Design Guide

I/O Subsystem

Intel

855GM/855GME Chipset Platform Design Guide 225

Table 95. LAN Design Guide Section Reference

Layout Section Figure 112 Reference Design Guide Section

Intel ICH4-M – LAN Connect Interface (LCI) A Reference Section 11.9.2

Intel 82562ET / Intel 82562EM B Reference Section 11.9.3

Intel 82551QM / Intel 82540EP C Reference Section 11.9.5

11.9.2. Intel

82801DBM ICH4-M – LAN Connect Interface Guidelines

This section contains guidelines on how to implement a Platform LAN Connect device on a system

motherboard. It should not be treated as a specification and the system designer must ensure through

simulations or other techniques that the system meets the specified timings. Special care must be given

to matching the LAN_CLK traces to those of the other signals, as shown below. The following are

guidelines for the ICH4-M to LAN Connect Interface. The following signal lines are used on this

interface:

• LAN_CLK

• LAN_RSTSYNC

• LAN_RXD[2:0]

• LAN_TXD[2:0]

This interface supports Intel 82562ET and Intel 82562EM components. Signal lines LAN_CLK,

LAN_RSTSYNC, LAN_RXD[0], and LAN_TXD[0] are shared by all components. The AC

characteristics for this interface are found in the Intel

82801DBM I/O Controller Hub 4 Mobile (ICH4-

M) Specification Update.