US Patent 7966527 Watchdog mechanism with fault recovery

A method for handling watchdog events of an electronic device includes detecting a watchdog fault in a normal mode, which is a watchdog event in which a watchdog trigger is not correctly serviced; entering from the normal mode into a first escalation level of nx escalation levels upon detection of the watchdog fault, wherein nx is an integer equal to or greater than 1; detecting correct watchdog events, which are watchdog events in which a watchdog trigger is correctly serviced; and concurrently detecting watchdog faults, leaving the first escalation level if a first escalation condition is met, and recovering in a recovering step back from any of the nx escalation levels to a previous level or mode, if a de-escalation condition is met. An electronic device embodiment includes a CPU and program instructions for carrying out the method.