PairGain T1L2PY0AA, Manual

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Troubleshooting 150-231-181-01, Revision 01
44 September 7, 1999 HLU-231 List 8A
Table 13. Summary of HiGain Loopback Codes
Method of Transmission
Loopback Code Description Test Set Craft Port MODE/SEL
NLOC 1111000
4-in-7
Network Local. Invokes HLU loopback toward the network.
X X X
NDU1 110000
2-in-6
Network Doubler 1. Invokes HDU1 loopback toward the
network.
X X X
NDU2 111000
3-in-6
Network Doubler 2. Invokes HDU2 loopback toward the
network.
X X X
NDU3 1010001 Network Doubler 3. Invokes HDU3 loopback toward the
network.
X X X
NDU4 1010010 Network Doubler 4. Invokes HDU4 loopback toward the
network.
X X X
NREM 1110000
3-in-7
Network Remote. Invokes HRU loopback towards the
network.
X X X
CLOC 1111100
5-in-7
Customer Local. Invokes HRU loopback towards the
customer.
X X X
CDU1 111100
4-in-6
Customer Doubler 1. Invokes HDU1 loopback towards the
customer.
X X X
CDU2 111110
5-in-6
Customer Doubler 2. Invokes HDU2 loopback towards the
customer.
X X X
CDU3 1011001 Customer Doubler 3. Invokes HDU3 loopback towards the
customer.
X X X
CDU4 1011010 Customer Doubler 4. Invokes HDU4 loopback towards the
customer.
X X X
CREM 1111110
6-in-7
Customer Remote. Invokes HLU loopback towards the
customer.
X X X
SMJK LpUp
(PL)
11000
2-in-5
SmartJack Loopup or NID payload (PL) code. Invokes
HRU loopback towards network.
X
SMJK LpUp
(ESF-DL)
1111-1111-
0100-1000 SmartJack Loopup or NID (ESF-DL) code. Invokes HRU
loopback towards network.
X
SMJK LpDn
(PL)
11100
3-in-5
SmartJack Loopdown or NID payload (PL) code. Removes
SMJK, NLOC, NREM, CREM, CLOC, CDUn, and NDUn.
X
SMJK LpDn
(ESF-DL)
1111-1111-
0010-0100 SmartJack Loopdown or NID (ESF-DL) code. Removes
SMJK, NLOC, NREM, CREM, CLOC, CDUn, and NDUn.
X
HiGain systems feature the SmartJack option, which can emulate a Network Interface Device
(NID) for the purpose of loopback testing of the HiGain circuit. SMJK and NREM loopbacks
perform the same functions but their initiation differs. SMJK indicates that the loopback was
initiated by the 2-in-5 inband command. NREM, on the other hand, is initiated by the 3-in-7
inband command or by a command issued from the maintenance terminal or the MODE and SEL
buttons.
Use the inband commands to enable or disable the SMJK loopback options. (Pressing the
remote loopback button will also loopdown the SmartJack loopback.) The HLU system setting
is normally enabled to recognize all inband SmartJack loopback commands.