Remote System Alert Support; Figure 5-13. Remote Sensea - Compaq Deskpro EXS Technical Reference Manual

5.9.3 REMOTE SYSTEM ALERT SUPPORT

These systems provide Remote System Alert (RSA) support for such NIC cards as the 3Com
3C905C-TX NIC card. The RSA function is similar to AOL in that the unit provides, even while
powered off, system status alert messages to a network console. However, NIC cards implementing
the RSA method do not use the SMBus for receiving alert information and therefore require, in
addition to the PCI connection, an auxiliary AOL/SOS cable connection with the system board
(Figure 5-13).
Network
Cable
System Board
Figure 5-13. Remote Sense Alert Implementation (Generic Representation)
In the Remote Sense Alert implementation, a NIC card receives event notification directly from the
system's thermal sensors and the LPC47B357 I/O controller over an AOL/SOS cable connection
(Figure 5-14). During system-off conditions the NIC card receives auxiliary power from the 3.3
VDC auxiliary power rail on the PCI bus.
Figure 5-14. RSA Logic, Block Diagram
NIC Card in PCI Slot
System Board
BIOS Fail
47B357
OS Fail
I/O Cntlr.
NC
Intrusion
NC
Fan Alert
NC
Pwr Alert
NC
Thermal
Thermal
ASIC
PCI
Bus
Compaq Deskpro EXS and Workstation 300 Personal Computers
First Edition - December 2000
Technical Reference Guide
AOL/SOS Cable
NIC Card
AOL/SOS
Header
SOS
1
7
PCI
Connector
Featuring the Intel Pentium 4 Processor
AOL/SOS
Header P12
PCI
Bus
5-35