What is the main function of a watchdog timer?

The primary function of a watchdog timer is to monitor the operation of a system and perform a reset if the system becomes unresponsive or fails to execute a specific task within a predetermined time frame. This is critical in embedded systems and other applications where reliability is essential, as it ensures that if the software or firmware hangs or enters an infinite loop, the watchdog timer can detect this and force a system reset, thereby restoring functionality.

By implementing a watchdog timer, the system can recover from unexpected errors or malfunctions, which enhances overall system reliability. This capability is particularly important in safety-critical applications where failure to respond can lead to serious consequences. The other options, which may pertain to different functions in computer systems, do not describe the primary role of a watchdog timer, which is specifically designed for monitoring system responsiveness and aiding in recovery.