Multi-Rate OCU DP Installation/Maintenance - Adtran

PRACTICES
1. GENERAL
1 Covered by INC patent number 4,862,480.
2 Covered by ADTRAN patent number 4,759,035.
C A U T I O N !
SUBJECT TO ELECTROSTATIC DAMAGE
OR DECREASE IN RELIABILITY.
HANDLING PRECAUTIONS REQUIRED.
ADTRAN MODEL MULTI-RATE OCU DP
ALL-RATE OFFICE CHANNEL UNIT DATAPORT
FOR NORTHERN TELECOM CHANNEL BANKS
INSTALLATION/MAINTENANCE
CONTENTS
1. GENERAL ...................................................................1
2. INSTALLATION...........................................................2
3. TESTING .....................................................................3
4. WARRANTY AND CUSTOMER SERVICE ................3
FIGURES
Figure 1. ADTRAN MULTI-RATE OCU DP........................1
Figure 2. Rate Selection Switches .....................................2
TABLES
Table A. AB Jumper ...........................................................2
Table B. Option Switch Settings .........................................2
Table C. Indicators .............................................................3
Table D. Latching Loopback Activation Sequence
(in order) ..............................................................4
Table E. Alternating Loopback Activation Sequence
(in order) ..............................................................4
The ADTRAN MULTI-RATE Office Channel Unit Dataport
with Digital Data Service Power (MULTI-RATE OCU
DP) unit is designed for use in the Northern Telecom DE-
3/4/4E PCM channel bank, and provides access to
Digital Data Service (DDS) or Basic Digital Service at all
standard rates. It provides the interface between the
pulse code modulation (PCM) bus of the T-carrier system
and the 4-wire loop extending to the customer premises.
Additionally, the unit may be used to power a midspan
DDS repeater or DDS termination unit. Figure 1 is an
illustration of the unit.
Features
Basic features of the MULTI-RATE OCU DP, part number
1410005L2, include:
• Subrate, 19.2 1 , 38.4, 56, and 64 kbps loop speeds,
including Secondary Channel
• Switched 56 (SW56) operating mode
• Extended loop range to 45 dB loss at all rates 2
• Loss of sealing current disconnect capability
• Poor loop quality disconnect capability
Section 61410005L2-5
Issue 1, November 1996
D4D14DJ1AA _ _
Figure 1. ADTRAN MULTI-RATE OCU DP
• Hardware or software A/B signaling detection for
Switched 56
• Bantam jack test access
• LED indicators for Loopback, Sealing Current, and
Abnormal Station Code.
The MULTI-RATE OCU DP occupies a single channel
position in the Northern Telecom DE-3/4/4E channel
bank and provides the interface between a DS-0 time
slot of the T-carrier datastream and the 4-wire metallic
loop extending to a midspan DDS repeater or the
customer premises. A customer-provided DSU/CSU
terminates the 4-wire loop; a DDS termination unit may
also reside on the customer’s premises to provide
loopback and test capability from the central office or
remote test system. The MULTI-RATE OCU DP may
interoperate over the carrier system with another OCU
DP, DS0 DP, DS-0 cross-connect system, or switch, and
may be located in an end office, hub office, intermediate
office, or remote digital terminal system.
61410.005L2-5A
Section 61410005L2-5, Issue 1
ADTRAN 1
Tx
Rx
OCU DP
1410005L2
OUT IN
SC
64
56
38.4
19.2
9.6
4.8
2.4
SW56
OCU LB
CHAN LB
NO SX
ASC
SW2
SW1
1 2 3 4 5 6
AB JUMPER

The MULTI-RATE OCU DP can be used as a replacement
for the Northern Telecom OCU DP 684C.
2. INSTALLATION
After unpacking the unit, immediately inspect it for
possible shipping damage. If damage is discovered, file
a claim immediately with the carrier, then contact
ADTRAN Customer Service, RMA; see subsection 4.
The MULTI-RATE OCU DP plugs directly into a Northern
Telecom DE-3/4/4E channel bank and requires no special
wiring or connections.
Optioning
The ADTRAN MULTI-RATE OCU DP is equipped with
two dual in-line package (DIP) switches, a jumper, and
a slide switch. See Figure 2, Table A, and Table B to
provision the unit.
Rate Selection
See Figure 1 for the
location of SW1 to set
the data rate of the unit.
Select the desired rate
by turning the appropriate
switch to the In
position. Only one rate
should be selected.
For Secondary
Channel operation,
select the SC switch
and the appropriate
rate switch by turning
both switches to the In
position. In SW56 or
64 modes of operation,
SC must not be
selected.
Figure 2. Rate Selection
Switches
AB Jumper
See Figure 1 for the location of the AB jumper. The AB
jumper must be positioned in accordance with the type
of backplane used in the channel bank. See Table A for
appropriate jumper positions.
Table A. AB Jumper
Function
Pins/Position
Select clock and power source
for the following:
DE-4 J7265AA-1 backplanes
DE-3 J7204AA-1 backplanes
DE-3 J7204AB-1 backplanes
DE-4E J7265AC-1 backplanes
DE-1000 J7510C-1 backplanes
OUTIN
1 2 3 4 5 6 7 8 9
P1, P2, P3
NOTE: DE-3/4 channel banks must be modified to
accept data units before the MULTI-RATE OCU
DP can be installed.
A
A
A
B
B
SC
64
56
38.4
19.2
9.6
4.8
2.4
SW56
SW2 Optioning
Table B provides provisioning information about the options
located on SW2. See Figure 1 for the location of SW2.
Table B. Option Switch Settings
Function
Switch/Description
Error Correction SW2-1 (ERROR CORRECTION)
On-Enables Error Correction
Off-Disables Error Correction
Zero Code SW2-2 (ZERO CODE SUPPRESSION)
Suppression On-Enables Zero Code Suppression
Off-Disables Zero Code Suppression
Latching SW2-3 (LATCHING LOOPBACK ENABLE)
Loopback On-Responds to latching loopback
sequences
Off-Ignores latching loopback sequences
AB Signaling
Quality Monitor
Extended
Transmit Range
SW2-4 (AB SIGNALING)
On-Enables hardware A/B bit detection
Off-Enables in-band A/B bit detection
SW2-5 (QUALITY MONITOR)
On-Enables AutoDisconnect feature
Off-Disables AutoDisconnect feature
SW2-6 (Extended Transmit Range)
On-Enables ETR
Off-Disables ETR
Error Correction
When error correction is enabled, the MULTI-RATE
OCU DP provides an error-detection and correction
capability that maintains data integrity across the carrier
facility. For subrate and 19.2 kbps rates, error correction
and data transmission can be accomplished over a
single DS-0 time slot. For rates of 38.4, 56, and 64 kbps,
error correction requires one DS-0 time slot for data
transmission and an additional DS-0 time slot for the
error-correcting parity byte. The parity byte resides in
the DS-0 time slot adjacent to and immediately following
the DS-0 time slot occupied by the data. For this reason,
the physical slot following the OCU DP must remain
vacant. For rates of 38.4 kbps and above, the MULTI-
RATE OCU DP optioned for error correction must not be
placed in channel bank slot 24.
Zero Code Suppression
When zero code suppression is enabled, the MULTI-
RATE OCU DP prevents a network byte consisting of all
zeros from entering the T-carrier datastream. On
alternate mark inversion (AMI) facilities, this function is
necessary to maintain the pulse density required for
synchronization. B8ZS-carrier facilities that
accommodate 64 kbps Clear Channel operation do not
require the zero code suppression function, and it is
automatically disabled when the 64 kbps rate has been
selected.
2 ADTRAN Section 61410005L2-5, Issue 1 61410.005L2-5A

Latching Loopback
When latching loopback is enabled, the Multi-Rate
OCU DP responds to OCU and CSU latching loopback
sequences appropriately. The OCU LB and CSU LB
indicators turn On following appropriate loopback
sequence.
AB Signaling
When AB Signaling is enabled, the MULTI-RATE OCU
DP determines the state of the A and B signaling bits
required for Switched 56 operation from the signals
present on the backplane of the channel bank. This
method assumes that tandems and cross-connects
between the MULTI-RATE OCU DP and the switch
have maintained the signaling bit positions through twostate
or four-state optioning. When AB Signaling is
disabled, the MULTI-RATE OCU DP derives signaling
bits from the incoming data of the DS-0 time slot.
This switch has no effect if the SW56 rate
option is not enabled on SW1.
Quality Monitor
When Quality Monitor is enabled, the MULTI-RATE
OCU DP monitors the incoming 4-wire loop data for the
presence of severe bit errors. In the presence of a
circuit disturbance, the MULTI-RATE OCU DP blocks
the transmission of errored data into the network by
substituting abnormal station code (ASC) bytes; upon
clearing of the troubled condition, the MULTI-RATE
OCU DP automatically restores data transmission. In
multipoint systems, this feature permits the remaining
branches to operate should one branch become
corrupted. The ASC indicator turns On upon blocking of
data; see Table C.
Extended Transmit Range
When Extended Transmit Range is enabled, the OCU
DP will automatically increase the transmitter output
level if the received signal level has been attenuated by
more than 34dB. The increase in output level provides
approximately 6dB of boost to the customer equipment,
aiding in signal recovery for marginal, extended range
circuits.
Table C. Indicators
Indicator Description
OCU LB
Turns On upon OCU loopback
activation
CHAN LB
Turns On upon CSU loopback
activation
NO SX
Turns On in the absence of loop
sealing current
Turns On for unterminated circuit
ASC
and upon Quality Monitor autodisconnect;
transmits Abnormal
Station Code to network
3. TESTING
The ADTRAN MULTI-RATE OCU DP may be tested
from a remote test system or through the faceplate
bantam jacks using a TPI 108/109RT or functionally
equivalent test set. The MULTI-RATE OCU DP responds
to latching and alternating sequences of OCU and CSU
loopback codes at all rates except 64 kbps.
If 64 kbps is selected and the latching loopback
option is enabled, the unit only responds to
latching loopback sequences; alternating
sequences are not valid at this rate.
Loopbacks
An OCU loopback causes a loopback to the network at
the point in the MULTI-RATE OCU DP closest to the 4wire
loop. The MULTI-RATE OCU DP responds to the
CSU loopback sequence by reversing the sealing current
direction on the 4-wire loop. Latching loopbacks permit
a higher level of data pattern sensitivity testing than is
afforded by the alternating loopback. The latching and
alternating loopback sequences are defined in Tables D
and E.
4. WARRANTY AND CUSTOMER SERVICE
ADTRAN will replace or repair this product within ten
years from the date of shipment, if the product does not
meet its published specifications or if it fails while in
service. For detailed warranty, repair, and return
information, refer to the ADTRAN Equipment Warranty
and Return Policy and Procedure.
Return Material Authorization (RMA) is required prior to
returning equipment to ADTRAN. ADTRAN does not
recommend that repairs be performed in the field.
For service, RMA requests, or further information, contact
one of the following numbers:
ADTRAN Customer Service:
RMA (Repair Service) (205) 971-8722
Technical Support (Post-Sales) (800) 726-8663
Applications Engineering
(Pre-Sales Support and Inquiries) (800) 615-1176
Sales (800) 827-0807
Repair and Return Address:
ADTRAN, Inc.
Customer Service Department
901 Explorer Boulevard
Huntsville, Alabama 35806-2807
61410.005L2-5A Section 61410005L2-5, Issue 1
ADTRAN 3

Function
Clear existing
loopbacks
Identify device
to be looped
Prepare
to loop;
send MAP
code after
30 bytes
Activate
loopback
Table D. Latching Loopback Activation
Sequence (in order)
Byte Code
Transition in
progress (TIP)
*0111010
Loopback select
code (LSC)
*1010101 - OCU
*0110001 - CSU
*1000001 - NI
Loopback
Enable (LBE)
*1010110
Far-End Voice
(FEV)
*1011010
# of Received
Bytes
Minimum of 35
TIP bytes
Minimum of 35
LSC bytes
Minimum of 100
LBE bytes
Minimum of 32
FEV bytes
Minimum of 35 TIP bytes required to disable established
latching loopback.
* - Don't Care bit
Table E. Alternating Loopback Activation
Sequence (in order)
Function
Activate loopback
Maintain loopback and
test for bit errors
Clear loopback
* - Don't Care bit D - data bit
Received Bytes
Four consecutive bytes of
specified loopback code
*0101010 - OCU
*0101000 - CSU
*0101100 - DSU
Data byte alternating with
loopback code
example:
*DDDDDD1/*0101010
Four consecutive data bytes
4 ADTRAN Section 61410005L2-5, Issue 1 61410.005L2-5A