embedded systems

EU CRA: Essential Requirements Related to Product Properties

by Burkhard Stubert
2025/01/172025/06/06
4 Comments

Every manufacturer must implement the essential requirements in Annex 1 Part 1 of the EU CRA in their products. They must also document how they comply with the essential requirements in a conformity assessment. The wording of the essential requirements is very generic and hard to understand. Germany’s Federal Office of Information Security (BSI) published a Technical Guideline (PDF) that translates the legalese of the EU CRA into concrete and actionable requirements. I will add lots of examples from my work with embedded Linux devices to illustrate the requirements.

Embedded Devices Covered by EU Cyber Resilience Act (CRA)

by Burkhard Stubert
2024/11/192025/05/28

Which devices are covered by the EU Cyber Resilience Act (EU CRA)?

An X-ray fluorescence (XRF) analyser connected with the Internet over WiFi.
A metal-sheet bending machine with an Ethernet port, which will only be used in the future.
The harvester ECUs connected over CAN bus.
A camera trap without any connectivity, where updates and photos are exchanged via SD card.
A full-body 3D X-ray scanner used by doctors.

The commands for updating u-boot using an A/B strategy

Updating U-Boot with an A/B Strategy

by Burkhard Stubert
2024/05/132024/05/13
5 Comments

Unlike consumer devices, machines, ECUs or medical devices are in the field for 15 or more years. There inevitably comes the time in their life, when you must update their boot loader. I’ll show you how to do this from an embedded Linux system running on an NXP iMX8M Plus. You can adapt the method to other SoCs and use it for OTA updates, as well.

Installing Linux Images on Toradex Verdin Boards

by Burkhard Stubert
2022/10/312025/05/07

In the post Setting Up Yocto Projects with kas, we built the Linux image for the Toradex Verdin iMX8M Plus. It’s time to flash the image on the board using the Toradex Easy Installer (TEZI). It’s a three-step procedure: wire up the board in a special way, install and run TEZI on the board, and flash our custom-built Linux image from a USB drive on the board.

Applying TDD to HAL Drivers with Memory-Mapped I/O

by Burkhard Stubert
2022/08/032022/08/11

A client recently asked me to help them get a legacy HAL driver under test. They want to use TDD to maintain and extend the driver. We ran into a couple of problems, because the tests run on a 64-bit computer, whereas the production code runs on a 32-bit microcontroller. I’ll explain the problems and how to solve them.

Visualising the Architecture of Qt Embedded Systems: Context and Container Diagrams

by Burkhard Stubert
2022/07/112022/07/11
2 Comments

I never got the hang of UML: overly complicated, hard to understand, too close to code. Hence, I was skeptical about C4 diagrams when I… Read More »Visualising the Architecture of Qt Embedded Systems: Context and Container Diagrams