MSI Keeper 945GM V1.0 - Manual (Page 33)

M S-9641 M ainboard
2-20
By Pass Function:
LAN Bypass Normal
GPIO38 "High" " Low"
GPIO39 "High" " Low"
Lan Bypass function is controlled by GPIO 38 and 39.
For relay 1(LAN1 & LAN2), it ’s defined by GPIO38, set “Low” to enable and set
“High” to disable.
For relay 2(LAN3 & LAN4), it ’s defined by GPIO39, set “Low¨ to enable and set
“High¨ to disable.
Set “High¨ sample code :
mov dx,GPIO_Port + 38h ;GPIO_Port is 480h
in al,dx
newiodelay
or al,11000000b ;GPIO 38, 39 pull high to enable
out dx,al
Set “Low” sample code :
mov dx,GPIO_Port + 38h ;GPIO_Port is 480h
in al,dx
newiodelay
and al,not 11000000b ;GPIO 38, 39 pull down to disable
out dx,al
LAN5, LAN6 have no by pass function.