- External antenna performance setting
The preprogrammed Asset Tracker does not come with the best external antenna performance.
Workaround: If you are using nRF9160 DK v0.15.0 or higher and Thingy:91 v1.4.0 or higher, set
y. Alternatively, for nRF9160 DK v0.15.0, you can set the
AT%XCOEX0when building the preprogrammed Asset Tracker to achieve the best external antenna performance.
- NCSDK-5574: Warnings during FOTA
The nRF9160: Asset Tracker application prints warnings and error messages during successful FOTA.
- NCSDK-6689: High current consumption in Asset Tracker
The nRF9160: Asset Tracker sample might show up to 2.5 mA current consumption in idle mode with
- Sending data before connecting to nRF Cloud
The nRF9160: Asset Tracker sample does not wait for connection to nRF Cloud before trying to send data. This causes the sample to crash if the user toggles one of the switches before the board is connected to the cloud.
- NCSDK-5666: LTE Sensor Gateway
The nRF9160: LTE Sensor Gateway sample crashes when Thingy:52 is flipped.
nrf_send()function in the BSD library might be blocking for several minutes, even if the socket is configured for non-blocking operation. The behavior depends on the cellular network connection.
Workaround: For nRF Connect SDK v1.4.0, set the non-blocking mode for a partial workaround for non-blocking operation.
- GPS sockets and SUPL client library stops working
Workaround: Insert a delay (
k_sleep()) of a few seconds after the
printfon line 294 in
- Calling nrf_connect immediately causes fail
nrf_connect fails if called immediately after initialization of the device. A delay of 1000 ms is required for this to work as intended.
- Problems with RTT Viewer/Logger
The SEGGER Control Block cannot be found by automatic search by the RTT Viewer/Logger.
Workaround: Set the RTT Control Block address to 0 and it will try to search from address 0 and upwards. If this does not work, look in the
builddir/zephyr/zephyr.mapfile to find the address of the
_SEGGER_RTTsymbol in the map file and use that as input to the viewer/logger.
- Receive error with large packets
nRF91 fails to receive large packets (over 4000 bytes).
- Modem FW reset on debugger connection through SWD
If a debugger (for example, J-Link) is connected via SWD to the nRF9160, the modem firmware will reset. Therefore, the LTE modem cannot be operational during debug sessions.
CMakeLists.txtfile for developing applications that emulate nRF52820 on the nRF52833 DK is missing.
Workaround: Create a
CMakeLists.txtfile in the
ncs/zephyr/boards/arm/nrf52833dk_nrf52820folder with the following content:
You can download this file from the upstream Zephyr repository. After you add it, the file is automatically included by the build system.
- KRKNWK-7803: Automatically generated libraries are missing otPlatLog for NCP
When building OpenThread libraries using a different sample than the Thread NCP sample, the
ncp_base.cppis not compiled with the
otPlatLog()function. This results in a linking failure when building the NCP with these libraries.
Workaround: Use the Thread NCP sample to create OpenThread libraries.
- NCSDK-5014: Building with SES not possible
It is not possible to build Thread samples using SEGGER Embedded Studio (SES). SES does not support
.cppfiles in nRF Connect SDK projects.
- KRKNWK-6358: CoAP client sample provisioning issues
It is not possible to provision the Thread: CoAP Client sample to servers that it cannot directly communicate with. This is because Link Local Address is used for communication.
diagcommand not supported
diagcommand is not yet supported by Thread in the nRF Connect SDK.
- KRKNWK-6073: Potential delay during FOTA
There might be a noticeable delay (~220 ms) between calling the ZBOSS API and on-the-air activity.
- KRKNWK-6071: ZBOSS alarms inaccurate
On average, ZBOSS alarms last longer by 6.4 percent than Zephyr alarms.
Workaround: Use Zephyr alarms.
- DESK-978: Directed advertising issues with SoftDevice Link Layer
Directed advertising (
CONFIG_DESKTOP_BLE_DIRECT_ADV) should not be used by the nRF Desktop application when the SoftDevice Controller is in use, because that leads to reconnection problems. For more detailed information, see the
Known issues and limitationssection of the SoftDevice Controller’s Changelog.
Workaround: Directed advertising is disabled by default for nRF Desktop.
- NCSDK-5711: High-throughput transmission can deadlock the receive thread
High-throughput transmission can deadlock the receive thread if the connection is suddenly disconnected.
- Only secure applications can use Bluetooth LE
Bluetooth LE cannot be used in a non-secure application, for example, an application built for the
Workaround: Use the
- Peripheral HIDS keyboard sample cannot be used with nRF Bluetooth LE Controller
The Bluetooth: Peripheral HIDS keyboard sample cannot be used with the SoftDevice Controller because the NFC subsystem does not work with the controller library. The library uses the MPSL Clock driver, which does not provide an API for asynchronous clock operation. NFC requires this API to work correctly.
- Peripheral HIDS mouse sample advertising issues
When the Bluetooth: Peripheral HIDS mouse sample is used with the Zephyr Bluetooth LE Controller, directed advertising does not time out and the regular advertising cannot be started.
- Central HIDS sample issues with directed advertising
The Bluetooth: Central HIDS sample cannot connect to a peripheral that uses directed advertising.
- Unstable samples
Bluetooth Low Energy peripheral samples are unstable in some conditions (when pairing and bonding are performed and then disconnections/re-connections happen).
When running the Bluetooth: Central DFU SMP sample, the
CONFIG_BT_SMPconfiguration must be aligned between this sample and the Zephyr counterpart (SMP Server Sample). However, security is not enabled by default in the Zephyr sample.
- Reconnection issues on some operating systems
On some operating systems, the nRF Desktop application is unable to reconnect to a host.
- Bluetooth: Central UART cannot handle long strings
A too long 212-byte string cannot be handled when entered to the console to send to Bluetooth: Peripheral UART.
- Bluetooth: Central HIDS loses UART connectivity
After programming a HEX file to the nrf52_pca10040 board, UART connectivity is lost when using the BLE Controller. The board must be reset to get UART output.
- Samples crashing on nRF51 when using GPIO
On nRF51 devices, Bluetooth LE samples that use GPIO might crash when buttons are pressed frequently. In such case, the GPIO ISR introduces latency that violates real-time requirements of the Radio ISR. nRF51 is more sensitive to this issue than nRF52 (faster core).
- GATT Discovery Manager missing support
The GATT Discovery Manager is not supported on nRF51 devices.
- Samples do not work with SD Controller v0.1.0
Bluetooth LE samples cannot be built with the SoftDevice Controller v0.1.0.
- LED Button Service reporting issue
Bluetooth: Peripheral LBS does not report the Button 1 state correctly.
- MITM protection missing for central samples
- Peripheral UART string size issue
Bluetooth: Peripheral UART cannot handle the corner case that a user attempts to send a string of more than 211 bytes.
- Reconnection issues after bonding
The peripheral samples (Bluetooth: Peripheral UART, Bluetooth: Peripheral LBS, Bluetooth: Peripheral HIDS mouse) have reconnection issues after performing bonding (LE Secure Connection pairing enable) with nRF Connect for Desktop. These issues result in disconnection.
- NCSDK-5580: nRF5340 only supports SoftDevice Controller
On nRF5340, only the SoftDevice Controller is supported for Bluetooth Mesh.
- Public keys revocation
Public keys are not revoked when subsequent keys are used.
- Incompatibility with nRF51
The bootloader does not work properly on nRF51.
- Immutable bootloader not supported in SES
Building and programming the immutable bootloader (see Secure bootloader chain) is not supported in SEGGER Embedded Studio.
- Immutable bootloader board restrictions
The immutable bootloader can only be used with the following boards:
- KRKNWK-7827: Application build system is not aware of the settings partition
The application build system is not aware of partitions, including the settings partition, which can result in application code overlapping with other partitions. As a consequence, writing to overlapping partitions might remove or damage parts of the firmware, which can lead to errors that are difficult to debug.
Workaround: Define and use a code partition to shrink the effective flash memory available for the application. You can use one of the following solutions:
Partition Manager from nRF Connect SDK - see the page for all configuration options. For example, for single image (without bootloader and with the settings partition used), set the
CONFIG_PM_SINGLE_IMAGEKconfig option to
yand define the value for
CONFIG_PM_PARTITION_SIZE_SETTINGS_STORAGEto the required settings storage size.
- Build configuration issues
Workaround: Either include MCUboot in the build or use MCUboot instead of the immutable bootloader.
- Flash commands only program one core
ninja flashonly program one core, even if multiple cores are included in the build.
Workaround: Execute the flash command from inside the build directory of the child image that is placed on the other core (for example,
- Secure Partition Manager and application building together
It is not possible to build and program Secure Partition Manager and the application individually.
- NCSDK-6238: Socket API calls may hang when using Download client
When using the Download client library with HTTP (without TLS), the application might not process incoming fragments fast enough, which can starve the BSD library buffers and make calls to BSD library hang. Samples and applications that are affected include those that use Download client to download files through HTTP, or those that use FOTA download with modem updates enabled.
- Jobs not received after reset
When using AWS FOTA, no new jobs are received on the device if the device is reset during a firmware upgrade or loses the MQTT connection.
Workaround: Delete the stalled in progress job from AWS IoT.
- Stalled download
FOTA download does not resume a download if the device loses the connection.
fota_download_start()again with the same arguments when the connection is re-established to resume the download.
- Offset not retained with an MCUboot target
When using the MCUboot target in DFU target, the write/downloaded offset is not retained when the device is reset.
- Download stopped on socket connection time-out
In the nRF9160: AWS FOTA and nRF9160: HTTP application update samples, the download is stopped if the socket connection times out before the modem can delete the modem firmware. A fix for this issue is available in commit 38625ba7.
fota_download_start()again with the same arguments.
- Update event triggered by an error event
If the last fragment of a FOTA download is received but is corrupted, or if the last write is unsuccessful, the library emits an error event as expected. However, it also emits an apply/request update event, even though the downloaded data is invalid.
- FW upgrade is broken for multi-image builds
Firmware upgrade using mcumgr or USB DFU is broken for multi-image builds, because the devicetree configuration is not used. Therefore, it is not possible to upload the image.
Workaround: Build MCUboot and the application separately.
- Sample incompatibility with the nRF5340 PDK
The NFC: TNEP poller and NFC: Tag reader samples cannot be run on the nRF5340 PDK. There is an incorrect number of pins defined in the MDK files, and the pins required for NFC Reader ST25R3911B cannot be configured properly.
- Unstable NFC tag samples
NFC tag samples are unstable when exhaustively tested (performing many repeated read and/or write operations). NFC tag data might be corrupted.
- NCSIDB-114: Default logging causes crash
Enabling default logging in the Secure Partition Manager sample makes it crash if the sample logs any data after the application has booted (for example, during a SecureFault, or in a secure service). At that point, RTC1 and UARTE0 are non-secure.
Workaround: Do not enable logging and add a breakpoint in the fault handling, or try a different logging backend.
- Recovery with the USB does not work
The MCUboot recovery feature using the USB interface does not work.
- NCSDK-5883: CMAC behavior issues
CMAC glued with multiple backends may behave incorrectly due to memory allocation issues.
Workaround: Disable glued CMAC and use only one of the enabled backends.
- NCSDK-5546: Oberon missing symbols for HKDF
nRF Oberon v3.0.5 is missing symbols for HKDF using SHA1, which will be fixed in an upcoming version of the library.
Workaround: Use a different backend (for example, vanilla mbed TLS) for HKDF/HMAC using SHA1.
- Limited support for Nordic Security Module
The Nordic Security Module is currently only fully supported on nRF52840 and nRF9160 devices. It gives compile errors on nRF52832, nRF52833, nRF52820, nRF52811, and nRF52810.
Workaround: To fix the errors, cherry-pick commits in nrfxlib PR #205.
- Glue layer symbol renaming issue
The Nordic Security Module glue layer is broken because symbol renaming is not handled correctly. Therefore, the behavior is undefined when selecting multiple back-ends for the same algorithm (for example, AES).
- Cold start and A-GPS data not supported
Forcing a cold start and writing A-GPS data is not yet supported.
- Hard-fault with GPS in running mode
Implementation might hard-fault when GPS is in running mode and messages are not read fast enough.
- NMEA strings might return wrong length
NMEA strings are valid c-strings (0-terminated), but the read function might return wrong length.
- Closing sockets
Sockets can only be closed when GPS is in stopped mode. Moreover, closing a socket does not properly clean up all memory resources. If a socket is opened and closed multiple times, this might starve the system.
The following known issues and limitations have been moved from MPSL’s changelog for the nRF Connect SDK v1.4.0 release.
- DRGN-6362: Do not use the synthesized low frequency clock source
The synthesized low frequency clock source is neither tested nor intended for usage with MPSL.
- DRGN-14153: Radio Notification power performance penalty
The Radio Notification feature has a power performance penalty proportional to the notification distance. This means an additional average current consumption of about 600 µA for the duration of the radio notification.
- Front-End Modules API implementation missing
Front-End Modules API is currently not implemented by any protocol.
The following known issues and limitations have been moved from SD Controller’s changelog for the nRF Connect SDK v1.4.0 release.
- DRGN-8476: Long packets not supported in connections on Coded PHY
In connections, the Link Layer payload size is limited to 27 bytes on LE Coded PHY.
- DRGN-9083: AAR populated with zero IRK
If the application has set an all zeroes IRK for a device in the resolving list, then a resolvable address that can be resolved with the all zeroes IRK will be reported to the application as that device in the advertisement report or the connected event.
- DRGN-10659: Directed advertising issues using RPA in TargetA
The SoftDevice Controller will generate a resolvable address for the TargetA field in directed advertisements if the target device address is in the resolving list with a non-zero IRK, even if privacy is not enabled and the local device address is set to a public address.
Workaround: Remove the device address from the resolving list.
- DRGN-11297: Maximum CI before entering LLPM-mode
The maximum connection interval that can be active when switching to a connection interval of 1 ms is 10 ms.
Workaround: An application that needs to use a higher interval than 10 ms needs to perform two connection updates to use 1 ms connection interval:
A first update to 10 ms connection interval.
A second update to 1 ms connection interval.
- DRGN-10305: Scanner can’t have more than 16 seconds scan window
If the scanner is configured with a scan window larger than 16 seconds, the scanner will truncate the scan window to 16 seconds.
- DRGN-8569: SEVONPEND flag must not be modified
Applications must not modify the SEVONPEND flag in the SCR register when running in priority levels higher than 6 (priority level numerical values lower than 6) as this can lead to undefined behavior.
- DRGN-6362: Synthesized low frequency clock source not tested
Synthesized low frequency clock source is not tested or intended for use with the Bluetooth LE stack.
- DRGN-10367: Advertiser times out earlier than expected
If an extended advertiser is configured with limited duration, it will time out after the first primary channel packet in the last advertising event.
- DRGN-12259: HCI Receiver and Transmitter Test commands not available
The HCI Receiver and Transmitter Test commands are not available.
Workaround: To perform a radio test, use a DTM application:
For nRF52, use the DTM application in the nRF5 SDK.
For nRF53, use Bluetooth: Direct Test Mode.
CONFIG_BT_HCI_TX_STACK_SIZErequires specific value
CONFIG_SYSTEM_WORKQUEUE_STACK_SIZErequires specific value
CONFIG_NFCT_IRQ_PRIORITYrequires specific value
- Several issues for nRF5340
The following issues can occur when using SoftDevice Controller with nRF5340:
Poor performance when performing active scanning.
The controller could assert when receiving extended advertising packets.
T_IFScould in certain conditions be off by 5 us.
The radio could stay in the TX state longer than expected. This issue can only occur when sending a packet on either LE 1M or LE 2M PHY after receiving or transmitting a packet on LE Coded PHY. If this occurs while performing a Link Layer Control Procedure, the controller could end up retransmitting an acknowledged packet, resulting in a disconnect.
- Sending control packet twice
A control packet could be sent twice even after the packet was acknowledged. This would only occur if the radio was forced off due to an unforeseen condition.
- Wait time required after a directed high duty cycle advertiser times out
The application is unable to restart a connectable advertiser right after a high-duty-cycle advertiser times out.
Workaround: Wait 500 ms before restarting a connectable advertiser
- Assert risk after performing a DLE procedure
The controller could assert when receiving a packet with a CRC error on LE Coded PHY after performing a DLE procedure where RX Octets is changed to a value above 140.
- Assert when using HCI LE Set Extended Advertising Parameters
The controller will assert when setting secondary PHY to 0 when using HCI LE Set Extended Advertising Parameters and the advertising type is set to legacy advertising.
- HCI issues with duplicate filtering
HCI LE Set Extended Scan Enable returns UNSUPPORTED_FEATURE when duplicate filtering is enabled.
- HCI issues with secondary_max_skip
HCI LE Set Advertising Parameters returns UNSUPPORTED_FEATURE when secondary_max_skip is set to a non-zero value.
- No data issue when connected to multiple devices
hci_data_get()may return “No data available” when there is data available. This issue will only occur when connected to multiple devices at the same time.
- Assert on LE Write Suggested Default Data Length
The controller will assert if the host issues LE Write Suggested Default Data Length.
- HCI LE Set Privacy Mode appears as not supported
The controller does not indicate support for HCI LE Set Privacy Mode although it is supported.
- Assert if advertising data is set after HCI Reset
The controller will assert if advertising data is set after HCI Reset without first setting advertising parameters.
- Assert on writing to flash
The controller may assert when writing to flash.
- Time-out without sending packet
A directed advertiser may time out without sending a packet on air.
- Incorrect pin definition for nRF5340
For nRF5340, the pins P1.12 to P1.15 are unavailable due to an incorrect pin number definition in the MDK.
- Samples might be swapped
Samples might be swapped when buffer is set after starting the sample process, when more than one channel is sampled. This can happen when the sample task is connected using PPI and setting buffers and sampling are not synchronized.
- RX and TX not disabled in uninit
The driver does not disable RX and TX in uninit, which can cause higher power consumption.
- NCSDK-6330: USB Mass Storage Sample Application fails MSC Tests from USB3CV test tool
USB Mass Storage Sample Application fails the USB3CV compliance Command Set Test from the MSC Tests suite.
- NCSDK-6328: USB CDC ACM Composite Sample Application fails Chapter 9 Tests from USB3CV test tool
USB CDC ACM Sample Composite Application fails the USB3CV compliance TD 9.1: Device Descriptor Test from the Chapter 9 Test suite.
- NCSDK-6331: WebUSB sample application fails Chapter 9 Tests from USB3CV test tool
WebUSB sample application fails the USB3CV compliance TD 9.21: LPM L1 Suspend Resume Test from the Chapter 9 Test suite.
- NCSIDB-108: Thread context switch might lead to a kernel fault
If the Zephyr kernel preempts the current thread and performs a context switch to a new thread while the current thread is executing a secure service, the behavior is undefined and might lead to a kernel fault. To prevent this situation, a thread that aims to call a secure service must temporarily lock the kernel scheduler (
k_sched_lock()) and unlock the scheduler (
k_sched_unlock()) after returning from the secure call.
- Counter Alarm sample does not work
- USB Mass Storage Sample Application compilation issues
USB Mass Storage Sample Application does not compile.
- NCSDK-6832: SMP Server sample fails upon initialization
The SMP Server Sample will fail upon initialization when using the
bt-overlay.confKconfig overlay file. This happens because of a stack overflow.
In addition to these known issues, check the current issues in the official Zephyr repository, since these might apply to the nRF Connect SDK fork of the Zephyr repository as well. To get help and report issues that are not related to Zephyr but to the nRF Connect SDK, go to Nordic’s DevZone.