Advantech UNO-4672, Руководство пользователя

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61 Appendix C
C.2 Software Operation
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, the program must refresh the watchdog timer by rewrit-
ing the I/O port 443 (hex) while simultaneously setting it. When user
want to disable the watchdog timer, the program should read I/O port 443
(hex).
Table C.1: CN45 and SW4 Descriptions
Location Pin Status Description
CN45 1-2 Close DO7 is normal ( default )
2-3 Close DO7 link to 443 WDT output
SW4 DIP 1 On 443 WDT can reset the system
Off 443 WDT doesn’t link to reset pin (default)
DIP2 On 443 WDT can trigger the LED in the front
panel (WDT)
Off 443 WDT doesn’t link to LED (default)