Define an explicit allowlist of externally bindable symbols, build the library with that policy, and compare the resulting dynamic definitions against the list. A public header alone does not prevent unrelated global functions from becoming part of an ELF shared library’s exported surface. Once consumers bind to an accidental export, removing it can become a…
A fixture change does not automatically invalidate every earlier pass, but neither does a new successful station check validate all old results. Select earlier unit results by the measurement path, fixture/calibration revision and exposure interval that the change could affect. Hold records with insufficient scope evidence instead of treating missing metadata as proof that they…
Do not enable CAN FD frames on an existing segment until every connected node is qualified for the frames it will encounter, or isolated by a verified architecture. Upgrading one controller and setting a faster data bitrate does not establish network compatibility. The inventory must include normal firmware, bootloaders, service adapters, sleeping nodes, and replacement…
Build one software transaction around the chip-select interval required by the peripheral. A command transfer followed by a data transfer can be correct when both belong to one SPI message, yet fail when issued as two independent operations that release chip select between them. Prove the intended grouping with a waveform capture, not just a…
Measure SDA and SCL before choosing recovery. A target holding SDA low may respond to a bounded bus-clear sequence; a line physically clamped low will not. If SCL cannot rise, generating more software clock requests is not a remedy. Resetting the controller, resetting a peripheral, and cycling a power domain affect different state and must…
Enabling CONFIG_NVS_DATA_CRC changes how Zephyr NVS interprets stored elements. Export and validate existing settings while a compatible reader can still read them, then import them into a deliberately prepared CRC-enabled store. Simply changing the build option does not append checksums to records already in flash. Applicability: this article checks Zephyr v4.2.0 documentation, Kconfig, API declarations,…
littlefs can keep filesystem operations consistent across power loss without making two application files one transaction. If a product needs both files to describe the same configuration, publish them through one durable selection point. Test recovery at that point and between every preparation step, rather than accepting a successful mount as proof of valid application…
RAUC HTTP streaming requires a compatible bundle, the necessary target kernel support, and working byte-range access through the complete network path. Prove those prerequisites before comparing installation time or removing local staging capacity. A browser downloading the whole bundle successfully does not exercise the access pattern that streaming installation needs. This guide is pinned to…
When only one MCU has advanced, the product must enter a deliberately supported intermediate state or a defined restricted state. Do not let “both images downloaded” stand in for a coordinated update. Specify which version pairs can communicate, which functions remain available, and how the next transition proceeds after either processor resets. This article proposes…
Choose an MCUboot swap mode from flash geometry, usable image capacity, per-region erase cost, and interrupted-update recovery. A small scratch partition can save address space while concentrating erase cycles. Removing scratch does not remove flash wear; offset and move modes distribute work differently and impose their own layout requirements. This comparison is pinned to the…