Aaeon SBC-598, Руководство пользователя

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70 SBC-598 User Manual
Programming the Watchdog Timer
If you decide to program the watchdog timer, you must write data
to I/O port 443 (hex). The output data is a value timer. The timer
ranges from 0 minutes (i.e., 00 hex) to 127 minutes 127 seconds
(i.e., FF hex).
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 write I/O port 80 (hex).
The following procedure is a sample program for the watchdog
timer:
•
Type C:\DOS\Debug <ENTER>
•
To start the watchdog timer and set function "Reset" type;
444 0 <ENTER>
out 444h data 0
•
To input the watchdog timer time-out interval of 3 min type;
443 83 <ENTER>
443 0 <ENTER>
out 443h data 83
•
To input the watchdog timer time-out interval of 5 sec type;
443 05 <ENTER>
out 443h data 05
•
To disable the watchdog timer type;
80 "x" <ENTER>
out 080h data "x" (where "x" can be any hex value)
The time interval data of the watchdog timer is shown in binary
code (8 bits).