User’s Manual
WIN Enterprises, Inc.
Sept., 2010
72
4. How to control LAN bypass function by GPIO during power off state
The power off bypass function can be enabled or disabled through W83627EHG
GPIO1. 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 off
110 – Set bypass to enable when power off
Refer to below program code and set LAN bypass enable or disable when power off.
Bypass disabled when power off
===============================
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
AND AL, 11111000B
;Mask Bit 0 1 2 to use Bypass
