User’s Manual
WIN Enterprises, Inc.
Sept., 2010
70
3. How to control LAN bypass function by GPIO during power on state
The bypass function can be enabled or disabled through Super I/O W83627EHG
GPIO1 during power on state. Below is the I/O port address and control bit.
Bypass Control Register
Logical Device 7, CR 30h
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
X X X X X
R/W
R/W
R/W
R/W: Read/Write, X: Not used
Bit [2:0]:
101 – Set bypass to disable when power on
010 – Set bypass to enable when power on
Please follow below steps to set the LAN bypass function control by GPIO.
(1). Set jumper JP6 to 1-2 to and bypass function can be controlled by GPI1.
(2). Refer to below program code and set LAN bypass enable or disable.
Bypass disabled when power on
===============================
MOV DX, 02EH
MOVAL, 07H
;Logic Device 7
OUT DX, AL
INC DX
OUT DX, AL
;select Logic device 7
DEC DX
MOV AL, 30H
OUT DX, AL
INC DX
MOV AL, 01H
OUT DX, AL
;Enable GPIO1
DEC DX
MOV AL, 0F1H
OUT DX, AL
INC DX
IN
AL, DX
;Read register F1 Data
