nRF Connect SDK v2.6.1 Release Notes

nRF Connect SDK delivers reference software and supporting libraries for developing low-power wireless applications with Nordic Semiconductor products in the nRF52, nRF53, nRF70, and nRF91 Series. The SDK includes open source projects (TF-M, MCUboot, OpenThread, Matter, and the Zephyr RTOS), which are continuously integrated and redistributed with the SDK.

Release notes might refer to “experimental” support for features, which indicates that the feature is incomplete in functionality or verification, and can be expected to change in future releases. To learn more, see Software maturity levels.

Highlights 

This patch release adds changes on top of the nRF Connect SDK v2.6.0. The changes affect Matter, Wi-Fi®, Thread, and Zephyr.

See Changelog for the complete list of changes.

Release tag 

The release tag for the nRF Connect SDK manifest repository (https://github.com/nrfconnect/sdk-nrf) is v2.6.1. Check the west.yml file for the corresponding tags in the project repositories.

To use this release, check out the tag in the manifest repository and run west update. See Get the nRF Connect SDK code and Updating the repositories for more information.

For information on the included repositories and revisions, see Repositories and revisions for v2.6.1.

IDE and tool support 

nRF Connect extension for Visual Studio Code is the recommended IDE for nRF Connect SDK v2.6.1. See the Installation section for more information about supported operating systems and toolchain.

Supported modem firmware 

See Modem firmware compatibility matrix for an overview of which modem firmware versions have been tested with this version of the nRF Connect SDK.

Use the latest version of the nRF Programmer app of nRF Connect for Desktop to update the modem firmware. See Updating the modem firmware for instructions.

Known issues 

Known issues are only tracked for the latest official release. See known issues for nRF Connect SDK v2.6.1 for the list of issues valid for the latest release.

Changelog 

The following sections provide detailed lists of changes by component.

Protocols 

This section provides detailed lists of changes by protocol.

Matter

Updated:
- The default Message Reliability Protocol (MRP) retry intervals for Thread devices to two seconds to reduce the number of spurious retransmissions in Thread networks.
- Increased the number of available packet buffers in the Matter stack to avoid packet allocation issues.

Wi-Fi

Added:
- Build-time disconnection timeout configuration.
- BSSID as a parameter for the Wi-Fi connect command.
- Auto-security mode with a fresh key management type to enhance connection time.
- The following fixes and improvements:
  - Wi-Fi stuck in an awake state.
  - Frequent Wi-Fi disconnections in a congested environment and low RSSI.
  - HTTPS upload and download performance issues.
  - MQTT disconnection in a congested environment and low RSSI.
  - Selecting the best RSSI access point.
  - Rate adaptation enhancements to improve range in the 2.4 GHz band.
  - Radio test - Error in setting reg_domain.

To accommodate all fixes and improvements, there is a 1 kB increase in the stack usage of the WPA supplicant. Users must increase the stack sizes appropriately in their applications.

Thread

Fixed otPlatCryptoPbkdf2GenerateKey API implementation to allow a fallback to legacy Mbed TLS implementation instead of returning OT_ERROR_NOT_CAPABLE.

Applications 

This section provides detailed lists of changes by application.

Matter Bridge

Added:
- The CONFIG_BRIDGE_BT_MAX_SCANNED_DEVICES Kconfig option to set the maximum number of scanned Bluetooth LE devices.
- The CONFIG_BRIDGE_BT_SCAN_TIMEOUT_MS Kconfig option to set the scan timeout.
Fixed an issue where the recovery mechanism for Bluetooth LE connections might not work correctly.

Samples 

This section provides detailed lists of changes by sample.

Wi-Fi samples

Wi-Fi: Shell sample:
- Modified connect command to provide better control over connection parameters.
- Added Auto-Security-Personal mode to the connect command.

Zephyr 

The Zephyr fork in nRF Connect SDK (sdk-zephyr) contains all commits from the upstream Zephyr repository up to and including 23cf38934c0f68861e403b22bc3dd0ce6efbfa39. It also contains some nRF Connect SDK specific additions and commits cherry-picked from the upstream Zephyr repository, including the following one:

Fixed the GPIO configuration that is used in the pinctrl driver for the QSPI IO3 line. Due to these incorrect settings, the QSPI NOR flash driver could not initialize successfully for a flash chip configured to work in non-Quad (2 I/O) mode.

For a complete list of nRF Connect SDK specific commits and cherry-picked commits since v2.6.0, run the following command:

git log --oneline manifest-rev ^v3.5.99-ncs1

Library name	Version information
Modem library	Changelog
LwM2M carrier library	Changelog