Open Sigfox Stack for STMicroelectronics S2-LP

Late last year I published librenard, an open-source Sigfox stack implementation based on my reverse engineered Sigfox specifications. In the meantime, Sigfox have also officially opened their specs, confirming my own research.

librenard was written with portability in mind, making it possible to run it both as part of a tool such as renard (CLI encoder / decoder for Sigfox) as well as part of microcontroller applications. However, there have not been any attempts to actually use librenard on a microcontroller together with a dedicated RF transceiver IC so far (at least that I am aware of).

This is changing now with the release of renard-phy-s2lp, which integrates librenard with a driver for the STMicroelectronics S2-LP ultra-low power RF transceiver. Thanks to interchangeable hardware abstraction layers, renard-phy-s2lp is independent of the microcontroller platform. So far, it has been tested with an STM32L0 development board (STEVAL-FKI868V2) and Espressif’s ESP32.

renard-phy-s2lp, the hardware abstraction layers and demo applications are all permissively licensed, so feel free to embed them in your IoT application. I’d still be happy to merge any improvements you make upstream!