Setting - Intel SYS7180VE User Manual

APPENDIX
Watch-Dog-Timer (WDT) Setting
一． Definition for SYS7180VE watchdog
The watchdog timer can be adjusted by software setting from
1second to 239seconds or from 1 minute to 239 minutes. The I/O port is
defined at address EFH. You can trigger/enable disable the timer by
writing port EFH.
F0H: timer for minute
F1H: timer for second
0: disable the timer
二． Test procedure in DOS
Implement Debug order in MS-DOS:
o ef f1
o ef 5
[ enter]
The system will reset after 5 seconds
三． Assembly language example
Timer for second:
mov AL, f1
mov dx, ef
out dx, AL
mov AL, 65 (time for 65 sec. decimal system )
mov dx, ef
out dx, AL
Timer for minute:
mov AL, f0
mov dx, ef
out dx, AL
mov AL, 75 (time for 75 min. decimal system )
mov dx, ef
out dx, AL
Disable the watchdog-timer:
mov AL, 0
mov dx, ef
out dx, AL
SYS7180VE
User's Manual
CHAPTER 3 - BIOS SETUP
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CHAPTER 3 - BIOS SETUP
NOTE: Because WIN NT，win2000，win2003，winXP are not effective by
writing the port directly, so we must make lib file、driver or DLL first.
60 SYS7180VE
User's Manual