Intel 21143 manual 3.2.3 100-Ready External Module Design, 3.2.5 MII/SYM Pin Listing, Design Guide

Intel® 21143 PCI/CardBus 10/100Mb/s Ethernet LAN Controller

3.2.3100-Ready External Module Design

Figure 7 shows a block diagram of a 100-Ready design using an external module.

Figure 7. 10BASE-T 100-Ready External Module Block Diagram

21143	MII/SYM	MII or	MII or	10/100	RJ45
		Custom	Custom
				PHY Layer	Connector
		Connector	Connector
	10BASE-T	RJ45
		Connector
	Optional	AUI
	AUI Coaxial	Coaxial
	Transceivers	Connector
PCI
Bus
					LJ-05188.AI4

3.2.4Description of 100-Ready External Module Block Diagram

The blocks in the100-Ready external module block diagram represent the following components:

•21143 — A 21143 with all of the external components for operating the network connection (reference parts, XTAL, and so on). The 21143 can use the PCI bus, and the MII/SYM, 10BASE-T, and AUI coaxial ports for communication.

•Optional external MII/SYM daughtercard — A daughtercard with a 100 Mb/s or 10/100 Mb/s PHY that interfaces with an MII connector or custom connector. The daughtercard uses the magnetics to connect to the RJ45 connector.

•MII connector — An MII or custom connector that connects with the MII/SYM port of the 21143.

•RJ45 — A network connection.

3.2.5MII/SYM Pin Listing

Table 7 describes the MII/SYM pin multiplexing enabling the full flexibility for both network connections options using the same internal connector for the MII-based or the SYM-based PHY device (for detailed implementation notes, refer to the specific PHY device section in this document).

Table 7. MII/SYM Pinout (Sheet 1 of 2)

Pin Number	MII Interface Function	SYM Interface Function
117	mii_crs	sd
118	mii_clsn	sym_rxd<4>
119	mi_txd<3>	sym_txd<3>
120	mi_txd<2>	sym_txd<2>
121	mi_txd<1>	sym_txd<1>

14 Design Guide