Gecko Platform Release Notes - Version 5.1.3 GA
Simplicity SDK Suite 2024.12.3
August 6, 2025
The Gecko Platform provides infrastructure support for applications developed with higher-level protocols and an interface with the underlying hardware. It comprises several modules:
- CMSIS Device: Vendor-independent hardware abstraction layer for Cortex® M processors.
- Peripherals: Complete peripheral API for Silicon Labs EFM32, EZR32, and EFR32 MCUs and SoCs.
- Drivers: Gecko Platform driver library for on-chip peripherals, typically DMA-based and utilizing low-energy features.
- Services: Common services like NVM3 and Power Manager.
- CPC (Co-Processor Communication): Library for inter-processor communication via a serial link, used in NCP and RCP solutions.
- Common components: Used across SDKs.
- Middleware: Includes Capacitive Sensing Firmware Library and GLIB graphics library.
- Security: Includes mbed TLS and other security services.
- Operating System: Includes Micrium OS Kernel and CMSIS-RTOS2 layer.
- Gecko Bootloader: Configurable library for generating bootloaders for various Silicon Labs protocol stacks, compatible with EFM32 and EFR32 Series 2 and later devices.
- MVP Math Library: Real and Complex Matrix and Vector operations using the Matrix Vector Processor on EFR32xG24, an alternative to CMSIS-DSP.
- Examples: Illustrative applications demonstrating platform functionality.
- Boards and External Devices: Covers supported hardware.
- Other Gecko Platform Components: Includes changes to documentation, project building, configuration, and other aspects.
- RAIL (Radio Abstraction Interface Layer): Customizable radio interface layer supporting proprietary or standards-based wireless protocols, managed through stack libraries or directly via the Flex SDK.
These release notes cover SDK version(s):
- Platform 5.1.3 released August 6, 2025
- Platform 5.1.2 released April 1, 2025
- Platform 5.1.1 released February 5, 2025
- Platform 5.1.0 released December 16, 2024
KEY FEATURES
CMSIS Device
- Added support for new EFR32xG27 OPN, EFR32xG26 OPN's (MGM260PB22VNA2, MGM260PB32VNA2, MGM260PB32VNN2).
CPC
- Fixed a potential security vulnerability.
Security
- Mbed TLS upgraded to latest version 3.6.2.
Boards and External Devices
- Added support for board OPN's BRD2709A, BRD2711A, BRD4350A, BRD4351A, BRD4412A, BRD4413A.
RAIL 5.1.0
- Added support for Bluetooth Low Energy (BLE) Channel Sounding (CS) on the EFR32xG24, enabling accurate distance measurement.
- Added support for concurrent listening feature on the EFR32xG26 part.
- Added support for 1 Mbps and 2 Mbps custom 802.15.4 SUN PHYs on the EFR32xG26 part.
Contents
- 1 New Items
- 2 CMSIS Device
- 3 Peripherals
- 4 Drivers
- 5 Services
- 6 CPC
- 7 Common
- 8 Middleware
- 9 Security
- 10 Operating System
- 11 Gecko Bootloader
- 12 MVP Math Library
- 13 Examples
- 14 Boards and External Devices
- 15 Other Gecko Platform Software Components
- 16 RAIL Library
1 New Items
None.
2 CMSIS Device
2.1 New Items
Added in release 5.1.1
Added support for the following OPN families:
- EFR32BG22L
- EFR32BG24L
Added support for the following module OPN's:
- BGM260PB22VNA2
- BGM260PB32VNA2
- MGM260PB32VNA5
- MGM260PB32VNN5
- MGM260PB22VNA5
- MGM260PD32VNA2
- MGM260PD32VNN2
- MGM260PD22VNA2
Added in release 5.1.0
- Added EFR32xG27 OPN: EFR32BG27C320F768IJ39.
- Added support for the following module OPN's: MGM260PB22VNA2, MGM260PB32VNA2, MGM260PB32VNN2.
- Added the following EFR32xG26 OPNs: EFR32MG26B211F3200IM48, EFR32MG26B221F3200IM48, EFR32MG26B211F2048IM68, EFR32MG26B221F2048IM68, EFM32PG26B301F2048IM68, EFM32PG26B101F512IM68, EFM32PG26B301F1024IM68, EFR32MG26B311F3200IL136, EFM32PG26B301F2048IL136, EFM32PG26B101F512IL136, EFM32PG26B301F1024IL136, EFR32BG26B311F2048IM48, EFR32BG26B321F2048IM48, EFR32BG26B311F2048IM68, EFR32BG26B321F2048IM68, EFR32BG26B311F2048IL136, EFR32BG26B311F1024IM68, EFR32BG26B321F1024IM68, EFR32BG26B311F1024IL136, EFR32MG26B411F3200IM48, EFR32MG26B421F3200IM48, EFR32MG26B511F3200IM48, EFR32MG26B521F3200IM48, EFR32MG26B411F3200IM68, EFR32MG26B421F3200IM68, EFR32MG26B511F3200IM68, EFR32MG26B521F3200IM68, EFR32MG26B511F3200IL136, EFR32BG26B511F3200IM48, EFR32BG26B511F3200IM68, EFR32BG26B511F3200IL136, EFM32PG26B501F3200IM68, EFM32PG26B501F3200IL136, EFM32PG26B501F3200IM48, EFM32PG26B500F3200IM48, EFR32BG26B411F3200IM48, EFR32BG26B421F3200IM48, EFR32BG26B410F3200IM48, EFR32BG26B420F3200IM48.
2.2 Improvements
Changed in release 5.1.0
None.
2.3 Fixed Issues
Fixed in release 5.1.1
| ID # | Description |
| 1391130 | Changed the license text in some CMSIS headers from MSLA to Zlib. Removed MSLA license text from startup_<family>.c source file. |
Fixed in release 5.1.0
| ID # | Description |
| 1321003 | Fixed missing HFRCO bus clock enable that could lead to bus faults in SystemHFRCODPLLClockGet() and SystemHFRCOEM23ClockGet(). |
2.4 Known Issues in the Current Release
None.
2.5 Deprecated Items
Deprecated in release 5.1.0
None.
2.6 Removed Items
Removed in release 5.1.0
GCC and IAR specific assembly startup files have been removed. The C startup file should be used instead.
3 Peripherals
3.1 New Items
Added in release 5.1.0
None.
3.2 Improvements
Changed in release 5.1.0
- em_acmp: Added the ACMP_OutputGet function to get ACMP output value.
- em_ldma: Removed unnecessary assert in LDMA_Init and LDMA_StartTransfer.
3.3 Fixed Issues
Fixed in release 5.1.3
| ID # | Description |
| 1436872 | em_eusart: Fixed sync initialization to properly respect the init.enable argument instead of always enabling the peripheral. |
Fixed in release 5.1.1
| ID # | Description |
| 1363972 | em_iadc: Added missing input for iadcPosInputVbat and iadcNegInputVbat for EFR32xG27 devices. |
Fixed in release 5.1.0
| ID # | Description |
| 1307127 | em_emu: Fixed a bug in EMU_RamPowerDown() function leading to not covering all RAM shutdown cases for series 2. |
| 1333169 | Fixed rare race-condition where DMADRV could return a transfer count of 0 instead of 1 when interrupts are masked and the channel IF is set. |
| 1337998 | em_ldma: On EFR32XG25 devices, the MATCHEN and MATCHVAL fields in the LDMA descriptors were inverted. Fixed so that the structure properly represents the EFR32XG25 hardware. |
| 1260083 | em_prs: Added missing PRS asynchronous channels in header file for each channel in xG24 and xG26 family. Added missing channels definition in em_prs.h. |
| 1344396 | Added missing headers: peripheral_dcdc_coulomb_counter.h, peripheral_dcdc_coulomb_counter_compat.h, peripheral_etampdet.h, peripheral_etampdet_compat, peripheral_keyscan.h, peripheral_keyscan_compat.h, peripheral_sysrtc.h and peripheral_sysrtc_compat.h. |
| 1357932 | em_emu: Fixed default EM0/1 default peak current for EFR32xG27 Boost parts. Corrected from emuDcdcBoostEM01PeakCurrent_Load25mA to emuDcdcBoostEM01PeakCurrent_Load23mA. |
| 1286382 | em_rmu: Fix compiler warnings for analyzer-null-dereference. em_bus: Fix compiler warnings for analyzer-shift-count-overflow. |
3.4 Known Issues in the Current Release
None.
3.5 Deprecated Items
Deprecated in release 5.1.0
None.
3.6 Removed Items
Removed in release 5.1.0
- em_dbg: Removed DBG_DisableDebugAccess() as it was not available for Series 2 devices.
4 Drivers
4.1 New Items
Added in release 5.1.0
None.
4.2 Improvements
Changed in release 5.1.0
None.
4.3 Fixed Issues
Fixed in release 5.1.0
| ID # | Description |
| 1361482 | UARTDRV: Fixed a bug in UARTDRV_Abort() where the callback function was called passing a NULL pointer instead of a pointer to the data buffer. |
| 1284781 | UARTDRV: Fixed issues in UARTDRV_Abort() leading to incorrect number of EM1 requirements. Fixed handling of enableRxWhensleeping. |
| 1332867 | DMADRV: Fixed a rare issue where DMADRV_TransferRemainingCount could return 0 when the DMA had a single byte to transfer. This happened on systems with high IRQ latency, or that called the API in an atomic/critical section. |
| 1290690 | Spidrv: Fixed issue of wrong order of operations for Series 2 devices, which leads to incorrect pin configuration initialization, by enabling routing after configuring pins in SPIDRV_Init function. |
| 1321680 | Spidrv: Fixed issue of SPIDRV instantiation using USART on EFR32XG25 despite the absence of USART on these platforms. |
| 1173169 | NVM3 optimization for cache search is added, which can be enabled using configuration NVM3_OPTIMIZATION. |
4.4 Known Issues in the Current Release
None.
4.5 Deprecated Items
Deprecated in release 5.1.0
None.
4.6 Removed Items
Removed in release 5.1.0
None.
5 Services
5.1 New Items
Added in release 5.1.1
- Clock Manager: Added component clock_manager_oscillator_calibration_override to override default oscillator calibration values with values from NVM3. Currently supports HFXO. New APIs allow reading, writing, and deleting HFXO override calibration from NVM.
- NVM3: NVM3 secure writes and reads are enabled by default for Series-3 devices. Migration from earlier versions requires erasing the NVM3 region for Series-3 devices.
Added in release 5.1.0
- Clock Manager: Added AUTO option to enable HFXO and use it as the default high frequency clock when radio is used (RAIL library present).
- Clock Manager: Added support for CLKINO to Clock Manager. CLKINO added to SYSCLK, DPLL, and EM01GRPBCLK clock branches as a reference option. A SL_CLOCK_MANAGER_CLKINO_FREQ configuration and pintool annotation were added to configure a GPIO for external clock input.
5.2 Improvements
Changed in release 5.1.1
- Clock manager: Added an option to enable or disable the use of CTUNE from Manufacturing tokens/User Data page for LFXO and HFXO.
Changed in release 5.1.0
- Sleeptimer: Changed type of overflow_counter variable to prevent overflow when the peripheral is clocked by a high frequency clock.
- Clock Manager: The default value of SL_CLOCK_MANAGER_PCLK_DIVIDER is now 1 on Series 2 devices to align with the default value in device_init.
5.3 Fixed Issues
Fixed in release 5.1.3
| ID # | Description |
| 1455259 | Clock Manager: Fixed incorrect default HFRCO value of 80 MHz for EFR32BG22C112, which should be limited to 38.4 MHz. |
| 1486589 | Clock Manager: Fixed default Peripheral Clock (PCLK) divider for Series 2 devices. New default is 2. A divider of one could exceed PCLK maximum frequency if HCLK > 40 MHz, leading to incorrect peripheral behavior. |
| 1449985 | Memory Manager: Fixed sl_memory_get_heap_high_watermark() returning incorrect value (0xFFFFFFF8) after multiple memory allocation/deallocation cycles. |
| 1481652 | Common Token Manager: Removed condition if (nvm3Key != 0) that skipped writing dynamic tokens to NVM3 key '0'. |
Fixed in release 5.1.2
| ID # | Description |
| 1385086 | HFXO Manager: IRQ priority reduced to CORE_ATOMIC_BASE_PRIORITY_LEVEL to avoid affecting time-critical customer code using higher priority levels. |
| 1425220 | Memory Manager: Fix an slc generation issue with the memory manager redirect component on si917 devices. |
| 1421163 | Fixed link time warnings in the MicriumOS CMSIS-RTOS layer by reworking code implementation, eliminating false positive warnings that occurred only when Link Time Optimization (LTO) was activated. |
Fixed in release 5.1.0
| ID # | Description |
| 1308159 | Memory manager: Fix bug in realloc algorithm ensuring metadata of free blocks is updated correctly. Avoids running out of memory when using realloc() when memory is available. Fixes issues related to reservations by considering reservation offsets in alloc, free, realloc, reserve, and release blocks. |
| 1181978 | Memory Manager: Fixed an issue where SLI_BLOCK_LEN_BYTE_TO_DWORD() would sometimes return the wrong number of words. Allocations made with an alignment not a multiple of 4 could, in a rare scenario, overlap each other. |
| 1346413 | Memory Manager: Fixed heap corruption in sl_memory_realloc() when reducing an allocated block. |
| 1354963 | Memory manager: Fixed issue related to statistic feature. Heap high watermark was overflowing. Ensures heap high watermark is always accurate. |
| 1323169 | Memory Manager: Added a missing closure of critical section within sl_memory_free() in an early exit path. Prevents infinite atomic section if sl_memory_free() is called twice with the same block. |
| 1324463 | sl_mpu: Fixed a bug where the first bytes of the .data section would still be marked as executable after calling sl_mpu_disable_execute_from_ram(). Fix properly aligns the end of the ramfunc section (must be 32 bytes aligned if MPU is used). |
| 1251562 | HFXO Manager: Fixed a corner case where HFXO startup time measurement could be started with a wrong start measurement, leading to a bad value. Corrected the root cause of an assertion failure in sl_hfxo_manager.c. |
| 1305241 | Fixed FreeRTOS Power Manager/Sleeptimer integration code where the number of elapsed OS ticks during sleep was not evaluated properly, leading to unnecessary creation of sleeptimers with very small timeout values. |
| 1336345 | Power manager: Fixed an issue where removing a requirement that was not added previously would lead to an assertion failure. |
| 1336702 | Power Manager: Fixed an issue where interrupts could be delayed until the next interrupt cycle due to a missing ISB instruction in the critical section of the power manager. |
| 1290210 | Power manager: Fixed issue of sl_power_manager_init not enabling GPIO bus clock. Added sl_clock_manager_enable_bus_clock(SL_BUS_CLOCK_GPIO) function in sl_power_manager_init() to initialize the GPIO bus clock. |
| 1289318 | Sleep Timer: Defined module name for the Power Manager debug feature to correctly display the requirement set by the sleep timer. |
| 1336478 | Sleep Timer: Fixed an issue where the callback would be incorrectly called when the callback execution time exceeded the period of a periodic timer. |
| 1356508 | Clock Manager: Fixed issue where invalid LFXO and HFXO CTune MFG tokens caused clock_manager_init to attempt to initialize LFXO and HFXO improperly on Series 2. |
| 1351026 | Clock Manager: Fixed an issue leading to an unused variable warning related to rfpll configuration. |
| 1356859 | Clock Manager: Added missing VDAC1 clock initialization for EFR32xG24 and EFR32xG26 devices. |
| 1312889 | Clock Manager: Fixed a reference to cmuClock_LCDCLK undeclared for the EFR32SG23B020F512IM40 device, leading to a compilation error. |
| 1272260 | Updated documentation to make it easier for customers to update the iostream handles for CLI. |
5.4 Known Issues in the Current Release
None.
5.5 Deprecated Items
Deprecated in release 5.1.0
- The sl_ram_interrupt_vector_init component is deprecated. Interrupt Manager should be used instead.
5.6 Removed Items
Removed in release 5.1.0
None.
6 CPC
6.1 New Items
Added in release 4.6.0
- Introduced experimental support for NETLINK-SDIO on the SiWx917m platform.
6.2 Improvements
Changed in release 4.6.3
- Enforced minimum RX buffer count at compile-time for UART driver without flow control.
Changed in release 4.6.0
- Increased the maximum supported SPI USART bitrate.
- Addressed minor static code analysis issues.
- Enhanced CPCd error handling for invalid packets.
- Refined CPCd error messages.
6.3 Fixed Issues
Fixed in release 4.6.3
| ID # | Description |
| 1458366 | Corrected cpc secondary version mismatch; updated to version 4.6.3. |
| 1457838 | Fixed incorrect SL_CPC_STATE_ERROR_FAULT report at boot due to unhandled cpc_query_exchange failure in libcpc. |
| 1435171 | CPCd now defaults the SPI bitrate to 1 MHz when unspecified. |
| 1399223 | Fixed issue in cpcd where applications with "reset on disconnect" (e.g., Wi-SUN RCP) caused it to enter an assert loop if stopped during restart. |
Fixed in release 4.6.2
| ID # | Description |
| 1421163 | The sample app CPC Secondary on Micrium OS no longer generates warnings at link time when LTO (Link Time Optimization) is enabled. |
Fixed in release 4.6.1
| ID # | Description |
| 1329252 | A security issue has been identified and fixed in the SPI interface, preventing a data leak vulnerability. |
| 1355407 | Fixed the CPC version reported and displayed by CPCd. |
Fixed in release 4.6.0
| ID # | Description |
| 1378389 | Resolved an issue in CPC Journal where the ID and timestamp were displayed incorrectly. |
| 1355407 | Fixed an issue where some Linux SPI drivers would skip over a transfer of 0 bytes. This caused CPCd and secondary to lose synchronization. |
| 1319502 | Resolved an issue with the CPCd binary included in the OpenWRT asset. |
| 1307636 | Fixed a rare race condition in the SPI driver on systems with high interrupt latency which could lead to CPC system losing communication with the host. |
6.4 Known Issues in the Current Release
- The sample app 'CPC Secondary on Micrium OS' generates warnings at link time when LTO (Link Time Optimization) is enabled.
- CPCd NETLINK-SDIO is stable on Linux kernel v4.x but may experience stability issues on Linux kernel v6.x.
6.5 Deprecated Items
Deprecated in release 4.6.0
None.
6.6 Removed Items
Removed in release 5.1.0
None.
7 Common
7.1 New Items
Added in release 5.1.0
- Event System: Added features to unregister and free a publisher context.
- Event System: Added a feature to unsubscribe from events from a given event class.
- Event System: New sl_event API 'sl_event_queue_delete()', which safely deletes the queue and unsubscribes from all events.
- Event System: Added feature (sl_event_publish_static) for publishing events using a pre-allocated event structure.
7.2 Improvements
Changed in release 5.1.0
- Event System: Improved error handling when pushing events onto subscriber queues. Publishing an event to a subscriber queue is not considered an error from the publisher's perspective.
7.3 Fixed Issues
Fixed in release 5.1.1
| ID # | Description |
| 1383487 | Fixed the CMSE option for CMake support with IAR compiler. Replaced specific CMSE toolchain options with a generic compiler option. |
| 1345860 | Pin Tool: Fixed an issue where SPI signals were not displayed in the pin tool UI. |
Fixed in release 5.1.0
| ID # | Description |
| 1379854 | Event System: Added a missing memory_manager dependency to the slcc component, which could lead to compilation errors. |
| 1351448 | Modified the GNU linker template to move the .noinit section after the .bss section. This fixes the problem where the bootloader's .bss section overlaps with the application's .noinit section, initializing variables that should not be initialized. |
7.4 Known Issues in the Current Release
None.
7.5 Deprecated Items
Deprecated in release 5.1.0
None.
7.6 Removed Items
Removed in release 5.1.0
None.
8 Middleware
8.1 New Items
Added in release 5.1.0
None.
8.2 Improvements
Changed in release 5.1.0
None.
8.3 Fixed Issues
Fixed in release 5.1.0
None.
8.4 Known Issues in the Current Release
None.
8.5 Deprecated Items
Deprecated in release 5.1.0
None.
8.6 Removed Items
Removed in release 5.1.0
None.
9 Security
9.1 New Items
Added in release 5.1.0
- Upgrade to Mbed TLS version 3.6.2 (latest LTS branch, supported until at least March 2027). Release Notes: https://github.com/Mbed-TLS/mbedtls/releases.
- Add SLC component to support Deterministic ECDSA using the PSA Crypto API. User documentation: https://arm-software.github.io/psa-api/crypto/1.1/api/ops/sign.html.
9.2 Improvements
Changed in release 5.1.0
- Upgraded Legacy Deterministic ECDSA component using legacy Mbed TLS API to production quality. PSA Crypto component is recommended as legacy APIs will be obsoleted in Mbed TLS 4.0.
- Added call to SE Manager initialization function sl_se_init in sl_system_init. Applications calling sl_system_init no longer need to call sl_se_init explicitly.
- Added support for calling SE Manager APIs from critical sections. Avoid calling SE Manager from critical sections is recommended.
9.3 Fixed Issues
Fixed in release 5.1.3
| ID # | Description |
| 1475172 | Fixed an issue in sli_sxsymcrypt_lock_cryptomaster_selection which may lead to a thread returning from the function with clock disabled by another interleaving thread. Affected device: SIXX301. |
Fixed in release 5.1.2
| ID # | Description |
| 1403803 | PSA Crypto APIs psa_aead_finish and psa_aead_verify can fail and return PSA_ERROR_HARDWARE_FAILURE on HSE devices when output_size (size_t 32bits) is larger than 255 bytes. Fixed by checking output_size before calling SE Manager functions. If SL_STATUS_INVALID_PARAMETER is returned, PSA SE AEAD driver functions now return PSA_ERROR_INVALID_ARGUMENT instead of PSA_ERROR_HARDWARE_FAILURE. Affected use cases: PSA Crypto multipart AEAD on HSE devices calling psa_aead_finish and psa_aead_verify with output_size > 255 bytes. Affected SDK versions: up to 5.1.1 (inclusive). |
| 1399683 | Fixed an issue in the psa_crypto_aead sample app that manifested when adding plaintext sizes not a multiple of the AES block size (16 bytes). Fragmentation logic failed to update the input buffer pointer when calling psa_aead_update with different input/output lengths. Affected devices: all xG2x devices. Affected SDK versions: up to 5.1.1 (inclusive). |
Fixed in release 5.1.1
| ID # | Description |
| 1284341 | Addressed a security issue in Mbed TLS prior to version 3.6.0 by adding config option SL_MBEDTLS_PSA_ASSUME_EXCLUSIVE_BUFFERS. This option allows users to configure MBEDTLS_PSA_ASSUME_EXCLUSIVE_BUFFERS. Default value is 0 (security by default). Enable by setting to 1. Affected devices: All devices and SDK versions with TrustZone support up to 5.1.0 (not inclusive). |
| 1392116 | Fixed issue in SE Manager API function sl_se_validate_key which returned SL_STATUS_OK when the storage buffer pointer of the key descriptor was NULL. This caused subsequent calls to SE Manager crypto functions to send SE mailbox commands with address zero in a DMA descriptor, causing a BUS ERROR. The fix checks and returns SL_STATUS_INVALID_PARAMETER if the buffer pointer is NULL. Affected devices: all xG2x HSE devices. Affected SDKs: all versions since 3.0.0. |
Fixed in release 5.1.0
| ID # | Description |
| 1363898 | Fixed the Mbed TLS ALT plugin for mbedtls_ecdsa_verify, which allowed signature components (r and s) to be negative. Affected devices: All xG2x device families. Affected SDK versions: All. |
| 1361396 | Fixed a build error in function sli_cryptoacc_driver_single_shot_pbkdf2, called by PSA Crypto API function sl_psa_key_derivation_single_shot, on VSE devices when algorithm PSA_ALG_PBKDF2_AES_CMAC_PRF_128 is selected. Affected device: xG27. Affected SDK versions: 4.4.x (23Q4) and sisdk-2024.6.x. |
| 1354904 | Fixed bug in PSA AEAD drivers which did not check output buffer size before processing context saved data. This may cause buffer overflow. Affected devices: all EFR32xG2x devices (HSE and VSE PSA AEAD drivers). Affected SDK versions: 4.0.0 (21Q4) and later. |
| 1378069 | Fixed bug in PSA AEAD driver for VSE devices, where sli_cryptoacc_transparent_aead_update did not release a mutex before returning when the algorithm is not supported, and the algorithm is CCM with 16 bytes in the last AES block. This causes all PSA VSE drivers to fail in subsequent calls to PSA Crypto APIs accessing CRYPTOACC hardware. Affected devices: xG22 and xG27. Affected SDK versions: 4.0.0 (21Q4) and later. |
9.4 Deprecated Items
Deprecated in release 5.1.0
- All APIs in em_se.h have been deprecated and will be removed in a future release. Functionality has been ported as an internal API under the SE Manager component. Replace all usage of emlib SE with calls to the public SE Manager API.
9.5 Removed Items
Removed in release 5.1.0
None.
10 Operating System
10.1 New Items
Added in release 5.1.0
None.
10.2 Improvements
Changed in release 5.1.0
None.
10.3 Fixed Issues
Fixed in release 5.1.2
| ID # | Description |
| 1414796 | FreeRTOS: Fixed bug where FreeRTOS would override the user provided configuration file with the default one. |
Fixed in release 5.1.0
| ID # | Description |
| 1108940 | Fixed a bug in the Micrium CMSIS RTOS 2 layer where a memory leak would happen when a task would call osThreadTerminate on self. |
10.4 Known Issues in the Current Release
| ID # | Description | Workaround |
| 1166857 | OSTaskQPost doesn't send a message to current task when called with a null pointer as argument. | N/A |
10.5 Deprecated Items
Deprecated in release 5.1.0
None.
10.6 Removed Items
Removed in release 5.1.0
None.
11 Gecko Bootloader
11.1 New Items
Added in release 5.1.0
None.
11.2 Improvements
Changed in release 5.1.0
None.
11.3 Fixed Issues
Fixed in release 5.1.2
| ID # | Description |
| 1379283 | Fixed a logical error in the Bootloader EUART Driver that caused unintended overwriting of configurations in the ROUTEEN register when Hardware Flow Control was enabled. The issue was resolved by correcting the bit configuration logic. |
11.4 Known Issues in the Current Release
None.
11.5 Deprecated Items
Deprecated in release 5.1.0
None.
11.6 Removed Items
Removed in release 5.1.0
None.
12 MVP Math Library
12.1 New Items
Added in release 5.1.0
None.
12.2 Improvements
Changed in release 5.1.0
None.
12.3 Fixed Issues
Fixed in release 5.1.0
None.
12.4 Known Issues in the Current Release
None.
12.5 Deprecated Items
Deprecated in release 5.1.0
None.
12.6 Removed Items
Removed in release 5.1.0
None.
13 Examples
13.1 New Items
Added in release 5.1.1
Added support for the following new LCD sample apps: segment_lcd_ldma, segment_lcd_timer.
Added in release 5.1.0
None.
13.2 Improvements
Changed in release 5.1.0
None.
13.3 Fixed Issues
Fixed in release 5.1.0
None.
13.4 Known Issues in the Current Release
| ID # | Description | Workaround |
| 664803 | Se_manager and psa_crypto sample apps do not work correctly in Simplicity Studio 5's launch console. | In the launch console, change the line terminator selection to None. |
13.5 Deprecated Items
Deprecated in release 5.1.0
None.
13.6 Removed Items
Removed in release 5.1.0
None.
14 Boards and External Devices
14.1 New Items
Added in release 5.1.1
Added support for the following new OPN's: BRD2505A, BRD2713A, BRD4120A, BRD4121A, BRD4402C, BRD4403C.
Added in release 5.1.0
- Added support for the following new drivers: ICM40627- IMU sensor, SHT4X sensor- Humidity and Temperature sensor.
- Added support for the following new OPNs: BRD2709A, BRD2711A, BRD4350A, BRD4351A, BRD4412A, BRD4413A.
14.2 Improvements
Changed in release 5.1.0
None.
14.3 Fixed Issues
Fixed in release 5.1.0
| ID # | Description |
| 1320271 | Microphone: Added EM1 requirement when initializing the microphones to prevent chip from entering Low Energy modes (EM2 through EM4). |
14.4 Known Issues in the Current Release
None.
14.5 Deprecated Items
Deprecated in release 5.1.0
None.
14.6 Removed Items
Removed in release 5.1.0
None.
15 Other Gecko Platform Software Components
15.1 New Items
Added in release 5.1.0
None.
15.2 Improvements
Changed in release 5.1.0
None.
15.3 Fixed Issues
Fixed in release 5.1.0
None.
15.4 Known Issues in the Current Release
| ID # | Description | Workaround |
| An issue is detected when updating the GCC toolchain from version 10.3 to 12.2, which increases the RAM usage by about 400 bytes in some cases when using stdio. | -- |
15.5 Deprecated Items
Deprecated in release 5.1.0
None.
15.6 Removed Items
Removed in release 5.1.0
None.
16 RAIL Library
16.1 New Items
Added in release 5.1.1
- Added RAIL support for the MGM260PD32VNA2, MGM260PD32VNN2, MGM260PD22VNA2, MGM260PB32VNA5, MGM260PB32VNN5, MGM260PB22VNA5, BGM260PB22VNA2 and BGM260PB32VNA2 modules.
Added in release 5.1.0
- Added RAIL_GetRxIncomingPacketRssi to get the RSSI associated with the incoming packet.
- Added support for "RAIL Utility, CS Antenna Offset" component for BLE Channel Sounding feature on EFR32xG24, allowing customer to configure offsets for wired or wireless antenna configurations.
- Added support for TrustZone APIs on EFR32xG23 and EFR32xG28 parts to allow RAIL to access CMU, EMU, GPIO, LDMA, HFXO, PRS and SYSRTC peripherals when running in secure state, even if RAIL library is non-secure.
16.2 Improvements
Changed in release 5.1.3
- Improved automatic LNA bypass on EFR32xG25 by keeping the bypass on after timeout if the power is still above threshold.
Changed in release 5.1.2
- Updated component documentation for "RAIL Utility, External RF Switch Control" and "RAIL Utility, Default Internal RF Path Configuration" to clarify appropriate usage.
- Updated Wi-SUN mode switch channel mask for BZ band in RAILTEST on EFR32xG25.
Changed in release 5.1.1
None.
Changed in release 5.1.0
- To prepare for RAIL 3.0 specifications, RAIL_Status_t is now sl_status_t and RAIL_STATUS_ values are mapped to similar SL_STATUS_ values.
16.3 Fixed Issues
Fixed in release 5.1.3
| ID # | Description |
| 1447400 | Fixed an issue in RAIL_GetRxPacketDetails() where the duration of the packet would be incorrect when packet size is larger than 534 bytes on EFR32xG25. |
| 1450403 | Fixed an issue on EFR32xG23, EFR32xG25, EFR32xG26 and EFR32xG28 where radio was blocked in RAIL_RF_STATE_RX_ACTIVE. |
| 1455258 | Fixed a BLE scan response timing issue that could affect BLE-related applications on 20dBm EFR32xG21 devices interacting with non Silabs devices. |
| 1479421 | Updated the quality of the Fast Channel Switching Configuration component to Production. |
Fixed in release 5.1.2
| ID # | Description |
| 1389592 | Fixed an issue in "RAIL Utility, Coexistence" component where enabling Grant, Priority, and Request signals would cause a hard fault in Matter + BLE multiprotocol application. |
| 1412900 | Fixed an issue in the "RAIL Utility, CS Antenna Offset" component where array lengths of wired and wireless antenna offset values were fixed to a default size regardless of the antenna count of a selected board. |
| 1426191 | Fixed an issue in dynamic multiprotocol applications where a radio does not enter into EM2 sleep mode when no active tasks are being performed. |
Fixed in release 5.1.1
| ID # | Description |
| 1172597 | Fixed an issue with RAIL_RX_CHANNEL_HOPPING_MODE_MANUAL where RAIL_EVENT_RX_CHANNEL_HOPPING_COMPLETE wouldn't be signaled. Added new RAIL_TriggerRxChannelHop() API for manually triggering an RX channel hop. Noted that RAIL_RX_CHANNEL_HOPPING_OPTION_STOP was only intended for testing purposes and is not supported on EFR32xG21. |
| 1349369 | Fixed an issue where power restrictions were incorrectly applied through channel configs on platforms that support RAIL_SUPPORTS_DBM_POWERSETTING_MAPPING_TABLE. |
| 1380153 | Fixed an issue where calling RAIL_Idle() could prevent any future reception on EFR32xG25 for OFDM-FSK concurrent PHYs. |
| 1389189 | Fixed a false channel busy issue when automatic LNA bypass is enabled on EFR32xG25. |
Fixed in release 5.1.0
| ID # | Description |
| 1120643 | Fixed an issue where the phy was not re-configured correctly when using RAIL_ConfigSyncWords API with certain custom modem configurations. |
| 1273595 | Renamed RAIL_ZWAVE_REGION_US_LR_END_DEVICE to RAIL_ZWAVE_REGION_US_LR3, RAIL_ZWAVE_REGION_EU_LR_END_DEVICE to RAIL_ZWAVE_REGION_EU_LR3, RAIL_ZWAVE_REGIONID_US_LR_END_DEVICE to RAIL_ZWAVE_REGIONID_US_LR3, and RAIL_ZWAVE_REGIONID_EU_LR_END_DEVICE to RAIL_ZWAVE_REGIONID_EU_LR3 to better reflect Z-Wave spec naming conventions. |
| 1290731 | Fixed a multiprotocol issue where RAIL_BLE_SetNextTxRepeat() or RAIL_SetNextTxRepeat() information mistakenly survived across RAIL_Idle() to the surprise of a subsequent non-repeated transmit. |
| 1300509 | Fixed an issue with IEEE 802.15.4 High Data Rate (HDR) packets such that PTI now properly indicates they have a 2-byte 802.15.4 PHY header on EFR32xG26. |
| 1306804 | Fixed an issue where glitches could occur when using RAIL_RxDataSource_t values other than RX_PACKET_DATA on EFR32xG23 and newer chips. |
| 1309139 | Fixed an issue on EFR32xG22 and later where RAIL_StopTx() being called before the transmit has started could cause the radio to return to receive with the radio partially misconfigured for transmit. |
| 1309208 | Fixed a minor issue on EFR32xG21 where the TX-to-RX turnaround timing could be a bit longer than specified. |
| 1321076 | Fixed an issue with setDebugSignal railtest command that broke DOUT and DCLK signals. |
| 1352393 | Fixed an issue on ZGM230S modules where PHY signatures were computed incorrectly, and the device would assert on startup. |
| 1357948 | Fixed a DMP issue where the device would incorrectly switch to a background receive task with insufficient time to switch back to an upcoming high priority scheduled task. |
| 1369901 | Fixed an issue where the device would become stuck when running image rejection calibration on an OFDM PHY from the event callback on EFR32xG25. |
16.4 Known Issues in the Current Release
| ID # | Description | Workaround |
| Using direct mode (or IQ) functionality on EFR32xG23 requires a specifically set radio configuration not yet supported by the radio configurator. | Reach out to technical support for configuration. | |
| 641705 | Infinite receive operations where the frame's fixed length is set to 0 are not working correctly on EFR32xG23 series chips. | |
| 732659 | On EFR32xG23: Wi-SUN FSK mode 1a exhibits a PER floor with frequency offsets around ±8 to 10 KHz. Wi-SUN FSK mode 1b exhibits a PER floor with frequency offsets around ±18 to 20 KHz. |
16.5 Deprecated Items
Deprecated in release 5.1.0
- The RAIL 2.x API is planned for deprecation in the 2025.6.0 release (December 2025). The new RAIL 3.0 API will be released with a compatibility layer and migration guide.
- RAIL 3.0 API is in evaluation in sl_rail_*.h files, subject to change. The RAIL library has RAIL 3.0 symbols alongside RAIL 2.x.
16.6 Removed Items
Removed in release 5.1.0
None.
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Disclaimer
Silicon Labs provides the latest, accurate, and in-depth documentation for its products. Characterization data, modules, peripherals, memory sizes, and addresses refer to specific devices, and typical parameters can vary. Application examples are for illustrative purposes only. Silicon Labs reserves the right to make changes without further notice to product information, specifications, and descriptions, and does not warrant accuracy or completeness. Silicon Labs may update product firmware without prior notification for security or reliability reasons; such changes will not alter specifications or performance. Silicon Labs shall have no liability for the consequences of using the information supplied. This document does not grant any license to design or fabricate integrated circuits. Products are not designed or authorized for use in FDA Class III devices, applications requiring FDA premarket approval, or Life Support Systems without written consent. Silicon Labs products are not designed or authorized for military applications or for use in weapons of mass destruction. Silicon Labs disclaims all warranties and shall not be responsible for any injuries or damages related to unauthorized applications.
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