Particle Device OS Updates Thread

Device OS 4.0.1 LTS is available in the Web IDE, Particle CLI and Workbench for (Argon/Boron/B SoM/B5 SoM/Tracker/E SoM X).

Released on November 14th, 2022

Note: This is a Release and may be used for production. This is the second Release in the Device OS release 4.x line (LTS) with critical bugfixes and backports from 5.x release line

To learn more about LTS release line, read our blog post.

You can view information about Device OS versions, upgrades and downgrades here.

Gen 3 256KB application binary support

Device OS v3.1.x and further releases bring support for 256KB application binaries to all Gen 3 platforms (at that time: Argon, Boron, B SoM, B5 SoM, Tracker). A few important aspects of this change:

  1. Compatibility with 128KB applications built with < Device OS 3.1 versions is maintained. Devices can still run them even if other parts have been upgraded to Device OS 3.1+.
  2. Upgrade process OTA (including product-based upgrades) is transparent.
  3. When upgrading locally (using DFU or Serial), make sure to update the bootloader first, as it has some logic managing compatibility between 128KB and 256KB application types. See this page on steps how to perform the update.
  4. If using standalone Particle CLI installation, make sure it’s updated to >= 2.12.0 version, which includes support for 256KB applications.



  • [wiring] ApplicationWatchdog: fixes potential 2x timeout required to fire #2536
  • [gen3]Fix BLE control request channel sending malformed packets #2538
  • Fix issue with platform_ncp_get_info(0) for quectel platforms #2532
  • Secures DCT initialization from getting interrupted between creating DCT file and filling it with 0xff to default state #2530
  • [Boron / B SoM] R410 PPP crash in network phase workaround #2571
  • [Cellular] R410 initialization SIM failure workaround #2573


  • Use new prtcl compile/clean commands for internal CI builds #2543
  • Increase timeouts for internal CI builds on windows #2545
  • HAL wiring api calls to access exflash read/write functions for OTP flash page #2540
  • [hal] wifi: add generic ‘world’ country code as not every country code is exposed through API #2539

System Binaries (all devices)

Programming and Debugging

You can view specific programming and debugging notes for this version of firmware here.


release/stable and master branches have been updated to point to v4.0.1 tag.