User’s Manual
Custom Embedded Solutions
WIN Enterprises, Inc. [email protected] www-win-ent.com (978)688-2000
75
4. How to control Segment 1 & 2 LAN bypass function by GPIO during power
off state
The power off bypass function can be enabled or disabled through W83627EHG
GPO30 ~33. Below is the I/O port address and control bit.
Power off State Bypass Control Status Register
Logical device 9, CRF1
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
X
X
X
X
R/W
R/W
R/W
R/W
R/W: Read/Write, X: Not used
Bit [1:0]
01 - Set segment 1 bypass to enable when power off
10 - Set segment 1 bypass to disable when power off
Bit [3:2]
01 - Set segment 2 bypass to enable when power off
10 - Set segment 2 bypass to disable when power off
Refer to below program code and set segment 1 & 2 LAN ports to bypass state or disable
when power is off.
Segment 1: Control by CRF1 bit 1 & 0
Bypass disabled when power off
;---------------------------------------------------------------------------------
;Enter the extended function mode, interruptible double-write
;---------------------------------------------------------------------------------
MOV DX, 87H
;address
MOV AL, 2EH
;Index
OUT DX, AL
;enter super IO
OUT DX, AL
;enter super IO
;------------------------------------------------------------------------------------
; Configure logical device 9
;------------------------------------------------------------------------------------
