In the Memfault UI:
- Click Devices in the left toolbar to see devices that have reported in.
- Select a device to inspect its coredumps, metrics, and event history.
Coredumps are captured automatically on crashes (RAM-backed, 3 KB) and are truncated if a crash needs more space than that. Without an uploaded symbol file, traces appear with a Symbols Missing label and cannot be decoded. Memfault matches a coredump to its symbol file by the GNU build ID that the application logs at boot (<inf> mflt: GNU Build ID: ...), so the symbol file has to come from the exact build running on the device; rebuilding the same version produces a different build ID.
Because TF-M owns the fault handlers for HardFaults, only BusFaults and SecureFaults originating in non-secure code reach Memfault's handler (CONFIG_TFM_ALLOW_NON_SECURE_FAULT_HANDLING=y). A mflt test hardfault is trapped by TF-M, which halts the core without collecting a coredump; use mflt test busfault instead.