Справочник Пользователя для Advantech PCI-6872
PCI-6872 User’s Manual
88
Appendix A Programming the Watchdog
Timer
A.1 Supported Input Timing Modes
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 inter-
val. The value range is from 01 (hex) to 3E (hex), and the related time
interval is 1 sec. to 62 sec.
writes I/O port address 443 (hex). The output data is a value of time inter-
val. 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.
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.
.
.
.
.
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).
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).
The following example shows how you might program the watchdog
timer in BASIC:
timer in BASIC:
10
REM Watchdog timer example program
20
OUT &H443, data REM Start and restart the
watchdog
30
GOSUB 1000 REM Your application task #1
40
OUT &H443, data REM Reset the timer
50
GOSUB 2000 REM Your application task #2
60
OUT &H443, data REM Reset the timer
70
X=INP (&H443) REM Disable the watchdog timer
80
END
1000
REM Subroutine #1, your application task
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