Introduction to Zephyr Part 3: Kconfig Tutorial | DigiKey

Configuring embedded systems can feel overwhelming, especially when dealing with complex frameworks like Zephyr. In this video, we’ll break down the fundamentals of Kconfig and show you how to leverage menuconfig, a powerful text-based interface for enabling and disabling various features in your firmware. By the end, you’ll have a deeper understanding of how to tailor your embedded application’s behavior without hardcoding options into your source files. You can find a written version of this tutorial here: https://www.digikey.com/en/maker/tutorials/2025/introduction-to-zephyr-part-3-kconfig-tutorial The GitHub repository for this course (including solutions to the challenges) can be found here: https://github.com/ShawnHymel/introduction-to-zephyr/tree/main We’ll start by creating a simple random number generator application, then walk through the process of resolving build errors caused by missing Kconfig symbols. You’ll learn how to navigate menuconfig, search for relevant configuration options, and enable or disable them to ensure your code compiles and runs as expected. This step-by-step approach helps demystify Zephyr’s configuration system and makes it easier to handle large-scale embedded projects. Next, we’ll discuss how to manage multiple configuration files. We’ll show you how to separate general app settings from board-specific overrides via .conf files, making it simpler to handle multiple targets without constantly editing configuration files. In addition to the Devicetree, this helps keep your application code portable among various embedded systems. Along the way, we’ll highlight the workflow for preserving configuration changes and how to use Kconfig tools like diffconfig to track symbol modifications. Building on this foundation, we’ll demonstrate how to create custom Kconfig symbols in a separate module. This approach allows you to conditionally compile code, adding or removing features at build time. It’s a powerful way to keep your application modular, maintainable, and easy to adapt as your requirements evolve. Whether you’re enabling pseudo-random number generation, exploring true hardware entropy sources, or integrating custom modules, this tutorial arms you with the knowledge you need to master Zephyr’s configuration system. By the end, you’ll be confident in using Kconfig and menuconfig to streamline your workflow, reduce complexity, and keep your embedded development on track.