Installation manual

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