Watchdog Timer
A hardware or software timer that triggers recovery when software fails to refresh it within an expected execution interval.
Embedded-System Context
A watchdog timer triggers recovery when software fails to refresh it within an expected interval. Embedded and safety-oriented systems use it to recover from hangs, deadlocks, or stalled control loops, but the refresh point must represent genuine system health.
Failure-Detection Boundary
Feeding a watchdog unconditionally from any active loop defeats the mechanism. If the refresh operation can succeed while critical work is already broken, the watchdog no longer provides a meaningful health signal.
Related Embedded-System Concepts
- RTOS
- Deadlock
- Worst-Case Execution Time
- Fault Recovery