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Appendix a: programming watchdog timer, Appendix a, Programming watchdog timer – Lanner FW-7540 User Manual

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Programming Watchdog Timer

Network Application Platforms

Appendix A

Appendix A:

Programming Watchdog

Timer

A watchdog timer is a piece of hardware that can be

used to automatically detect system anomalies and reset

the processor in case there are any problems. Generally

speaking, a watchdog timer is based on a counter that

counts down from an initial value to zero. The software

selects the counter’s initial value and periodically restarts

it. Should the counter reach zero before the software

restarts it, the software is presumed to be malfunctioning

and the processor’s reset signal is asserted. Thus, the

processor will be restarted as if a human operator had

cycled the power.
For sample watchdog code, see watchdog folder on the

Driver and Manual CD

For sample watchdog code, see watchdog folder on the

Driver and Manual CD