The Memfault module provides an integration of Memfault SDK into nRF Connect SDK and expands the functionality of the SDK with some options that are specific to nRF Connect SDK.
The SDK provides a functionality to collect debug information from devices in the form of coredumps, error traces, metrics, logs and more. Information that is collected from the device can be sent to Memfault’s cloud solution for further analysis. Communication with the Memfault Cloud is handled by APIs available in Memfault SDK, while the integration code of the SDK in nRF Connect SDK provides some additional functionality.
For official documentation for Memfault SDK and the Memfault platform in general, see Memfault Docs.
See the nRF9160: Memfault sample for an example of Memfault implementation in nRF Connect SDK.
Memfault in nRF Connect SDK currently supports the nRF9160-based build targets.
The SDK is part of the West manifest in nRF Connect SDK and is automatically downloaded when running
By default, it is downloaded to
<nRF Connect SDK path>/modules/lib/memfault-firmware-sdk/.
To include Memfault in your build, enable the Kconfig option
The APIs in Memfault SDK can then be linked into your application.
In addition, you must configure a Memfault project key using
CONFIG_MEMFAULT_NCS_PROJECT_KEY is located in
To get access to all the benefits, like up to 100 free devices connected, register at the Memfault registration page.
In general, configuration of Memfault SDK in nRF Connect SDK is done using Kconfig options.
Kconfig options are defined both in Memfault SDK and in the integration layer, which integrates the SDK into nRF Connect SDK.
Kconfig options of the integration layer are located in
These Kconfig options are differentiated by two distinct prefixes:
CONFIG_MEMFAULT_- Prefix for options defined in Memfault SDK
CONFIG_MEMFAULT_NCS_- Prefix for options defined in nRF Connect SDK
If you just want to do a quick test with a sample, disable the
CONFIG_MEMFAULT_USER_CONFIG_ENABLE option in the
prj.conf to avoid adding the user configuration files.
Otherwise, follow the instructions below.
Memfault SDK requires three files in the include path during the build process.
Add a new folder into your project called
config and add the following three files:
memfault_platform_config.h- Sets Memfault SDK configurations that are not covered by Kconfig options
memfault_metrics_heartbeat_config.def- Defines application-specific metrics
memfault_trace_reason_user_config.def- Defines application-specific trace reasons
For more information, you can see Memfault nRF Connect SDK integration guide.
You can use the files in the nRF9160: Memfault sample as a reference.
To have these configuration files in the include path, add the following in the
Following are some of the configuration options that Memfault SDK define:
You can find more details on each option using
guiconfig, and in the Kconfig sources in
The Memfault shell is enabled by default, using the UART interface.
If AT Host library and the memfault module are enabled simultaneously, both will not behave as expected, as they both require the UART same interface.
Therefore, it is recommended to only enable one of these at the same time.
To disable the Memfault shell, you need to disable the two configurations,
The Kconfig options for Memfault that are defined in nRF Connect SDK provide some additional features compared to the options that are already implemented in Memfault SDK:
The nRF Connect SDK integration of Memfault SDK provides default values for some metadata that are required to identify the firmware when it is sent to Memfault cloud. These defaults can be controlled by using the configuration options below:
- group memfault_ncs
Convenience functions for using Memfault firmware SDK with nRF Connect SDK.
int memfault_ncs_device_id_set(const char *device_id, size_t len)
Set the Memfault device ID.
In order to use this API successfully, CONFIG_MEMFAULT_NCS_DEVICE_ID_RUNTIME must be enabled.
device_id – Pointer to device ID buffer
len – Length of device ID. Can not exceed CONFIG_MEMFAULT_NCS_DEVICE_ID_MAX_LEN.
0 on success, otherwise a negative error code
- int memfault_ncs_device_id_set(const char *device_id, size_t len)