There’s a new article at the Linux Foundation on Developing Bluetooth Low Energy applications with Zephyr RTOS: Dissecting an iBeacon example.
This article is more useful than it might first seem. Zephyr isn’t just another Linux operating system (OS) but is the chosen OS for developing Nordic Semiconductor’s latest system on a chip devices (SOCs) that form the basis of the majority of shipping Bluetooth beacons. Previously, Nordic Semiconductor had their own OS delivered through nRF5 SDKs but development is being moved to the Zephyr-based nRF Connect SDK.
The iBeacon article explains how to broadcast an iBeacon advertisement and what to change to alter the various Bluetooth advertising parameters.