Lanner NCA-5520, User Manual

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Appendix E: Programming Generation 3 LAN Bypass
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APPENDIX E: PROGRAMMING GENERATION 3 LAN
BYPASS
The bypass function is used to link two independent Ethernet ports when the system crashes 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. Different from the previous two generations (Gen1 and Gen2), the Lanner
Bypass Gen 3 employs a programming method to control the bypass function by software. There are
typically two types of communication status for the bypass function, one is “
Normal “ and another is
“Bypass “ status. Furthermore, the Lanner Bypass software is capable of controlling the bypass status in the
following 3 instances.
When the system powers off, it can be forced to enable the LAN Bypass function.
When the system is in the just-on state which is a brief moment when it powers up.
The Lanner bypass possesses the following features:
1. Communication through SMBUS (I2C)
2. Independent bypass status control for each pair up to a total of 4 pairs
3. 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).
4. Software programmable bypass or normal mode
5. 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, with of 1~255 seconds of timer interval.
6. Multiple Watchdog Timers:
-
Two for run-time : It is designed to give you a more variety of controls of the bypass on port basis.
By using dedicated watchdogs for different pairs of bypass, you have the flexibility to manage the
bypass status for them differently.
-
One for just-on : It is designed to give you the precise control of the bypass during this phase. You
can use this timer to delay enabling the bypass in just-on state.
For a reference utility that contains sample code for LAN Bypass function programming, please visit
http://www.lannerinc.com/support/download-center/drivers, enter the product category and download
the utility package of this system.