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MSI Keeper 945GM V1.0 User Manual

Page 34

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Hardware Setup

Watch Dog Function:

Support 1~255 second or minute selectable timeout interval.

Watch Code:

1) Enter configuration mode:

MOV DX,4EH

MOV AL,87H

OUT DX,AL

OUT DX,AL

2) Logical Device 8

MOV DX,4EH

MOV AL,07H

OUT DX,AL ;point to Logical Device Number Reg.

MOV DX,2FH

MOV AL,08H ;select Logical Device 8

OUT DX,AL

3) Enable WDTO# and set to KBRST#

MOV DX,2EH ;CR 30h: bit0 fill in 1

MOV AL,30H

OUT DX,AL

MOV DX,2FH

MOV AL,01H

OUT DX,AL

MOV DX,2EH ; CR F7h: bit4 fill in 0(clear event)

MOV AL,F7H

OUT DX,AL

MOV DX,2FH

IN DX,AL

AND AL,0F7H

OUT DX,AL

;CR F6h: bit0~7 fill in counter time

;CR F5h: bit1 fill in 1(Enable WDTO# & KBRST#)

Bit 3 (0: Second Mode,1:Minute Mode)

4) Exit configuration mode:

MOV DX,4EH

MOV AL,0AAH

OUT DX,,AL