Total Access 1500 Total Reach DDS-DP Installation and Maintenance Guide
10
61180105L1-5C
NOTE
A
minimum
of
35
TIP
bytes
is
required
to
disable
established
latching
loopback.
X
=
Don
ʹ
t
Care
bit.
A/B Signaling (A/B)
When
A/B
Signaling
(
SW1-4
)
is
OFF,
the
unit
derives
signaling
from
the
incoming
data
stream.
When
A/B
Signaling
is
ON,
the
unit
determines
the
state
of
the
A
and
B
Signaling
bits
using
signals
present
on
the
backplane
of
the
channel
bank.
This
method
assumes
that
proper
signaling
has
been
maintained
throughout
network
tandems
and
cross
connect
systems.
NOTE
A/B
Signaling
option
is
only
applicable
when
SW56
is
selected;
otherwise
it
is
a
“don’t
care.”
Quality Monitor (QM)
When
Quality
Monitor
(
SW1-5
)
is
ON,
the
TR
DDS
‐
DP
monitors
the
incoming
2
‐
wireloop
and
4
‐
wire
customer
interface
data
for
errors.
If
excessive
errors
are
detected,
the
unit
blocks
the
customer’s
data
transmission
and
transmits
an
alternating
MOS
(9Ah)/ASC
(9Eh)
trouble
code
to
the
network.
Customer
data
transmission
is
automatically
restored
when
the
trouble
condition
is
cleared.
Rate Selection
Select
rate
with
dip
switch
(
SW4
)
by
positioning
the
selected
switch
toward
the
inscribed
rate.
NOTE
Select
only
one
rate.
More
than
one,
or
none,
defaults
to
56
kbps
without
secondary
channel.
NOTE
If
either
SW56
or
64
kbps
is
selected,
the
secondary
channel
(SC)
switch
should
not
be
selected.
