MSI Keeper 945GM V1.0 - Manual (Page 32)

2-19
Hardware Setup
Lan Bypass function is controlled by GPIO 38 and 39.
For relay 1(LAN1 & LAN2), it ¦s defined by GPIO38, pull high to enable and pull
down to disable.
For relay 2(LAN3 & LAN4), it ¦s defined by GPIO39, pull high to enable and pull
down to disable.
Sample code:
mov si, offset MENUITEMGROUP:Lan_ByPass_Item
call X_GetItem_Value ;get BIOS item (LAN Bypass) value
or al,al ;base on this item value to
enable or disable this function
jz @f ;1 is enable, 0 is disable
mov dx,GPIO_Port + 38h
in al,dx
newiodelay
and al,not 11000000b
or al,11000000b ;GPIO 38, 39 pull high to enable
out dx,al
jmp short Exit_Lan_ByPass
@@:
mov dx,GPIO_Port + 38h
in al,dx
newiodelay
and al,not 11000000b ;GPIO 38, 39 pull down to disable
out dx,al
Exit_Lan_ByPass: