memfault

Overview

This example demonstrates how to use Memfault SDK to collect fault data. The dumped data is saved to flash, and can be sent to Memfault cloud for analysis. For more dtails, please refer to: https://memfault.com/

NOTE Only flash targets are supported!

This project only dumps some necessary memory regions, if you want to dump more, please refer to the memfault document: https://docs.memfault.com/docs/mcu/coredumps#choosing-what-to-store-in-a-coredump, and create your own function memfault_platform_coredump_get_regions to override the default one which is a weak function in file memfault_platform_port.c.

Configuration

A flash region is reserved for memfault dumped data, this flash region position and size can be configured.

When use Kconfig, go to the “Component Configuration -> Debug -> MemFault SDK”, configure the “Backend flash offset” and “Backend flash size”. When use the package without Kconfig, modify the macros CONFIG_MEMFAULT_FLASH_BASE_OFFSET and CONFIG_MEMFAULT_FLASH_SIZE in file “mcux_config.h”.

NOTE When the flash region is reconfigured, the linker script should be updated too, to make sure the flash region match.

Running the project

Follow the instructions in the terminal, press ‘A’ to trigger a fault. When the fault occurs, MCU will dump the data to flash reset. After reset, press ‘B’ to show the dumped data and send the data to Memfault cloud to check.

After ‘B’ is pressed, the dumped data is cleared from flash, so if ‘B’ is pressed again, no data will be shown.

Option ‘C’ is self test, if run pass, Test successed will be printed. Note If run ‘A’ then ‘C’, the test will fail, because there is valid dump data in flash, selftest can’t erase the dump data.

Analyze the dumped result

There are two methods to analyze the dumped result: Upload dumped data chunk to Memfault server, or debug use GDB.

Upload data chunk to Memfault server

When ‘B’ is pressed, the data chunks are shown in the terminal, post the data following such guide: https://docs.memfault.com/docs/mcu/export-chunks-over-console

Debug with GDB

  1. Install the python tool using command pip install memfault-core-convert. Details of this tool is: https://pypi.org/project/memfault-core-convert/

  2. Export the dumped data in flash, for example, using gdb command like, dump binary memory memfault-core.bin 0x00010000 0x00018000, fill the right flash address according to your settings.

  3. Generate the core elf file use memfault-core-convert --file memfault-core.bin --out_elf core.elf

  4. Run GDB to debug: arm-none-eabi-gdb -se memfault.elf --core core.elf, here memfault.elf is current project image.

Detailed steps can be found here: https://docs.memfault.com/docs/mcu/coredump-elf-with-gdb.

Supported Boards