22
•
Bypass and WDT
5.1.2
Communication States
There are two comm unications states for the bypass function: (1)
Normal State
, (2)
Bypass State
. A watch-dog-timer (WDT) is used to
control and switch the communication between the two states. A relay
array is controlled by the WDT for physically routing of the two Ethernet
ports.
The block diagram in the section 5.1.1 shows the
Normal State
, where
the two Ethernet ports work independently. The following diagram
shows the
Bypass State
, where the two Ethernet ports are bypassed
together.
Bypass State
Relays are "Dis-energized".
82559
Ethemet #1
82559
Ethernet #2
Bypass
Relays
WDT
Relay
Driver
Intel 21154
PCI-to-PCI
bridge chip
( 64 or 32-bit )
GPIO0
GPIO1
GPIO2
GPIO3
SW1
JP4~7
Time out value
Power on default
PCI BUS
32-bit
32-bit
32-bit
or
64-bit
PCI Slot
5.1.3
WDT Test Utilities
Before programming this card, users can evaluate the functionality by
using the DOS test utilities which in the ADLINK CD. Please refer the
section 5.3 for list of the functions. The following section also explains
how to use those utilities to change the communication states.
5.1.4
WDT and State Change
This section shows the flow how software and WDT control the state
change. The power on status can be choose as either
Bypass State
or
Normal State
by jumper JP4~7.
Summary of Contents for PCI-8213
Page 1: ...PCI 8213 8214 4 Port 2 Port PCI Ethernet Controller User s Guide Recycled Paper...
Page 2: ......
Page 8: ......
