The Watchdog reference article from the English Wikipedia on 24-Jul-2004 (provided by Fixed Reference: snapshots of Wikipedia from wikipedia.org)

Watchdog

A watchdog is a dog that is intended to watch, to warn of approach of strangers or animals.

Computing

In computing or embedded systems, a watchdog is a hardware timing device that triggers a system reset if the main program neglects to regularly service the watchdog. The intention is to bring the system back into normal operation. It is effectively a missing pulse detector.

Watchdog timers may be more complex, attempting to save information useful for debugging what caused the fault onto a persistent medium when a fault is detected. In this case, a second watchdog timer ensures that if the first watchdog timer does not complete its task of saving debugging information in a certain amount of time, the system will reset with or without the information saved.

Watchdog timers may also trigger control systems to move into a safety state, such as turning off motors, or disabling other potentially dangerous subsystems until the fault is cleared.

Consumer protection

A watchdog is also an informal name given to consumer protection organisations or campaigners. Their aim is to highlight criminality and poor service provided by companies and public bodies. In the UK, there is a long-running BBC programme called Watchdog that fills such a role.

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