External Watchdog Timing Sync Across Bootloader and Application

The patent introduces a shared memory area as an intermediary between the bootloader/application and the external watchdog module. This shared memory stores the last watchdog refresh timing information, allowing the software components to accurately determine window open time without directly accessing the watchdog module's internal timing mechanisms. The intermediary resolves the contradiction by enabling precise timing measurement while maintaining the safety benefits of external watchdog monitoring.

The patent implements dynamic timing adaptation by having the bootloader or application check the stored last watchdog refresh timing against the current time to determine if the current moment falls within the window open time. This dynamic approach allows the system to adapt to different operational phases (bootloader vs. application execution) while ensuring watchdog refreshes only occur during valid window open periods, preventing false failure recognition during window close time.

The patent segments the memory structure into a dedicated shared memory area that is separate from the main software execution areas. This shared memory specifically stores the last watchdog refresh timing, creating a specialized data storage segment that enables accurate timing synchronization. The segmentation approach maintains relatively simple device complexity by using a focused, purpose-built memory segment rather than a complex distributed timing system.