class name for your application.

Click Finish to conclude the setup.

To add a clickable button to your application, select the Edit window and select Test -> Forms -> mainwindow.ui

Click on Push Button in the Buttons tab and drag it to the main window view. In order to edit the text displayed by the label, double click it and write "Hello World!".

After that, you need to insert the following two line inside the Test.pro file

target.path = /tmp/Test # path on device

INSTALLS += target

Where /temp/Test is the path in which your application will be downloaded inside the device.

The last step before running the application inside the device is to configure Qt backend into application command line arguments: open the Project window and select the Run configuration, then type -platform linuxfb into Arguments

After these changes you are ready to debug your application inside your board with the Run/Debug command