In the early days of controller area networks (CAN), every device manufacturer interpreted CAN frames in its own proprietary way. When you changed the engine of a harvester from Volvo to MAN, you would have to reimplement the communication with
The little known KDE Free Qt Foundation makes sure that Qt stays free and open-source. It guarantees that all Qt modules currently licensed under LGPLv3 must continue to be available under LGPLv3 in the future. This covers all modules from
Overdraw happens when one QML item fully eclipses another QML item. The QML renderer always draws both items, although there is no need to draw the eclipsed item. You must help out the renderer by explicitly setting visible: false on
The screenshot above shows the home screen of a sugar beet harvester. The home screen receives roughly 50 CAN messages per second and displays the contents of the CAN messages numerically or graphically. Every number on the home screen is
The mathematician Leopold Kronecker is believed to have said: God made the integers, all else is the work of man. And Kronecker didn't even know the floating-point numbers "made" for computers. Comparing two numbers of type
Today, I looked at the data-driven unit tests I had written nearly four weeks ago. It took me a couple of minutes to understand the tests again. Understanding my own tests should have been much easier. Data-driven unit tests in
When you write unit tests, you will have to compare the actual value and the expected value. A simplified example with QStrings would look like this. void MyTest::testQCompare() { auto actualStr = QString{"abba"}; auto expectedStr = QString{"juhu&
When you define your own C++ types for a Qt application, you want to print their values with qDebug(), qWarning() or qCritical() eventually. auto frame1 = QCanBusFrame{0x18ef0201U, QByteArray::fromHex("018A010000000000")}; qDebug() << "frame1 =" <<
The beginning of this month marked my sixth anniversary of becoming a solo consultant. I don't regret my decision and cannot imagine ever giving up solo consulting. I was essential in the implementation of some really interesting projects
In the first post of the Speaking CAN series, we learned how the terminal sends a read-parameter request to the ECU and how the ECU sends a response with the value of the parameter back to the terminal. This works
Controller Area Networks (CANs, for short) are used for the communication between electronic control units (ECUs) in cars, trucks, tractors, harvesters, construction machines, packaging lines and e-bikes. Qt provides the Qt CAN Bus API as part of its QtSerialBus module.
At Qt Day 2019 in Florence, Italy, I gave a talk Using Qt under LGPLv3. In the first part The obligations of Qt LGPLv3: made understandable, I explain in detail, how you must provide the source code, the license texts,