Connectivity
26
ATM Media
Module LEDs
A further set of indicators appears on the ATM Media Module. Located on
the back panel of the AT-4016F, these LEDs convey diagnostic and status
information specific to the type of media connection that has been
installed. The location of these indicators is shown in Figure 22. A brief
discussion of their functions follows.
FAIL (Amber)—This LED indicates that the ATM Media Channel has
failed self-test or is disabled.
TIMING—(Green) This indicates the timing source of the ATM Media
Transmit (TX) signal. This source can be either INTERNAL or LOOP.
— INTERNAL—The TX signal timing is derived from an
internal time-base. The AT-4016F acts as the timing master.
— LOOP—The TX signal timing is derived from the Receive (RX)
signal timing. The AT-4016F acts as the timing slave.
SYNC (Green)—This LED indicates that the ATM Media Channel has
clock synchronization (bit-level).
LOS (Loss Of Signal) (Amber)—This indicates that the ATM Media
Channel is experiencing a Loss Of Signal on the Receive (RX) line The
problem may be caused by cables that are not installed correctly.
Figure 22: ATM Media Module
LEDs
