Advantech PCM-9570/S 2006957006 5th Edition - Manual (Page 90)

78 PCM-9570/S User's Manual
A.1 Programming the watchdog timer
In order to program the watchdog timer, you must write a program
which writes I/O port address 443 (hex). The output data is a value of
time interval. The value range is from 01(hex) to 3E(hex), and the
related time interval is 1 sec. to 62 sec.
Data Time Interval
01 1 sec.
02 2 sec.
03 3 sec.
04 4 sec.
.
.
.
3E 62 sec.
After data entry, your program must refresh the watchdog timer by
rewriting the I/O port 443 (hex) while simultaneously setting it.
When you want to disable the watchdog timer, your program should
read I/O port 443 (hex).