3Com MSR 30, MSR 20, MSR 50 manual FIC-1AT3, LEDs on the FIC-1AE3 panel

186 CHAPTER 4: FLEXIBLE INTERFACE CARDS

Table 130 LEDs on the FIC-1AE3 panel

LED	Description
LINK	OFF means no link is present; ON
	means a link is present.
ACT	OFF means no data is being
	transmitted or received; blinking
	means data is being received or/and
	transmitted.

Interface Cable The interface that the FIC-1AE3 provides uses two SMB sockets for data transmitting and receiving respectively. The ports adopt the 75-ohm unbalanced transmission mode and are connected to the peer device using a pair of 75-ohm unbalanced coaxial cables. Several cable length options are available.

Figure 228 E3/T3 cable

BNC connector SMB connector

n The FIC-1AE3 and the FIC-1AT3 use the same type of cables for connection, which are called E3/T3 cables in this manual.

Connecting the Interface

Cable

c CAUTION: By design, the FIC-1AE3 is protected against lightning strikes. But when outdoor cabling is involved, you are recommended to add a special lightning arrester at the input end of the E3/T3 cable for better protection.

Step 1: Connect the SMB connector of an E3/T3 cable to the Tx port on the

FIC-1AE3 and another end to the Rx port on another device.

Step 2: Connect the SMB connector of another E3/T3 cable to the Rx port on the

FIC-1AE3 and another end to the Tx port on another device.

Step 3: Check the behavior of the LINK LED on the FIC-1AE3 panel: OFF means fault occurs on the line and the signal is out of synchronization. Check the line status.

FIC-1AT3

Introduction FIC-1AT3, the 1-port 44 Mbps ATM-T3 interface card, provides these functions:

■Two ATM cell mapping modes: ADM and PLCP.

■Scrambling in data transmission.

■Line clock (when working as DTE interface) and internal clock (when working as DCE interface).