SDK upgrade guide
Gecko SDK 4.4 to Simplicity SDK 2025.6: what needs attention
Migratorisk's knowledge base lists 198 documented changes between Gecko SDK 4.4 and Simplicity SDK 2025.6 across 3 releases. 94 of them are rated likely to break code, configuration or builds that use them. Below is each change, what a scan also reviews on this path, and how to see which ones apply to your project.
Find which of these affect your firmware
Migratorisk scans your project on your own computer and reports only the changes your code, configuration and build actually touch. Your source code is not uploaded.
python -m pip install migratorisk migratorisk scan --project ./your-firmware --from simplicity-sdk-4.4.0 --to simplicity-sdk-2025.6.0 --out report.html
Requires Python 3.12 or newer. Results are free and complete without sign-up; sharing a report with us is optional.
Set up the local scanOr answer a few questions insteadWhere the changes are
What changes between Gecko SDK 4.4 and Simplicity SDK 2025.6
Ordered by impact. Each item names the release that introduced it and links to the official source. A change only matters if your project uses what changed; the scan checks that.
EmberZNet 8 renames the public Zigbee API
Simplicity SDK 2024.6 ships EmberZNet 8.0, which renames Zigbee public APIs and enumerations (ember*/emberAf* to sl_zigbee_*/sl_zigbee_af_*) and moves status codes from the 1-byte EmberStatus to the 4-byte sl_status_t. Silicon Labs' own upgrade script flags this for manual work: application source is not converted automatically.
Zigbee (EmberZNet): functions renamed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 renames these functions: EMBER_PAGE_CHANNEL_MASK_FROM_CHANNEL_MASK -> SL_ZIGBEE_PAGE_CHANNEL_MASK_FROM_CHANNEL_MASK, EMBER_PAGE_CHANNEL_MASK_FROM_CHANNEL_NUMBER -> SL_ZIGBEE_PAGE_CHANNEL_MASK_FROM_CHANNEL_NUMBER, EMBER_TEST_ASSERT -> SL_ZIGBEE_TEST_ASSERT, emberActiveEndpointsRequest -> sl_zigbee_active_endpoints_request, emberAddChild -> sl_zigbee_add_child… Code using the old names no longer compiles. Covers 2,613 names.
Zigbee (EmberZNet): constants renamed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 renames these constants: EMBER_ACCEPT_PACKET -> SL_ZIGBEE_ACCEPT_PACKET, EMBER_ACCEPT_PACKET_OVERRIDE_SECURITY -> SL_ZIGBEE_ACCEPT_PACKET_OVERRIDE_SECURITY, EMBER_ACCEPT_PACKET_SKIP_NWK_CRYPTO -> SL_ZIGBEE_ACCEPT_PACKET_SKIP_NWK_CRYPTO, EMBER_ACTIVE_SCAN -> SL_ZIGBEE_ACTIVE_SCAN, EMBER_ACTIVE_SCAN_DURATION -> SL_ZIGBEE_ACTIVE_SCAN_DURATION… Code using the old names no longer compiles. Covers 1,334 names.
Zigbee (EmberZNet): constants removed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 no longer declares these constants from Gecko SDK 4.4.6: ATTRIBUTE_MAX_DATA_SIZE, EMBER_ADC_CONVERSION_BUSY, EMBER_ADC_CONVERSION_DEFERRED, EMBER_ADC_CONVERSION_DONE, EMBER_ADC_NO_CONVERSION_PENDING, EMBER_ADDRESS_TABLE_ENTRY_IS_ACTIVE… Code using them fails to compile or link. Covers 698 names.
Zigbee (EmberZNet): functions removed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 no longer declares these functions from Gecko SDK 4.4.6: API_TRACE_PROXY_BROADCAST, appendEmberApsFrame, appendEmberBeaconClassificationParams, appendEmberBeaconData, appendEmberBeaconIterator, appendEmberBindingTableEntry… Code using them fails to compile or link. Covers 421 names.
Zigbee (EmberZNet): types renamed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 renames these types: EmberAesMmoHashContext -> sl_zigbee_aes_mmo_hash_context_t, EmberAfAllowedInterPanMessage -> sl_zigbee_af_allowed_inter_pan_message_t, EmberAfAllowedInterpanOptions -> sl_zigbee_af_allowed_interpan_options_t, EmberAfAppLinkKeyRequestPolicy -> sl_zigbee_af_app_link_key_request_policy_t, EmberAfApplicationTask -> sl_zigbee_af_application_task_t… Code using the old names no longer compiles. Covers 355 names.
Platform services: headers removed in Simplicity SDK 2024.6.0
These headers exist in Gecko SDK 4.4.6 and are gone in Simplicity SDK 2024.6.0: auth.h, bootloader-common.h, bootloader-interface-app.h, bootloader-interface-standalone.h, bootloader-interface.h, can_bus.h, can_bus_priv.h, canopen_cfg.h… Code that includes them stops compiling. Covers 274 names.
RAIL radio: functions removed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 no longer declares these functions from Gecko SDK 4.4.6: RAILCb_BLE_HadmGdCompTableLoad, RAIL_BLE_ConfigHadm, RAIL_BLE_ConfigHadmAntenna, RAIL_BLE_ConfigPhy1MbpsHadm, RAIL_BLE_ConfigPhy2MbpsHadm, RAIL_BLE_EnableHadm… Code using them fails to compile or link. Covers 255 names.
Platform services: constants renamed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 renames these constants: EMBER_FAMILY_BGM1 -> SL_ZIGBEE_FAMILY_BGM1, EMBER_FAMILY_BGM13 -> SL_ZIGBEE_FAMILY_BGM13, EMBER_FAMILY_BGM21 -> SL_ZIGBEE_FAMILY_BGM21, EMBER_FAMILY_EFR32BG12P -> SL_ZIGBEE_FAMILY_EFR32BG12P, EMBER_FAMILY_EFR32BG13P -> SL_ZIGBEE_FAMILY_EFR32BG13P… Code using the old names no longer compiles. Covers 122 names.
Bluetooth LE: constants removed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 no longer declares these constants from Gecko SDK 4.4.6: ABR_CS_PARSER_INVALID_RSSI_VALUE, ABR_CS_PARSER_INVALID_TIME_VALUE, ABR_CS_PARSER_TONE_QUALITY_MASK_LOW, ABR_DEVICE_INITIATOR, ABR_DEVICE_REFLECTOR, ABR_DISCOVERY_STATE_CONN… Code using them fails to compile or link. Covers 121 names.
Platform services: constants removed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 no longer declares these constants from Gecko SDK 4.4.6: CANOPEN_CORE_TASK_PRIO_DFLT, ECC_FAULT, FS_MEDIA_POLL_TASK_PRIO_DFLT, HTTP_CLIENT_TASK_PRIO_DFLT, IO_SD_ASYNC_TASK_PRIO_DFLT, IO_SD_CORE_TASK_PRIO_DFLT… Code using them fails to compile or link. Covers 101 names.
Bluetooth LE: functions removed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 no longer declares these functions from Gecko SDK 4.4.6: abr_cs_event_buf_clear, abr_cs_event_buf_find, abr_cs_event_buf_get_element_for_write, abr_cs_event_buf_get_free_space, abr_cs_event_buf_get_next_element, abr_cs_event_buf_get_next_unindicated… Code using them fails to compile or link. Covers 99 names.
Zigbee (EmberZNet): types removed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 no longer declares these types from Gecko SDK 4.4.6: CallbackTableEntry, DmpUiDeviceType_t, DmpUiLightDirection_t, DmpUiZigBeeNetworkState_t, EInterpanFragmentationStatus, EmberAfDeviceManagementCIN… Code using them fails to compile or link. Covers 85 names.
Platform services: components removed from Simplicity SDK 2024.6.0
These SLC components are removed from Simplicity SDK 2024.6.0: cslib_acmp_series_0, cslib_acmp_series_1, cslib_csen_series_0, cslib_csen_series_1, generic_series_provider, gsdk_version… A project that lists them no longer generates. Covers 83 names.
Bluetooth LE: functions removed in Simplicity SDK 2024.12.0
Simplicity SDK 2024.12.0 no longer declares these functions from Simplicity SDK 2024.6.0: ble_peer_manager_peripheral_set_advertiser, cs_initiator_display_print_value, cs_initiator_get_procedure, cs_initiator_identify, cs_initiator_set_default_config, cs_initiator_step… Code using them fails to compile or link. Covers 57 names.
Zigbee (EmberZNet): functions removed in Simplicity SDK 2024.12.0
Simplicity SDK 2024.12.0 no longer declares these functions from Simplicity SDK 2024.6.0: append_sl_zigbee_multiprotocol_priorities_t, fetch_sl_zigbee_multiprotocol_priorities_t, keyword_detected, keyword_detection_init, keyword_detection_process_action, sl_mac_find_child_short_id… Code using them fails to compile or link. Covers 55 names.
Bluetooth LE: constants removed in Simplicity SDK 2024.12.0
Simplicity SDK 2024.12.0 no longer declares these constants from Simplicity SDK 2024.6.0: BLE_PEER_MANAGER_ON_BOOT, CS_DISCOVERY_STATE_CONN, CS_DISCOVERY_STATE_FINISHED, CS_DISCOVERY_STATE_IDLE, CS_DISCOVERY_STATE_SCAN, CS_ERROR_EVENT_CS_PROCEDURE_RESTART_FAILED… Code using them fails to compile or link. Covers 54 names.
Security: headers removed in Simplicity SDK 2024.6.0
These headers exist in Gecko SDK 4.4.6 and are gone in Simplicity SDK 2024.6.0: ba411e_config.h, ba413_config.h, ba414ep_config.h, ba431_config.h, compiler_extentions.h, crypto_management.h, cryptolib_def.h, cryptolib_types.h… Code that includes them stops compiling. Covers 29 names.
Bluetooth LE: functions removed in Simplicity SDK 2025.6.0
Simplicity SDK 2025.6.0 no longer declares these functions from Simplicity SDK 2024.12.0: cs_initiator_display_print_float_value, cs_initiator_display_set_bit_error_rate, cs_initiator_display_set_distance, cs_initiator_display_set_distance_progress, cs_initiator_display_set_likeliness, cs_initiator_display_set_rssi_distance… Code using them fails to compile or link. Covers 28 names.
RAIL radio: types removed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 no longer declares these types from Gecko SDK 4.4.6: EmberIncomingMacMessage, EmberMacAddress, EmberMacAddressMode, EmberMacFrame, EmberMessageLength, EmberMessageOptions… Code using them fails to compile or link. Covers 28 names.
Bluetooth LE: types removed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 no longer declares these types from Gecko SDK 4.4.6: abr_antenna_offset_t, abr_cs_parser_configuration_t, abr_cs_parser_meas_data_handle_t, abr_cs_parser_meas_data_t, abr_discovery_state_t, abr_initiator_config_t… Code using them fails to compile or link. Covers 27 names.
Platform services: functions removed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 no longer declares these functions from Gecko SDK 4.4.6: IO_SERIAL_CTRLR_REG, SERIAL_SPI_BUS_MODE_CPHA_GET, SERIAL_SPI_BUS_MODE_CPOL_GET, Serial_ConfigureHandleQty, Serial_ConfigureMemSeg, Serial_CtrlrReqAlignGet… Code using them fails to compile or link. Covers 26 names.
Bluetooth LE: constants removed in Simplicity SDK 2025.6.0
Simplicity SDK 2025.6.0 no longer declares these constants from Simplicity SDK 2024.12.0: BG_VERSION_BUILD, BG_VERSION_HASH, BG_VERSION_MAJOR, BG_VERSION_MINOR, BG_VERSION_PATCH, CS_EVENT_BUF_DATA_MAX_LEN… Code using them fails to compile or link. Covers 25 names.
Peripheral drivers: headers removed in Simplicity SDK 2024.6.0
These headers exist in Gecko SDK 4.4.6 and are gone in Simplicity SDK 2024.6.0: dmactrl.h, em_adc.h, em_aes.h, em_aes_compat.h, em_can.h, em_cryotimer.h, em_csen.h, em_dac.h… Code that includes them stops compiling. Covers 24 names.
Peripheral drivers: functions removed in Simplicity SDK 2025.6.0
Simplicity SDK 2025.6.0 no longer declares these functions from Simplicity SDK 2024.12.0: CORE_DECLARE_NVIC_MASK, CORE_DECLARE_NVIC_ZEROMASK, CORE_ENTER_NVIC, CORE_EXIT_NVIC, CORE_EnterNvicMask, CORE_GetNvicEnabledMask… Code using them fails to compile or link. Covers 23 names.
Platform services: constants removed in Simplicity SDK 2024.12.0
Simplicity SDK 2024.12.0 no longer declares these constants from Simplicity SDK 2024.6.0: GPIO_PORT_A_PIN_COUNT, GPIO_PORT_A_PIN_MASK, GPIO_PORT_B_PIN_COUNT, GPIO_PORT_B_PIN_MASK, GPIO_PORT_C_PIN_COUNT, GPIO_PORT_C_PIN_MASK… Code using them fails to compile or link. Covers 22 names.
Bluetooth LE: components removed from Simplicity SDK 2024.6.0
These SLC components are removed from Simplicity SDK 2024.6.0: abr_ans, abr_cs_parser, abr_initiator, abr_ras, abr_reflector, apploader_lib… A project that lists them no longer generates. Covers 18 names.
Peripheral drivers: components removed from Simplicity SDK 2024.6.0
These SLC components are removed from Simplicity SDK 2024.6.0: emlib_adc, emlib_aes, emlib_can, emlib_cryotimer, emlib_crypto, emlib_csen… A project that lists them no longer generates. Covers 18 names.
Bluetooth LE: headers removed in Simplicity SDK 2024.6.0
These headers exist in Gecko SDK 4.4.6 and are gone in Simplicity SDK 2024.6.0: abr_ans.h, abr_cs_parser.h, abr_cs_parser_types.h, abr_file_log.h, abr_file_log_config.h, abr_initiator.h, abr_initiator_config.h, abr_initiator_interface.h… Code that includes them stops compiling. Covers 17 names.
Zigbee (EmberZNet): constants removed in Simplicity SDK 2024.12.0
Simplicity SDK 2024.12.0 no longer declares these constants from Simplicity SDK 2024.6.0: SL_ZIGBEE_AF_PLUGIN_DMP_TUNING_BLE_ADVERTISEMENT_PRIORITY_MAX, SL_ZIGBEE_AF_PLUGIN_DMP_TUNING_BLE_ADVERTISEMENT_PRIORITY_MIN, SL_ZIGBEE_AF_PLUGIN_DMP_TUNING_BLE_CONNECTION_INIT_PRIORITY_MAX, SL_ZIGBEE_AF_PLUGIN_DMP_TUNING_BLE_CONNECTION_INIT_PRIORITY_MIN, SL_ZIGBEE_AF_PLUGIN_DMP_TUNING_BLE_CONNECTION_PRIORITY_MAX, SL_ZIGBEE_AF_PLUGIN_DMP_TUNING_BLE_CONNECTION_PRIORITY_MIN… Code using them fails to compile or link. Covers 15 names.
RAIL radio: functions removed in Simplicity SDK 2025.6.0
Simplicity SDK 2025.6.0 no longer declares these functions from Simplicity SDK 2024.12.0: RAIL_LoadUserSeqApp, RAIL_ShutdownUserSeqApp, RAIL_USER_GetMboxMsg, RAIL_USER_InitCp, RAIL_USER_InitSemaphore, RAIL_USER_ReleaseSemaphore… Code using them fails to compile or link. Covers 14 names.
SDK: components removed from Simplicity SDK 2024.12.0
These SLC components are removed from Simplicity SDK 2024.12.0: ot_rtos_wrapers_stub, ot_rtos_wrappers_real, sl_flex_assert, sl_wisun_ns_list, wisun_test_certificates, zw_appshw_doorlockkeypad… A project that lists them no longer generates. Covers 13 names.
Zigbee (EmberZNet): functions removed in Simplicity SDK 2025.6.0
Simplicity SDK 2025.6.0 no longer declares these functions from Simplicity SDK 2024.12.0: sl_zigbee_, sl_zigbee_af_incoming_packet_filter_cb, sl_zigbee_af_outgoing_packet_filter_cb, sl_zigbee_af_set_t_c_link_key_update_timer_milli_seconds, sl_zigbee_direct_calculate_admin_key, sl_zigbee_direct_calculate_basic_key… Code using them fails to compile or link. Covers 13 names.
Peripheral drivers: functions removed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 no longer declares these functions from Gecko SDK 4.4.6: SE_debugLockApply, SE_debugLockStatus, SE_debugSecureDisable, SE_debugSecureEnable, SE_deviceErase, SE_deviceEraseDisable… Code using them fails to compile or link. Covers 12 names.
Application utilities: constants removed in Simplicity SDK 2025.6.0
Simplicity SDK 2025.6.0 no longer declares these constants from Simplicity SDK 2024.12.0: APPLY_DEBUG_LOCK, GET_HOST_UPGRADE_STATUS, POST_APPLY_DEBUG_LOCK, POST_HOST_UPGRADE_STATUS, POST_VALIDATE_HOST_IMAGE, READ_VSE_VERSION… Code using them fails to compile or link. Covers 10 names.
Bluetooth LE: types removed in Simplicity SDK 2024.12.0
Simplicity SDK 2024.12.0 no longer declares these types from Simplicity SDK 2024.6.0: cs_discovery_state_t, cs_initiator_mode_t, cs_phy_t, sl_bt_cbap_central_state_t, sl_bt_cbap_peripheral_state_t, sl_bt_cbap_role_t… Code using them fails to compile or link. Covers 10 names.
Zigbee (EmberZNet): headers removed in Simplicity SDK 2024.6.0
These headers exist in Gecko SDK 4.4.6 and are gone in Simplicity SDK 2024.6.0: byte-utilities.h, ember-alternate-mac.h, ember-debug.h, ember-duty-cycle.h, ember-multi-network.h, ember-random-api.h, ember-types.h, ember.h… Code that includes them stops compiling. Covers 10 names.
Application utilities: headers removed in Simplicity SDK 2024.12.0
These headers exist in Simplicity SDK 2024.6.0 and are gone in Simplicity SDK 2024.12.0: accelerometer.h, audio_classifier.h, constants.h, magic_wand.h, model_profiler.h, predictor.h, recognize_commands.h, timestamp.h… Code that includes them stops compiling. Covers 9 names.
Application utilities: headers removed in Simplicity SDK 2024.6.0
These headers exist in Gecko SDK 4.4.6 and are gone in Simplicity SDK 2024.6.0: app_webpage.h, app_wifi_commissioning.h, app_wifi_events.h, dhcp_client.h, dhcp_server.h, ethernetif.h, httpfsdata.h, lwipopts.h… Code that includes them stops compiling. Covers 9 names.
Bluetooth LE: headers removed in Simplicity SDK 2024.12.0
These headers exist in Simplicity SDK 2024.6.0 and are gone in Simplicity SDK 2024.12.0: cs_initiator_configurator.h, hci_reset.h, sl_bt_cbap_lib.h, sl_sensor_hall.h, sl_sensor_imu.h, sl_sensor_pressure.h, sl_sensor_sound.h, sl_simple_com.h… Code that includes them stops compiling. Covers 9 names.
Platform services: functions removed in Simplicity SDK 2024.12.0
Simplicity SDK 2024.12.0 no longer declares these functions from Simplicity SDK 2024.6.0: SL_GPIO_PORT_IS_VALID, SL_GPIO_PORT_PIN_IS_VALID, halButtonPinState, halClearLed, halSetLed, halStackRadioPowerDownBoard… Code using them fails to compile or link. Covers 9 names.
Bluetooth LE: components removed from Simplicity SDK 2024.12.0
These SLC components are removed from Simplicity SDK 2024.12.0: bluetooth_host_adaptation_libraries_release, bt_rail_compatibility_fix, cbap_lib, sensor_hall, sensor_imu, sensor_pressure… A project that lists them no longer generates. Covers 8 names.
Bluetooth Mesh: constants removed in Simplicity SDK 2025.6.0
Simplicity SDK 2025.6.0 no longer declares these constants from Simplicity SDK 2024.12.0: sl_btmesh_cmd_prov_test_identity_id, sl_btmesh_cmd_test_set_adv_scan_params_id, sl_btmesh_cmd_test_set_sar_config_id, sl_btmesh_cmd_test_set_segment_send_delay_id, sl_btmesh_rsp_prov_test_identity_id, sl_btmesh_rsp_test_set_adv_scan_params_id… Code using them fails to compile or link. Covers 8 names.
SDK: components removed from Simplicity SDK 2024.6.0
These SLC components are removed from Simplicity SDK 2024.6.0: ot_lower_mac_spinel, ot_stack_tcp_stubs, sl_flex_rail_sleep, wisun_cli, wisun_legacy_socket_wrapper, zpal_zwave_nvm_instance… A project that lists them no longer generates. Covers 8 names.
SDK: components removed from Simplicity SDK 2025.6.0
These SLC components are removed from Simplicity SDK 2025.6.0: zw_debug_print, zw_production, zw_zniffer_dependency, zw_zpal_production, zw_zpal_zniffer, zw_zpal_zniffer_app… A project that lists them no longer generates. Covers 8 names.
Bluetooth LE: components removed from Simplicity SDK 2025.6.0
These SLC components are removed from Simplicity SDK 2025.6.0: bluetooth_common_release, bt_fp_ncp_default, bt_fp_soc_client, bt_fp_soc_default, bt_fp_soc_server, cs_ras… A project that lists them no longer generates. Covers 7 names.
Bluetooth Mesh: functions removed in Simplicity SDK 2024.12.0
Simplicity SDK 2024.12.0 no longer declares these functions from Simplicity SDK 2024.6.0: sl_btmesh_sensor_people_count_get_cadence, sl_btmesh_sensor_people_count_handle_cadence, sl_btmesh_sensor_people_count_set_cadence, sl_btmesh_sensor_thermometer_cadence_init, sl_btmesh_sensor_thermometer_get_cadence, sl_btmesh_sensor_thermometer_handle_cadence… Code using them fails to compile or link. Covers 7 names.
Platform services: constants removed in Simplicity SDK 2025.6.0
Simplicity SDK 2025.6.0 no longer declares these constants from Simplicity SDK 2024.12.0: NUM_OF_FLASH_PAGES, NVM3KEY_MFG_TOKEN_RANGE_ID, SL_POWER_MANAGER_EVENT_TRANSITION_ENTERING_EM3, SL_POWER_MANAGER_EVENT_TRANSITION_LEAVING_EM3, USERDATA_END, USER_DATA_SIZE. Code using them fails to compile or link. Covers 6 names.
Zigbee (EmberZNet): components removed from Simplicity SDK 2024.6.0
These SLC components are removed from Simplicity SDK 2024.6.0: zigbee_app_framework_common, zigbee_pro_router_stack_basic, zigbee_pro_router_stack_rail_mux, zigbee_pro_router_stack_rail_mux_library, zigbee_pro_stack_basic, zigbee_smart_energy_token_optimization. A project that lists them no longer generates. Covers 6 names.
RAIL radio: components removed from Simplicity SDK 2024.6.0
These SLC components are removed from Simplicity SDK 2024.6.0: rail_util_hadm_antenna_offset, rail_util_hadm_antenna_offset_wired, rail_util_hadm_antenna_offset_wireless, rail_util_hadm_gdcomp, wfx_bus_sdio. A project that lists them no longer generates. Covers 5 names.
RAIL radio: functions renamed in Simplicity SDK 2024.6.0
Simplicity SDK 2024.6.0 renames these functions: emberAfPluginCommandCoulombCounterGetAdditiveModesBitfield -> sl_zigbee_af_command_coulomb_counter_get_additive_modes_bitfield, emberAfPluginCommandCoulombCounterGetCurrentCoreMode -> sl_zigbee_af_command_coulomb_counter_get_current_core_mode, emberAfPluginCommandCoulombCounterGetEnergyUsage -> sl_zigbee_af_command_coulomb_counter_get_energy_usage, emberAfPluginCommandCoulombCounterResetEnergyUsage -> sl_zigbee_af_command_coulomb_counter_reset_energy_usage, emberAfPluginCoulombCounterTick -> sl_zigbee_af_coulomb_counter_tick. Code using the old names no longer compiles. Covers 5 names.
Zigbee (EmberZNet): constants removed in Simplicity SDK 2025.6.0
Simplicity SDK 2025.6.0 no longer declares these constants from Simplicity SDK 2024.12.0: GP_ARGS, GP_PARAMS, GP_UNUSED_ARGS, SL_ZIGBEE_AF_PLUGIN_NETWORK_STEERING_STATE_VERIFY_TCLK, SL_ZIGBEE_ZIGBEE_PACKET_TYPE_INTERPAN. Code using them fails to compile or link. Covers 5 names.
Bluetooth LE: headers removed in Simplicity SDK 2025.6.0
These headers exist in Simplicity SDK 2024.12.0 and are gone in Simplicity SDK 2025.6.0: cs_ras.h, cs_reflector_event_buf.h, sl_btctrl_hci_reset.h, sl_gatt_service_gas.h. Code that includes them stops compiling. Covers 4 names.
Bluetooth LE: types removed in Simplicity SDK 2025.6.0
Simplicity SDK 2025.6.0 no longer declares these types from Simplicity SDK 2024.12.0: cs_event_data_t, cs_result_t, cs_tx_power_t, ras_opcode_t. Code using them fails to compile or link. Covers 4 names.
Bluetooth Mesh: functions removed in Simplicity SDK 2025.6.0
Simplicity SDK 2025.6.0 no longer declares these functions from Simplicity SDK 2024.12.0: sl_btmesh_prov_test_identity, sl_btmesh_test_set_adv_scan_params, sl_btmesh_test_set_sar_config, sl_btmesh_test_set_segment_send_delay. Code using them fails to compile or link. Covers 4 names.
EZSP host and NCP firmware must move together
EmberZNet 8.0 changes the EZSP protocol version used between a host application and a Zigbee NCP. A host built on the old SDK cannot talk to an NCP built on the new one (and vice versa). Covers 4 names.
Platform services: headers removed in Simplicity SDK 2025.6.0
These headers exist in Simplicity SDK 2024.12.0 and are gone in Simplicity SDK 2025.6.0: sl_device_init_nvic.h, sl_memory.h, sl_memory_region.h, sl_ram_interrupt_vector_init.h. Code that includes them stops compiling. Covers 4 names.
RAIL radio: headers removed in Simplicity SDK 2024.6.0
These headers exist in Gecko SDK 4.4.6 and are gone in Simplicity SDK 2024.6.0: sl_rail_util_eff.h, sl_rail_util_hadm_antenna_offset.h, sl_rail_util_hadm_gdcomp_tables.h, sl_rail_util_pa_dbm_powersetting_mapping_table_eff.h. Code that includes them stops compiling. Covers 4 names.
RAIL radio: types removed in Simplicity SDK 2025.6.0
Simplicity SDK 2025.6.0 no longer declares these types from Simplicity SDK 2024.12.0: RAIL_SeqUserAppInfo_t, RAIL_UserCommonGlobal_t, RAIL_UserCpReq_t, UserSeqShMem_t. Code using them fails to compile or link. Covers 4 names.
Zigbee (EmberZNet): headers removed in Simplicity SDK 2024.12.0
These headers exist in Simplicity SDK 2024.6.0 and are gone in Simplicity SDK 2024.12.0: dmp-tuning-profiles.h, dmp-tuning.h, keyword_detection.h, pro_compliance_stack_interface.h. Code that includes them stops compiling. Covers 4 names.
And 138 more changes, all checked by the scan.
What a scan of this path also reviews
Beyond the documented changes, Migratorisk reviews these upgrade risks for Silicon Labs SDK projects on this path. Each one is reported only when the project shows the trigger.
Series 0 and Series 1 devices are not supported by Simplicity SDK
When it applies: The project targets a Series 0 or Series 1 device, and the selected path moves from Gecko SDK to Simplicity SDK.
Why it matters: From Simplicity SDK 2024.6.0, Series 0 and Series 1 devices are no longer supported; Silicon Labs' own upgrade check marks this upgrade as impossible. Gecko SDK 4.4/4.5 LTS is the supported line for these parts.
What to do: Stay on Gecko SDK 4.4/4.5 LTS for this hardware, or plan a hardware move to a Series 2 part (pin, RF and certification impact) before moving to Simplicity SDK.
Zigbee host and NCP must be upgraded together
When it applies: The project is a Zigbee host application that talks to an NCP over EZSP.
Why it matters: EZSP versions change between SDK releases; a host only talks to an NCP built with a compatible stack.
What to do: Upgrade host and NCP firmware as one release, and make sure the host can still reflash an NCP that runs the old firmware.
Field updates must still be accepted by the bootloader on deployed devices
When it applies: The application updates itself in the field (OTA DFU, AppLoader, Zigbee OTA or Mesh DFU) through the Gecko Bootloader already on each device.
Why it matters: The move to Simplicity SDK changes stacks and platform code, usually growing the image; the new application must still fit the download slot of the bootloader on deployed devices and use the same signing keys.
What to do: Keep the GBL signing and encryption keys, the storage slot layout and the application start address; check the new image size against the download slot; rehearse an update from the production firmware and bootloader.
Updating the Gecko Bootloader itself
When it applies: The repository builds a Gecko Bootloader with the SDK.
Why it matters: A new bootloader must keep the storage layout, keys and application interface of the one on deployed devices, and it can only be replaced in the field if the bootloader upgrade path was planned.
What to do: Decide whether deployed devices keep their current bootloader (usual) or receive a bootloader upgrade; if so, test the upgrade image on production devices before release.
The project must be upgraded and regenerated with SLC
When it applies: Silicon Labs projects are generated from the .slcp by SLC (Simplicity Studio or slc-cli).
Why it matters: Moving from Gecko SDK to Simplicity SDK changes the SDK id in the .slcp and renames or removes many components, configuration options and APIs (EmberZNet 8 renames the whole Zigbee API). Silicon Labs' upgrade handles component changes, not application source.
What to do: Run the project upgrade (Simplicity Studio's Upgrade, or slc upgrade) on a clean branch, regenerate, then review the diff of config/ and the .slcp before touching application code. Never keep hand edits in autogen/.
Stored data must survive the update
When it applies: The firmware keeps data in NVM3 or tokens (network keys, bonding data, Mesh provisioning, application settings).
Why it matters: Stack and token handling change between Gecko SDK and Simplicity SDK; network keys, bonding data and provisioning written by the old firmware must survive the update.
What to do: Update a device that has real stored data (joined network, bonded phone, provisioned node) from the production firmware and check it keeps working without re-pairing or re-commissioning.
SDK extensions must move to versions built for the target SDK
When it applies: The project uses SDK extensions (for example Matter, WiSeConnect or AI/ML) on top of the Silicon Labs SDK.
Why it matters: Each extension release is built and tested against one SDK release. Mixing versions fails to generate or builds an untested combination.
What to do: Pick the extension release that names the target SDK in its release notes and upgrade it together with the SDK.
A copy of the SDK lives inside the project
When it applies: The project contains a copied Gecko or Simplicity SDK folder instead of linking to an installed SDK.
Why it matters: An upgrade does not touch the copy. Local patches to it are easily lost or silently kept, and the build may mix old and new SDK files.
What to do: List local changes to the copied SDK (diff it against the matching release), then replace the copy with the target SDK and re-apply only the changes still needed.
Device series could not be confirmed for the move to Simplicity SDK
When it applies: The .slcp lists no device part number, so the scan cannot tell whether the hardware is Series 1 or Series 2.
Why it matters: Simplicity SDK supports only Series 2 and Series 3 devices; a Series 0/1 product cannot make this move at all.
What to do: Check the part number on the board (or the device component Simplicity Studio shows for the project) before planning the upgrade.
Check the Secure Engine firmware required by the target SDK
When it applies: The project targets a Series 2 device, whose Secure Engine runs its own firmware.
Why it matters: Newer SDKs are released with a matching Secure Engine firmware version; security features and some PSA Crypto behaviour depend on it, and devices in the field keep the SE firmware they shipped with unless it is updated.
What to do: Compare the SE firmware version on production devices with the one in the target SDK's platform release notes, and decide whether the update must include an SE firmware upgrade.
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Related upgrade paths
- Gecko SDK 4.4 to Simplicity SDK 2024.6
- Gecko SDK 4.2 to Gecko SDK 4.4
- Simplicity SDK 2024.12 to Simplicity SDK 2025.6
- Simplicity SDK 2025.6 to Simplicity SDK 2025.12
- Simplicity SDK 2025.6 to Simplicity SDK 2026.6
Generated from the rule catalog of Migratorisk 0.3.0. This is an automated summary of published SDK changes, not a review of your project, and it does not replace builds and device tests. How the scanner is validated.