Input/Output Interfaces

5.9Network Interface Controller

These systems provide 10/100/1000 Mbps network support through a Broadcom BCM5751 network interface controller (NIC), a PHY component, and a RJ-45 jack with integral status LEDs. The 82562-equivalent controller integrated into the 82801 ICH component is not used (disabled) in these systems. (Figure 5-14). The support firmware for the BCM5782 component is contained in the system (BIOS) ROM. The NIC can operate in half- or full-duplex modes, and provides auto-negotiation of both mode and speed. Half-duplex operation features an Intel-proprietary collision reduction mechanism while full-duplex operation follows the IEEE 802.3x flow control specification.

LED

Green Yellow

 

 

 

 

 

Green LED

 

 

 

RJ-45

 

 

 

 

 

 

 

 

 

 

 

 

Connector

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Broadcom

Tx/Rx Data

 

 

 

Tx/Rx Data

 

 

BCM5751

 

 

 

 

LAN I/F

 

 

 

 

 

 

 

 

 

 

 

 

 

NIC

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Yellow LED

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Function

Activity/Li nk. Indicates network activity and link pulse reception. Speed. Indicates link detection 100Mb/s mode.

Figure 5 14. Network Interface Controller Block Diagram

■The Network Interface Controller includes the following features:

■Dual high speed RISC controllers with 16-KB caches.

■Triple-mode support with auto-switching between 10BASE-T, 100BASE-TX, and 1000BASE-T.

■Power management support for ACPI 1.1, PXE 2.0, WOL, ASF 1.0, IPMI

■Cable testing capability

■Link and Activity LED indicator drivers

The controller features high and low priority queues and provides priority-packet processing for networks that can support that feature. The controller's micro-machine processes transmit and receive frames independently and concurrently. Receive runt (under-sized) frames are not passed on as faulty data but discarded by the controller, which also directly handles such errors as collision detection or data under-run.

The NIC uses 3.3 VDC auxiliary power, which allows the controller to support Wake-On-LAN (WOL) and Alert-On-LAN (AOL) functions while the main system is powered down.

✎For the features in the following paragraphs to function as described, the system unit must be plugged into a live AC outlet. Controlling unit power through a switchable power strip will, with the strip turned off, disable any wake, alert, or power mangement functionality.

5-36

361834-002

Technical Reference Guide