Bluetooth LE SDK Host Stack Version 11.0.0 - Release Notes (Jan 22, 2026)#

Simplicity SDK Version 2025.12.0

The Bluetooth Host Stack is a Bluetooth 6.1-compliant stack that provides the core functionality along with multiple API to simplify development. The core functionality offers both standalone mode, allowing a developer to create and run their application directly on the SoC, or NCP mode, allowing for the use of an external host MCU.

Click here for earlier releases.

Release Summary#

Key Features | API Changes | Bug Fixes | Chip Enablement

Key Features#

Bluetooth host qualification for Core specification 6.1.
PAwR event counter reporting.
Channel classification reporting for a remote peripheral device.
Support for larger BGAPI payload size in NCP applications with compile-time configurability.

API Changes#

The parameter list of an API function declares as 'void' explicitly if the function has no parameters.
Added parameters for NADM capabilities in commands sl_bt_cs_read_local_supported_capabilities and sl_bt_evt_cs_read_remote_supported_capabilities_complete.

Bug Fixes#

Improved L2CAP and ATT packet validation and error handling.

Chip Enablement#

None.

Key Features#

New Features | Enhancements | Removed Features | Deprecated Features

New Features#

The Bluetooth host stack has been improved and qualified for Core specification 6.1.
Support PAwR event counter reporting with new feature component bluetooth_feature_linklayer_interface.
Support reporting the channel classification of a remote peripheral device.
New component bgapi_service_feature_system provides the System class APIs of the BGAPI Service. Command sl_bgapi_system_get_max_payload_sizes can be used to get the maximum payload sizes that BGAPI Protocol is configured to support in the application.
The static GATT database supports the "Write Without Response" property so that the descriptor value could be updated by remote GATT clients using Write Command.
The dynamic GATT database has a new descriptor property flag SL_BT_GATTDB_DESCRIPTOR_WRITE_NO_RESPONSE so that the descriptor value could be updated by remote GATT clients using Write Command.

Enhancements#

None.

Removed Features#

None.

Deprecated Features#

None.

API Changes#

New APIs | Modified APIs | Removed APIs | Deprecated APIs

New APIs#


New API Signature	Deprecated API replaced by this (if any)
sl_status_t sl_bt_linklayer_event_info_reporting_enable	N/A
sl_bt_evt_linklayer_event_info_report	N/A
sl_bt_evt_connection_channel_classification	N/A

Modified APIs#


Old API	Modified
sl_status_t sl_bt_dfu_flash_upload_finish()	sl_status_t sl_bt_dfu_flash_upload_finish(void)
sl_status_t sl_bt_system_hello()	sl_status_t sl_bt_system_hello(void)
sl_status_t sl_bt_system_start_bluetooth()	sl_status_t sl_bt_system_start_bluetooth(void)
sl_status_t sl_bt_system_stop_bluetooth()	sl_status_t sl_bt_system_stop_bluetooth(void)
sl_status_t sl_bt_system_forcefully_stop_bluetooth()	sl_status_t sl_bt_system_forcefully_stop_bluetooth(void)
sl_status_t sl_bt_system_reboot()	sl_status_t sl_bt_system_reboot(void)
sl_status_t sl_bt_system_data_buffer_clear()	sl_status_t sl_bt_system_data_buffer_clear(void)
sl_status_t sl_bt_resource_disable_connection_tx_report()	sl_status_t sl_bt_resource_disable_connection_tx_report(void)
sl_status_t sl_bt_scanner_stop()	sl_status_t sl_bt_scanner_stop(void)
sl_status_t sl_bt_nvm_erase_all()	sl_status_t sl_bt_nvm_erase_all(void)
sl_status_t sl_bt_test_dtm_end()	sl_status_t sl_bt_test_dtm_end(void)
sl_status_t sl_bt_sm_set_debug_mode()	sl_status_t sl_bt_sm_set_debug_mode(void)
sl_status_t sl_bt_sm_delete_bondings()	sl_status_t sl_bt_sm_delete_bondings(void)
sl_status_t sl_bt_resolving_list_remove_all_devices()	sl_status_t sl_bt_resolving_list_remove_all_devices(void)
sl_status_t sl_bt_accept_list_remove_all_devices()	sl_status_t sl_bt_accept_list_remove_all_devices(void)
sl_status_t sl_bt_cs_read_local_supported_capabilities	sl_status_t sl_bt_cs_read_local_supported_capabilities: added new return parameters nadm_sounding_capability and nadm_random_capability
sl_bt_evt_cs_read_remote_supported_capabilities_complete	sl_bt_evt_cs_read_remote_supported_capabilities_complete: added new fields nadm_sounding_capability and nadm_random_capability
sl_status_t sl_bt_cs_test_end()	sl_status_t sl_bt_cs_test_end(void)
sl_status_t sl_bt_cte_transmitter_clear_dtm_parameters()	sl_status_t sl_bt_cte_transmitter_clear_dtm_parameters(void)
sl_status_t sl_bt_cte_receiver_clear_dtm_parameters()	sl_status_t sl_bt_cte_receiver_clear_dtm_parameters(void)
sl_status_t sl_bt_cte_receiver_disable_silabs_cte()	sl_status_t sl_bt_cte_receiver_disable_silabs_cte(void)
sl_status_t sl_bt_user_reset_to_dfu()	sl_status_t sl_bt_user_reset_to_dfu(void)

Removed APIs#


Removed API Name	Was Deprecated?
void sl_bt_system_reset	Yes
sl_status_t sl_bt_sm_set_bonding_key	Yes

Deprecated APIs#

None.

Bug Fixes#

ID	Issue Description	GitHub / Salesforce Reference (if any)	Affected Software Variants, Hardware, Modes, Host Interfaces
1521108	In ATT_EXECUTE_WRITE_REQ handling, the GATT server now ensures either all prepared write requests are successfully written in the GATT database or nothing will be written. Previously, successful writes before an error would remain in the database, leaving it in an inconsistent state.	None	All; generic software issue
1521428	Improved the L2CAP CoC signaling packet validation by adding the length checks for all L2CAP command types and checking both L2CAP header length and SDU length.	None	All; generic software issue
1564484	Fixed an issue where the device could enter EM2 even when the LF clock accuracy was below the threshold required for reliable Bluetooth connections.	None	All; generic software issue

Impact of Release Changes#

Impact Statements and Migrations from 10.x to 11.0.0#

Change	Migration Guide	Affected Software Variants if applicable	Affected Modes	Affected OPNs / Boards / OPN Combinations	Affected Host Interfaces
The parameter list of an API function declared as 'void' explicitly if the function has no parameters	Code that correctly calls with no arguments will continue to work. If there happens to be code calling such functions with arguments, remove the arguments.	All	All	Hardware agnostic	N/A
New parameters nadm_sounding_capability and nadm_random_capability in commands sl_bt_cs_read_local_supported_capabilities	The implementation that invokes this API should provide valid pointers for the new parameters, or provide NULL if the capability values are unused.	All	All	Hardware agnostic	N/A
New data fields nadm_sounding_capability and nadm_random_capability in event sl_bt_evt_cs_read_remote_supported_capabilities_complete	Rebuild NCP host applications on Simplicity SDK 2025.12.	All	NCP	Hardware agnostic	N/A

Known Issues and Limitations#

ID	Issue or Limitation Description	GitHub / Salesforce Reference (if any)	Workaround (if any)	Affected Software Variants, Hardware, Modes, Host Interfaces
1417141	The OTA DFU fast mode in the Bootloader with Apploader is unreliable due to the chance of packet losses.	None	Use OTA DFU reliable mode.	All
1562916	The device does not enter EM2 when Bluetooth is used on radio boards brd2704a, brd4319a and brd4337a due to LFRCO precision mode is not enabled by default.	None	Enable LFRCO precision mode by overriding configuration SL_CLOCK_MANAGER_LFRCO_PRECISION to cmuPrecisionHigh in the application project.	All