Intel SYS7180VE - Manual (Page 33)

CHAPTER 3 - BIOS SETUP
SYS7180VE User’s Manual 59
APPENDIX Watch-Dog-Timer (WDT) Setting
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
Test procedure in DOS
Implement Debug order in MS-DOS:
o ef f1
o ef 5
[ enter]
The system will reset after 5 seconds
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
CHAPTER 3 - BIOS SETUP
60 SYS7180VE User’s Manual
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.