Compaq W4000 Manual De Usuario

Chapter 5  Input/Output Interfaces 

 

 
These systems include a 10/100 Mbps network interface controller (NIC) consisting of a 82562-
equivalent controller integrated into the 82801BA ICH2 component coupled with a physical 
interface (PHY) component and an RJ-45 jack with integral status LEDs (Figure 5-14). The 
support firmware 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. Transmit and receive FIFOs of 3 kilobytes each 
reduce the chance of overrun while waiting for bus access.  
 
 

TX/RX

 

Network 

Interface 
Function

 

LAN 

PHY 

I/F

 

Speed 

(Yellow)

 

Active/ 

Link 

(Green)

 

82801 ICH2

 

TX/RX

 

RJ-45  

Connector

 

 
 
 
 
 
 
 
 

 
 

LED Function 
Green Activity/Link: 

Indicates 

network activity and link pulse 

reception. 

Yellow 

Speed: Indicates link detection in 100 MB/s mode 
(always on if 100Base-Tx is forced). 

 
 

Figure 5-13.   Network Interface Controller Block Diagram 

 

 
The Network Interface Controller includes the following features: 
 
♦  Fast Ethernet controller with 32-bit architecture and 3-KB TX/RX buffers. 
♦  Dual-mode support with auto-switching between 10BASE-T and 100BASE-TX. 
♦  Power down and Wake up support in both APM and ACPI environments (PME- and WOL). 
♦  Alert-on-LAN (AOL v1.0) support. 
♦  Link and Activity LED indicator drivers 
♦  AOL support for upgrade card  

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. 

5-32   Compaq Evo and Workstation Personal Computers 
          Featuring the Intel Pentium 4 Processor