Measurement Computing CB-COM-7013 - Manual (Page 39)

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CB-7013, CB-7033 User’s Manual
3.3 Dual Watchdog Operation
Dual Watchdog = Module Watchdog + Host Watchdog
The Module Watchdog is a hardware reset circuit to
monitor the module’s operating status. While working in harsh or
noisy environment, the module may go down by the external noise
signal. The circuit may let the module to work continues and never
halt.
The Host Watchdog is a software function to monitor the
host’s operating status. Its purpose is to detect a network/communi-
cation problem or host halt. When a time-out occurs, the
module changes all outputs to the safe state to prevent
possible dangerous problems of a controlled unit/process.
The CB-7000 module with Dual W atchdog makes the
control system more reliable and stable.