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HMI
In this blog, I would like to provide a small Qt-Quick application (qml) as an example for a Modbus connection via TCP/IP. In the Qt examples, I only found QWidget examples for Modbus connections, and after recently creating a Qt Quick application for this purpose, I would like to provide a scaled…
HMI
Introduction This is a guide for configuring Qt Creator in order to be able to use cross-compiled Qt libraries for the Raspberry Pi 4 and create applications for the Raspberry. Requirements Raspberry Pi OS Lite Install Raspberry Pi OS Lite on a Raspberry Pi 4 or on a Raspberry Compute Module 4…
HMI
Introduction This is a guide for cross-compiling Qt 5.15.2 for Raspberry Pi 4 and installing it on Compute Module 4. It is an update to my blog post Qt on the Raspberry Pi 4, with the difference that this time I am using Raspberry Pi OS Lite (download here: https://www.raspberrypi.org/software/…
HMI
Introduction This is a guide for installing Raspberry Pi OS Lite on the Compute Module 4. For my working computer, I use Ubuntu 20, installed on a virtual machine. Sources For these instructions, I have been strongly guided by the description by Jeff Geerling: - Jeff Geerling: https://www.…
HMI
Qt is often used to develop graphic interfaces. Qt contains C ++ libraries for creating graphical interfaces that can be compiled on various operating systems. Since this compilation requires a lot of computing power, it is advisable for processors with relatively little power to carry out the…
HMI
I recently had to develop an application (kiosk system) for/on a Raspberry Pi 4. The special thing about it was that 2 touch monitors were to be connected via HDMI, which also had to be rotated 90 degrees to the right.
HMI
Frequent writing or overwriting of data negatively affects the lifespan of an SD card. For applications that often use temporary data (e.g., sensor values for comparative calculations) that are no longer required after a restart, it is therefore advisable to write these to a RAM disk. Another…
HMI
If you have created a Qt application – or any other application – for the Raspberry Pi 4, you will very often want to have the application called up immediately after the Raspberry is restarted, once you have completed the application. This is often attempted using start scripts, which can be…
HMI
The task was to write a Qt Quick application (GUI) to upload new firmware to a touch controller. The upload software was provided by the manufacturer in a .exe application that loads a .bin file onto the touch controller. I wanted to use the "QProcess" Qt classes for this, which can be used to call…
HMI
The aim was to write a Qt application for the Raspberry Pi 4 with which you can switch between different WLAN access points and save the associated credentials. As a starting point, I used a raspbian-buster-lite image and a Qt installation as described in Qt on the Raspberry Pi 4. I also installed…