Appendix1 Dual Watchdog Operation - ICP DAS USA I-87211W User Manual

I-87211W User Manual

Appendix1 Dual Watchdog Operation

Dual WatchDog = Module Watchdog + Host WatchDog
The Module Watchdog is a hardware reset circuit that monitors the
operating status of the module. While working in harsh or noisy
environments, the module may be shut down by external signals.
The circuit allows the module to work continuously without
disruption.
The Host WatchDog is a software function that monitors the
operating status of the host. Its purpose is to prevent problems due
to network/communication errors or host malfunctions. When a
Host WatchDog timeout occurs, the module will reset all outputs to
a safe state in order to prevent any erroneous operations of the
controlled target.
I-7000 and M-7000 series modules include an internal Dual
Watchdog, making the control system more reliable and stable.
For more information regarding the Dual WatchDog system, please
refer to Chapter 5 of the "Getting Started For I-7000 Series
Modules" manual that can be downloaded from the ICP DAS
website http://www.icpdas.com.
93/93 I-87211W User Manual V2.5, Oct. 2010