Advantech ADAM-5511 Manual page 115

The ADAM-5511 is equipped with a watchdog timer function that
resets the CPU or generates an interrupt if processing comes to a
standstill for any reason. This feature increases system reliability in
industrial standalone and unmanned environments.
If you decide to use the watchdog timer, you must write a function call
to enable it. When the watchdog timer is enabled, it must be cleared by
the application program at intervals of less than 1.6 seconds. If it is not
cleared at the required time intervals, it will activate and reset the CPU,
or generate a NMI (Non-Maskable Interrupt). You can use a function
call in your application program to clear the watchdog timer. At the end
of your program, you still need a function call to disable the watchdog
timer.
This section explains how to configure I/O module before applied into
ADAM-5511 system.
1. Open the ADAM-5511 package and make sure that the following
items are present:
(1) One ADAM-5511 main unit with two blank slot covers.
(2) One ADAM-5511 user's manual.
(3) One ADAM-5511 Windows Utility CD.
(4) One RS-232 DB-9 crossover cable for COM1 use.
(5) One straight through DB-9 cable for COM3 use
2. Set all the DIP switches off on ADAM-5511 back plant.