Specifications

Input/Output Controller Replacement Instructions 41
I/O Controller Connection Equipment and Port Signaling
Figure 25 MII Receptacle
Table 6 lists the pinouts and signals for the I/O controller MII receptacle.
Table 6 MII Receptacle Pinout
Fast Ethernet RJ-45 Connection Equipment
The RJ-45 receptacle on the I/O controller is configurable for 100 megabits per second (Mbps) and
supports IEEE 802.3, Ethernet, and IEEE 802.3u interfaces complaint with 10BASE-T and
100BASE-TX specifications.
The RJ-45 receptacle supports standard straight-through and crossover Category 5 UTP (RJ-45)
cables. (See Figure 24.) Cisco Systems does not supply Category 5 UTP cables; these cables are
available commercially.
Figure 26 shows the RJ-45 receptacle and plug. Table 7 lists the pinouts and signals for the RJ-45
receptacle.
Pin
1
1 Any pins not indicated are not used.
In Out I/O Description
14–17 – Yes – Transmit Data (TxD)
12 Yes – – Transmit Clock (Exactly)
2
2 Exactly and Rx_CLK are provided by the external transceiver.
11 – Yes – Transmit Error (Tx_ER)
13 – Yes – Transmit Enable (Tx_EN)
3 – Yes – MII Data Clock (MDC)
4–7 Yes – – Receive Data (RxD)
9 Yes – – Receive Clock (Rx_CLK)
10 Yes – – Receive Error (Rx_ER)
8 Yes – – Receive Data Valid (Rx_DV)
18 Yes – – Collision (COL)
19 Yes – – Carrier Sense (CRS)
2 – – Yes MII Data Input/Output (MDIO)
22–39 – – – Common (ground)
1, 20, 21,
40
– – – +5.0 volts (V)
Jackscrew Pin 21
Pin 1
H6538