Zigbee SDK Version 9.1.0 - Release Notes (Jun 23, 2026)#

Zigbee Version 9.1.0

Silicon Labs is the vendor of choice for OEMs developing Zigbee networking into their products. The Silicon Labs Zigbee platform is the most integrated, complete, and feature-rich Zigbee solution available.

Silicon Labs EmberZNet SDK contains Silicon Labs’ implementation of the Zigbee stack specification.

Click here for earlier releases.

Release Summary#

Key Features | API Changes | Bug Fixes | Changes | Chip Enablement

Key Features#

• Configurable next RX channel for Green Power Device (GPD) bi-directional commissioning

• Secure inter-PAN message fragmentation with APS link encryption after key establishment

• Packet handoff post-incoming filter with per-packet link quality (RSSI, LQI, channel)

• Zigbee 4.0 gateway sample application

• GCC and IAR toolchain upgrades (GCC 14.2.rel1 and IAR 9.70.4)

• Antenna calibration APIs for networking products

• Configurable route table size in Zigbee Pro Stack Config

API Changes#

• GPD channel request : New API sl_zigbee_gpd_af_plugin_set_next_channel() to set the next and second next RX channels used in GPD Channel Request commissioning frames.

• Inter-PAN : The Inter-PAN plugin supports secure fragmented messages after CBKE, plugin interpan fragment-test CLI adds an optional encryption option for testing purpose.

• Packet handoff : New stack callback sl_zigbee_post_incoming_packet_filter_with_lqi_and_rssi_cb() and type sl_zigbee_packet_link_quality_t for packet handoff.

Bug Fixes#

See Bug Fixes.

Changes#

See Changes.

Chip Enablement#

None

Key Features#

New Features | Enhancements | Removed Features | Deprecated Features

New Features#

Added in 9.1.0#

Zigbee 4.0 gateway sample application#

A new Zigbee 4.0 gateway host sample application is available. It extends the Zigbee 3.0 gateway with support for Zigbee 4.0-style joining and works with the Zigbee 4.0 light and switch sample applications.

Enhancements#

Added in 9.1.0#

Configurable next RX channel for GPD commissioning#

Green Power Device (GPD) applications can set the next RX channel and second next RX channel at runtime before bi-directional commissioning Channel Request GPDFs (previously build-time only; both default to channel 11 if unset). Use node set-next-channel <nextRxChannel> [<secondNextRxChannel>] with the Zigbee GPD CLI component (channels 11–26, before commissioning), or sl_zigbee_gpd_af_plugin_set_next_channel(). See API Changes.

Secure inter-PAN fragmentation#

The Inter-PAN plugin now supports sending and receiving large, APS link-encrypted inter-PAN messages using Inter-PAN Message Fragmentation (IPMF) after Certificate-Based Key Establishment (CBKE) has completed.

• Secure fragmented traffic: Applications can exchange encrypted inter-PAN payloads that exceed a single frame by using fragmentation that follows the extended APS frame control format used for Smart Energy inter-PAN (first fragment and subsequent fragments are identified separately; fragment responses use a distinct format).

• CLI: The plugin interpan fragment-test command accepts an optional options argument. Set bit 0 to enable stub APS link encryption on the test message (requires an established inter-PAN link key and the project option that allows APS-encrypted inter-PAN messages, same as plugin interpan long).

Packet handoff link quality#

Applications that use packet handoff (the Packet Handoff component, zigbee_packet_handoff) can implement a new stack callback that runs after each intercepted incoming packet is processed, in addition to the existing post-incoming filter callback.

The new callback provides radio link quality for the received packet:

• RSSI (received signal strength)

• LQI (link quality indicator)

• Channel (radio channel on which the packet was received)

GCC and IAR toolchain upgrade#

Zigbee SDK 9.1.0 is validated with GCC 14.2.rel1 and IAR Embedded Workbench 9.70.4—the compiler versions delivered with Simplicity SDK 2026.6. IAR 9.70.4 supports Zigbee SoC and NCP applications on Series 3, in addition to Series 2 targets. After you upgrade, rebuild your Zigbee projects in Simplicity Studio so your applications and the included sample apps build with these toolchains.

Configurable route table size#

SL_ZIGBEE_ROUTE_TABLE_SIZE is exposed in the Zigbee Pro Stack Config component configuration header so you can size the route table from Simplicity Studio without editing stack sources manually.

Antenna calibration APIs#

Zigbee stack APIs support antenna calibration workflows for networking products, including follow-up calibration updates in this release.

Removed Features#

None

Deprecated Features#

None

API Changes#

New APIs | Modified APIs | Removed APIs | Deprecated APIs

New APIs#

Added in 9.1.0#

New type sl_zigbee_packet_link_quality_t contains rssi, lqi, and channel fields for use with the callback above.

Modified APIs#

None

Removed APIs#

Removed in 9.1.0#

Build-time GPD next RX channel configuration was removed in favor of sl_zigbee_gpd_af_plugin_set_next_channel() or the node set-next-channel CLI.

Deprecated APIs#

None

Bug Fixes#

The following issues were resolved in Zigbee SDK 9.1.0.

Changes#

The following general changes are included in Zigbee SDK 9.1.0.

Chip Enablement#

None

Application Example Changes#

New Examples | Modified Examples | Removed Examples | Deprecated Examples

New Examples#

Modified Examples#

Standardized display labels and project names for certain Zigbee example applications in Simplicity Studio were updated. Example apps now use a consistent title format that identifies the stack (Zigbee, Zigbee SE, Zigbee GP, or Zigbee BLE DMP), the target role (SoC, Host, or NCP), and the application name with readable spacing. The NCP SPI example was renamed from ncp-spi to zigbee_ncp_spi; NCP example labels were normalized; and GPD single-button/LED variant examples use distinct project names and labels. This affects how examples appear when browsing or creating projects in Studio only. Full details are in Changes (1630265). Application functionality is unchanged.

Removed Examples#

None

Deprecated Examples#

None

Known Issues and Limitations#

Code example for Known Issue 1503910:

 // Set the user repack threshold
                static uint32_t user_repack_threshold = 1024;
                /***************************************************************************//**
                * Perform a user-triggered repack with a configurable threshold.
                *
                * This function sets the number of bytes (threshold) that must remain free
                * before a forced repack is triggered. It performs repack operations until
                * the threshold is satisfied or no further memory can be freed.
                ******************************************************************************/
                void nvm3_repack_with_threshold(void)
                {
                  sl_status_t sta;
                  nvm3_MemInfo_t memInfo;
                  size_t initMemInfo;  // Get available memory
                  if (nvm3_getMemInfo(nvm3_defaultHandle, &memInfo) != SL_STATUS_OK) {
                    printf("Get memory info failed at startup\r\n");
                    return;
                  }  // Set the repack headroom to user threshold
                  nvm3_defaultInit->repackHeadroom = user_repack_threshold;
                  sta = nvm3_open(nvm3_defaultHandle, nvm3_defaultInit);
                  if (sta != SL_STATUS_OK) {
                    printf("NVM3 re-open with increased headroom failed: %lu\r\n", sta);
                    return;
                  }
                  initMemInfo = memInfo.availableMemory;
                  int repack =0;
                  while (user_repack_threshold > memInfo.availableMemory) {
                    repack++;
                    sta = nvm3_repack(nvm3_defaultHandle);
                    if (sta != SL_STATUS_OK) {
                      printf("ERROR: NVM3 repack failed! Status: %lu\r\n", sta);
                      EFM_ASSERT(sta == SL_STATUS_OK);
                      break;
                    }
                    nvm3_getMemInfo(nvm3_defaultHandle, &memInfo);
                  }
                  return;
                } // Set the user repack threshold
                static uint32_t user_repack_threshold = 1024;
                /***************************************************************************//**
                * Perform a user-triggered repack with a configurable threshold.
                *
                * This function sets the number of bytes (threshold) that must remain free
                * before a forced repack is triggered. It performs repack operations until
                * the threshold is satisfied or no further memory can be freed.
                ******************************************************************************/
                void nvm3_repack_with_threshold(void)
                {
                  sl_status_t sta;
                  nvm3_MemInfo_t memInfo;
                  size_t initMemInfo;  // Get available memory
                  if (nvm3_getMemInfo(nvm3_defaultHandle, &memInfo) != SL_STATUS_OK) {
                    printf("Get memory info failed at startup\r\n");
                    return;
                  }  // Set the repack headroom to user threshold
                  nvm3_defaultInit->repackHeadroom = user_repack_threshold;
                  sta = nvm3_open(nvm3_defaultHandle, nvm3_defaultInit);
                  if (sta != SL_STATUS_OK) {
                    printf("NVM3 re-open with increased headroom failed: %lu\r\n", sta);
                    return;
                  }
                  initMemInfo = memInfo.availableMemory;
                  int repack =0;
                  while (user_repack_threshold > memInfo.availableMemory) {
                    repack++;
                    sta = nvm3_repack(nvm3_defaultHandle);
                    if (sta != SL_STATUS_OK) {
                      printf("ERROR: NVM3 repack failed! Status: %lu\r\n", sta);
                      EFM_ASSERT(sta == SL_STATUS_OK);
                      break;
                    }
                    nvm3_getMemInfo(nvm3_defaultHandle, &memInfo);
                  }
                  return;
                }