DFI BT253 - Appendix A - Watchdog Sample Code

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Appendix A Watchdog Sample Code
Appendix A
Appendix A - Watchdog Sample Code
;Software programming example:
;---------------------------------------------
;(1) Enter Super IO Con f guration mode
;---------------------------------------------
MOV DX,4EH
MOV AL,87H
OUT DX,AL
OUT DX,AL
;-------------------------------------------------------------------------------------------
;(2) Con f guration Logical Device 8, register CRF0/CRF1 (WD T Control/WD T
timer)
;-------------------------------------------------------------------------------------------
MOV DX,4EH
MOV AL,07H ;Ready to Progr am Logical Device
OUT DX,AL
MOV DX,4FH
MOV AL,08H ;Select Logical Device 8
OUT DX,AL
MOV DX,4EH
MOV AL, F1H ;Select watchdog timer register
OUT DX,AL
MOV DX,4FH
MOV AL,10H ;Set watchdog timer value
OUT DX,AL
MOV DX,4EH
MOV AL, F0H ;Select watchdog Control R egister
OUT DX,AL
MOV DX,4FH
MOV AL,02H ;Set Watchdog Control Value
OUT DX,AL
;----------------------------------------------------------------
;(1) Exit extended f unction mode
;----------------------------------------------------------------
MOV DX,4EH
MOV AL,AAH
OUT DX,AL