I-7021/22/24, M-7022/24/28 User Manual, Rev: B2.3 179A.2 Dual Watchdog OperationDual Watchdog = Module Watchdog + Host WatchdogThe Module Watchdog is a hardware reset circuit thatmonitors the operating status of the module. Whileworking in harsh or noisy environments, the module maybe shut down by external signals. The circuit allows themodule to work continuously without disruption.The Host Watchdog is a software function that monitorsthe operating status of the host. Its purpose is to preventproblems due to network/communication errors or hostmalfunctions. When a host watchdog timeout occurs, themodule will reset all outputs to a safe state in order toprevent any erroneous operations of the controlled target.I-7000 and M-7000 series modules include an internalDual Watchdog, making the control system more reliableand stable.For more information regarding the Dual Watchdog,please refer to Chapter 5 of the “Getting Started ForI-7000 Series Modules” manual that can be downloadedfrom the ICP DAS website http://www.icpdas.com.
