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Watchdog timer configuration – Intel LGA775 User Manual

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INSTALLATIONS

Watchdog Timer Configuration

The WDT is used to generate a variety of output signals after a user
programmable count. The WDT is suitable for use in the prevention of
system lock-up, such as when software becomes trapped in a deadlock.
Under these sort of circumstances, the timer will count to zero and the
selected outputs will be driven. Under normal circumstance, the user will
restart the WDT at regular intervals before the timer counts to zero.

SAMPLE CODE:
This code and information is provided "as is" without warranty of any
kind, either expressed or implied, including but not limited to the
implied warranties of merchantability and/or fitness for a particular
purpose.

;[]================================================
; Name

: Enable_And_Set_Watchdog

; IN : AL - 1sec ~ 255sec
; OUT

: None

;[]================================================
Enable_And_Set_Watchdog Proc Near

push ax

;save time interval

call Unlock_Chip

mov cl, 2Bh
call Read_Reg

and al, NOT 10h

call Write_Reg

;set GP24 as WDTO

mov cl, 07h
mov al, 08h
call Write_Reg

;switch to LD8

mov cl, 0F5h
call Read_Reg

and al, NOT 08h
call Write_Reg

;set count mode as second

pop ax
mov cl, 0F6h
call Write_Reg

;set watchdog timer

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2801550 User’s Manual