Cisco AGS+, Hardware Installation And Maintenance

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Applique
LED
Indicators
The
Receive
Timing
RT
and
Send Timing
ST
LEDs
indicate
that
clock
signal
is present inside
the
APP-LHS
transmitter
and
receiver
The
clock
source
is
external during
normal
operation
and
internal
during
loopback
DCE
Available
CA
indicates
that the
DCE
data service unit
DSU
is
prepared to
send
and
receive
data
to
and from
the
DTE
DTE
Available
TA
indicates the
DTE
is prepared to
send
and
receive
data
to
and from
the
DCE
DSU
Data
transmission can
begin
only
after
both
CA
and
TA
have been
asserted
Loopback
circuit
LA
Loopback Circuit
LB
and Loopback
Circuit
LC
are
software-controlled
functions
When
lit
LA
LB LC
and
Loopback Internal
LI
indicate
that
the
system
is
in an internal or external loopback
diagnostic
mode
These
loopbacks
enable the system
diagnostics to
verify the
links
between
the
DTE
and
DCE
LA
and LB
are
sent
from
the
DTE
to
request loopbacks
in
the
DSU
LC
is
sent
by
the
DCE
DSU
to request loopbacks
from
the
DTE
by
default
LC
is
inhibited
by software
If the
DSU
supports
LC
you must
enable
it
with
the
hssi external-loop-request
configuration
command
before
it
can be
used
If
LC
is
not used
it
should
remain
disabled
to
avoid noise on
the
LC
line
To
disable
LC
use
the
no hssi external-loop-request
configuration
command
Refer
to
the
appropriate
optional
software
publication
for more
information on
using these configuration
commands
The
green
OK
indicator
lights
after
the software has
performed
its
startup
verification
The
red
ribbon cable error
ER
indicator
lights
when
the internal
ribbon
cable
which
is
located
between
the
HSCI
system
card and
the
APP-LHS
applique is installed
incorrectly
B-12
AGS
Hardware
Installation
and Maintenance