16
Programming LAN Bypass
Appendix D
Network Application Platforms
Appendix D:
Programming LAN Bypass
The bypass function is used to link two independent
Ethernet ports when the system crash or powers off.
This means if your system is equipped with a LAN Bypass
function, a condition in your system will not interrupt your
network traffic. There are typically two communication
status for the bypass function, one is “Normal” and another
is “Bypass”. Lanner provides software for controlling the
LAN Bypass function:
Lanner ‘s Bypass Modules include WDT (Watch Dog Timer)
controller and Bypass switch.
Our Bypass Modules also include a software development
kit that enables system designer to efficiently design
systems to support bypass functionality. Lanner Bypass
Modules with watchdog control have the following
features:
Communication through SMBUS (I2C)
•
Independent bypass status control for each pair up to
•
a total of 4 pairs
Lanner Bypass Modules can bypass systems Ethernet
•
ports on a host system during three instances: Just-on
(Just-on is the brief moment when the internal power
supply turns on and booting process starts), system
off, or upon software request (during run-time).
Software programmable bypass or normal mode
•
Software programmable timer interval:
•
- JUST-ON watchdog timer, used during JUST-ON, has
timer setting of 5~1275 seconds of timer interval.
- Run-Time watchdog timer, used during run-time, has
setting of 1~255 seconds of timer interval.
Please refer to the
Lanner Bypass Watchdog module-
User Guide
in the LAN_Bypass_Watchdog folder for
implementation guidance.
For sample LAN bypass code, see the
LAN_Bypass_
Watchdog
folder on the
Driver and Manual CD
.
Fro a description of the physical LAN ports equipped with
this function, refer to
Front Panel Features
in
Chapter 1
