WiSeConnect - Multiprotocol Version 4.0.1 (Mar 25, 2026) - Release Notes#
Wi-Fi 6 + BLE (WiSeConnect) SDK Version 4.0.1
Simplicity SDK Version 2025.12.2
The Multiprotocol Software Development Kit (SDK) provides Wi-Fi and BLE coexistence and packet traffic arbitration (PTA) features.
Click here for earlier releases.
Release Summary#
Key Features | API Changes | Bug Fixes | Chip Enablement
Key Features#
Added in 4.0.1#
None
Added in 4.0.0#
None
API Changes#
Added in 4.0.1#
None
Added in 4.0.0#
None
Bug Fixes#
Fixed in 4.0.1#
Enhanced TCP RX throughput in WLAN+BLE coex mode by optimizing TCP window size. This enables packet aggregation and improves data transfer performance in dual-mode operation, addressing cases where throughput may be limited to approximately 12 Mbps in WLAN+BLE connected mode (BLE as Central)
Fixed an issue where WLAN releasing the radio during an active AP pause could cause the background scan to remain paused indefinitely, by re‑triggering the AP pause when WLAN reacquires the radio so scanning can resume correctly
Fixed in 4.0.0#
Fixed multiple issues where the SiWx917 encountered socket/SSL failures, hangs, MQTT data stoppage, BLE disconnections, and instability. These issues occurred during Wi-Fi reconnect loops, MQTT cycling, BLE scanning/advertising, and stress scenarios with up to 10 BLE connections.
Resolved long-duration test failures including errors 0x4E08 and -13; Pixel DLE interoperability issues; connection-parameter update hangs; and instances where the device became unresponsive under continuous Wi-Fi, MQTT, and GATT notification load.
Fixed an issue where the
ble_get_local_addressAPI became unresponsive when invoked after a specific sequence involving Wi-Fi initialization, scan, and connection; followed by BLE advertising and scanning start/stop operations; and a subsequent Wi-Fi disconnect.
Chip Enablement#
Added in 4.0.1#
None
Added in 4.0.0#
None
Key Features#
New Features | Enhancements | Removed Features | Deprecated Features
Note: See Feature Matrix for a list of any applicable APIs, examples, software variants, modes, hardware, and host interfaces applicable for each feature.
New Features#
Added in 4.0.1#
None
Added in 4.0.0#
None
Enhancements#
Added in 4.0.1#
Added 120 MHz clock support in WLAN+BLE coex mode. This improves SSL TX/RX throughput in WLAN+BLE connected mode
Added in 4.0.0#
None
Removed Features#
Removed in 4.0.1#
None
Removed in 4.0.0#
None
Deprecated Features#
Deprecated in 4.0.1#
None
Deprecated in 4.0.0#
None
API Changes#
New APIs | Modified APIs | Removed APIs | Deprecated APIs
New APIs#
Added in 4.0.1#
None
Added in 4.0.0#
None
Modified APIs#
Modified in 4.0.1#
None
Modified in 4.0.0#
None
Removed APIs#
Removed in 4.0.1#
None
Removed in 4.0.0#
None
Deprecated APIs#
Deprecated in 4.0.1#
None
Deprecated in 4.0.0#
None
Bug Fixes#
Note: See the Feature Matrix section for a list of all hardware parts that work with the WiSeConnect SDK.
Fixed in 4.0.1#
| ID | Issue Description | GitHub / Salesforce Reference (if any) | Affected Software Variants, Hardware, Modes, Host Interfaces |
|---|---|---|---|
| 1575580 | Enhanced TCP RX throughput in WLAN+BLE coex mode by optimizing TCP window size. This enables packet aggregation and improves data transfer performance in dual-mode operation, addressing cases where throughput may be limited to approximately 12 Mbps in WLAN+BLE connected mode (BLE as Central). | None |
|
| 1504573 | Fixed an issue where WLAN releasing the radio during an active AP pause could cause the background scan to remain paused indefinitely, by re‑triggering the AP pause when WLAN reacquires the radio so scanning can resume correctly. | None |
|
Fixed in 4.0.0#
| ID | Issue Description | GitHub / Salesforce Reference (if any) | Affected Software Variants, Hardware, Modes, Host Interfaces |
|---|---|---|---|
| 1521233 | Fixed an issue where the DUT became non-connectable after the second remote central auto-disconnect (~40 min) when operating with 8 BLE peripheral connections and 2 BLE central connections performing active data transmission/reception, along with continuous MQTT connect/disconnect operations running in a loop. | None |
|
| 1511407 | Fixed a command disallowed (0x4E0C) error occurring when stopping BLE advertising in the SoftAP+BLE provisioning application after remote client disconnect and reconnect. Also resolved web interface unresponsiveness that occurred during subsequent connection attempts. | None |
|
| 1505752 | Fixed an issue where socket connections failed during SSL transmission when BLE scanning and advertising were active concurrently in power-save mode with encrypted firmware. | None |
|
| 1453288 | Resolved connectivity instability under high-stress conditions involving Wi-Fi MQTT cycling and simultaneous GATT notifications from 10 BLE connections when using encrypted firmware. | None |
|
| 1276739 | Fixed device hangs when continuous WLAN connect/disconnect and HTTPS GET/deinit operations occur alongside a BLE LE Secure connection. | None |
|
| 1521722 | Fixed an issue where MQTT data transfer stopped after approximately 30 minutes, followed by BLE disconnections after about 1 hour and 30 minutes. | None |
|
| 1515995 | Fixed hang issue during MQTT data transfer with 10 concurrent BLE bidirectional data transfers (TX/RX with notifications) when one peripheral connection was a Pixel device with DLE enabled. | None |
|
| 1505989 | Fixed a connection timeout error (0x4E08) observed on the remote central device during long-duration testing involving MQTT data transfer and 10 concurrent BLE connections performing bidirectional data transfers | None |
|
| 1397267 | Fixed an issue where MQTT connections occasionally failed with error code -13 when provisioning via a OnePlus 7T mobile device. | None |
|
| 1471402 |
Fixed an issue where the ble_get_local_address API became unresponsive when invoked after a specific sequence of Wi-Fi and BLE operations, including: Wi-Fi and BLE initialization, an initial ble_get_local_address call, Wi-Fi scan and connection, BLE advertising start/stop, BLE scanning start/stop, Wi-Fi disconnect, ble_get_state, and a subsequent ble_get_local_address call.
|
None |
|
| 1443334 | Fixed an issue where the SiWx917 could become unresponsive and experience disconnections from both Wi-Fi and BLE under heavy-load conditions involving continuous Wi-Fi activity, MQTT traffic, and GATT notifications from 10 BLE connections. | None |
|
Chip Enablement#
Added in 4.0.1#
None
Added in 4.0.0#
None
Application Example Changes#
New Examples | Modified Examples | Removed Examples | Deprecated Examples
Note: See the Feature Matrix section for a list of all hardware parts that work with the WiSeConnect SDK.
New Examples#
Added in 4.0.1#
None
Added in 4.0.0#
None
Modified Examples#
Modified in 4.0.1#
| Example Name | Changes | Supported Software Variants if applicable | Supported Modes | Supported OPNs / Boards / OPN Combinations | Supported Host Interfaces |
|---|---|---|---|---|---|
|
WLAN-BLE Unified Coex App
README |
Fixed logic in async_socket_select() for more reliable socket operations.Removed redundant semaphore release and duplicate callback state assignment. Improved status checking before processing socket data. Enhanced callback state management for AWS MQTT select handling. |
Standard and Lite |
|
|
SPI, UART |
Modified in 4.0.0#
| Example Name | Changes | Supported Software Variants if applicable | Supported Modes | Supported OPNs / Boards / OPN Combinations | Supported Host Interfaces |
|---|---|---|---|---|---|
|
Wi-Fi Client BLE Throughput App |
Added continuous throughput support for TCP RX and UDP RX traffic in the Wi-Fi Station BLE Throughput application.
See README |
Standard and Lite |
|
|
SPI, UART |
Removed Examples#
Removed in 4.0.1#
None
Removed in 4.0.0#
None
Deprecated Examples#
Deprecated in 4.0.1#
None
Deprecated in 4.0.0#
None
Known Issues and Limitations#
Added in 4.0.1#
| ID | Issue or Limitation Description | GitHub / Salesforce Reference (if any) | Workaround (if any) | Affected Software Variants, Hardware, Modes, Host Interfaces |
|---|---|---|---|---|
| NA | In AP + BLE mode, usage is restricted to Wi-Fi provisioning only; at any given time, only a single protocol connection is permitted, meaning that a connection can be established with either the SiWx917's Wi-Fi SoftAP or its BLE interface, but not both simultaneously. Additionally, third-party BLE connections are not supported if a third-party STA is connected to the 917 Wi-Fi SoftAP, and likewise, third-party STA connections are not supported if a third-party BLE device is already connected to the 917 BLE interface. | None | None |
|
Added in 4.0.0#
| ID | Issue or Limitation Description | GitHub / Salesforce Reference (if any) | Workaround (if any) | Affected Software Variants, Hardware, Modes, Host Interfaces |
|---|---|---|---|---|
| 1455876 | MQTT publish failure (error code -7) occurs for QoS 0 messages after 30 minutes when running 10 concurrent BLE connections and GATT notifications without SMP on an encrypted connectivity (network processor) firmware image. | None | None |
|
| 1451820 |
SiWx917 fails to re-connect after a few MQTT disconnections during a BLE scan start and stop loop with the wlan_ble_unified_coex_app_soc example application.
|
None | None |
|
| 1479757 | A bus thread looping issue was observed while running a multi-socket application. | None | None |
|
| 1444697 | BLE disconnections occur when loading or clearing the TLS certificate. | None | None |
|
| 1512574 | When the DUT is configured to advertise with BLE SMP enabled and a continuous WLAN scan is active, the remote BLE central device may frequently fail to pair and occasionally fail to connect. | None | None |
|
| N/A | In co-existence mode, configuring 480 KB of RAM for the network processor and 192 KB for the application processor can reduce Wi-Fi throughput by approximately 10 Mbps due to limited memory available for data packets. | None | None |
|
| N/A | Multiprotocol operation (Wi-Fi station + BLE) with EAP security modes is supported only for memory configurations EXT_FEAT_416K_M4SS_256K (416 KB network processor + 256 KB application processor) and EXT_FEAT_480K_M4SS_192K (480 KB network processor + 192 KB application processor). | None | None |
|
| N/A | System-level changes introduced to enhance stability have resulted in some increase in power numbers (up to 15% for smaller connection intervals of 200 ms) for BLE-connected only cases for modules. Impact is smaller for longer connection intervals. | None | None |
|
| 1557787 | The Wi-Fi station returns error 0x1FF9C (SL_STATUS_SI91X_DHCP_HANDSHAKE_FAILURE) in congested environments when operating in concurrent mode with both NAT and PAT features enabled. | None | None |
|
| 1574418 |
Using slc generate --toolchain gcc or slc generate --with toolchain_gcc may fail with exclusivity errors due to the wiseconnect_toolchain_gcc_standard component incorrectly providing toolchain_gcc, resulting in a conflict with the Simplicity SDK toolchain_gcc component. If using those two command line options results in exclusivity errors, then you can remove them. Note that in a future WiseConnect release, you might have to reintroduce the toolchain option on the command line. Refer to future WiseConnect release notes for updates on possible behavior changes.
|
None | None |
|