Changes

I'm excited to announce the first release of 2026. There has been a lot of internal reorganization to standardize LED functionality across Zigbee, Thread, and Zigbee router firmwares for the ZBT-2 and to prepare the codebase for the eventual migration from Silicon Labs Gecko SDK to Simplicity SDK.

General

• The firmware builder has been entirely Dockerized and is now natively compatible with both ARM and x86-64 hosts. You can clone this repo test your own firmware tweaks in 30 seconds with a single command!

Zigbee

• A Zigbee router firmware for the ZBT-2! Try it out by flashing the GBL file below using the OHF Device Toolbox for the ZBT-2. Hold down the pinhole reset button on the back of the ZBT-2 to reset it and get it to join a new network.
• The network activity LED has been re-enabled for the Yellow.
• An experimental feature is now enabled to allow ZHA to quickly restore network routes on startup,

Thread

• OpenThread RCP firmware for all adapters has migrated from Gecko SDK 4.5.0 to the latest release of Simplicity SDK.
• The ZBT-2 LED now pulses during setup, before a network has been formed.

What's Changed

• XNCP command: read chip info by @puddly in #121
• Merge stable into dev by @puddly in #131
• slsdk file for extension and debian image bump for CI by @Szewcson in #130
• Switch to new URLs for SiLabs tools by @puddly in #132
• Create a tool to generate combined bootloader + application + tokens HEX by @puddly in #135
• Allow manually managing the route table by @puddly in #118
• Gecko SDK 4.5.0 by @puddly in #138
• Dual GPIO bootloader trigger by @puddly in #143
• Move drivers into dedicated SDK components by @puddly in #151
• Move all XNCP commands into components by @puddly in #152
• Port reset button component from stable to main by @puddly in #153
• Align LED behavior between OpenThread and Zigbee firmwares by @puddly in #154
• Drop Z-Wave source code by @puddly in #155
• Use Simplicity SDK v2025.6.2 for OpenThread RCP firmware by @puddly in #156
• Merge stable into main by @puddly in #157
• Fix Yellow Zigbee activity LED by @puddly in #158
• Set PCLK_DIVIDER instead of DEFAULT_HF_CLOCK_SOURCE for Yellow OT-RCP config by @puddly in #160
• Export a sl_led-compatible interface for the WS2812 API by @puddly in #161
• OpenThread: Use EUSART peripheral instead of USART for MG24 by @puddly in #162
• LED manager component and WS2812B temporal dithering by @puddly in #163
• Create factory HEX files out of GBL files by @puddly in #165
• Switch from 32-bit to 4×8-bit lookup table for WS2812 bit patterns by @puddly in #166
• Docker entrypoint by @puddly in #168
• Zigbee router firmware for ZBT-2 by @puddly in #164
• Swap build system from Makefiles to CMake + Ninja by @puddly in #169
• Tag containers when merging by @puddly in #170

New Contributors

• @Szewcson made their first contribution in #130

Full Changelog: v2025.11.24...v2026.01.11-beta1