Transitioning from FreeRTOS to Zephyr RTOS - A Product Refresh Journey

Everything Open 2024 - Talk #68

• Location: Gladstone, QLD
• Date: April 16 - 18, 2024

[slides | conference site ]

Everything Open is Linux Australia’s premier conference on open technologies, welcoming anything from Linux, open-source software and hardware, to open data. This year, I had the privilege of presenting Audinate’s journey transitioning from FreeRTOS to Zephyr RTOS, focusing on how this change facilitated a much-needed product refresh.

Talk Overview

In my talk, I walked the audience through the transition from FreeRTOS to Zephyr RTOS within the context of our low-cost Dante product, a solution designed for professional AV networking.

The journey began with FreeRTOS, which had been at the heart of our product for years. However, as demand for more features grew—such as better audio encryption, cloud connectivity, and support for new audio formats—the limitations of FreeRTOS became apparent. This prompted the decision for a product refresh.

Key Challenges

• Resource Limits: Our existing FreeRTOS + MCU setup started hitting resource constraints, with the embedded stack struggling to keep up with the demands of new features.
• Supply Chain Issues: The MCU chip shortage between 2021 and 2023 further complicated matters, forcing us to rethink how tightly coupled our product was to specific hardware.

Why Zephyr RTOS?

We chose Zephyr RTOS because of its:

• Modularity & Portability: It allowed us to abstract the hardware layer and become more hardware-agnostic.
• Network & Connectivity: Given that Dante relies heavily on robust network performance, Zephyr’s strong native connectivity stacks (TCP/IP, Bluetooth, USB) were crucial.
• Security: Features like memory protection units (MPU/MMU), thread isolation, and stack overflow protection made Zephyr a clear winner for enhanced security.

Despite the challenges during development, including maturing the Zephyr TCP/IP stack to meet Dante’s demands, the vibrant Zephyr community proved to be a valuable resource for resolving bottlenecks and issues.

Outcome

As of 2024, we announced our beta release of the Dante Pro S1 series which is based on Zephyr RTOS, creating a future-proof product that supports the evolving needs of our industry. The move to Zephyr has paved the way for future iterations of Dante products, enabling more flexible and scalable solutions for professional AV environments.