A3Lb And A4Lb Test Procedures; Smartjack Test Procedure; Addressable Repeater Loopback Commands (A3Lb And A4Lb); Smartjack Loopup And Loopdown Commands - ADC HiGain H2TU-R-402 List 5E Technical Practice

LTPH-TP-1047-01, Issue 1

A3LB and A4LB Test Procedures

The H2TU-C can be looped back by sending the Addressable Office Repeater (AOR) LPBK activation code
1111-1111-0001-1110 (FF1E) for at least 5 seconds. This causes the H2TU-R to enter the NLOC state. The
H2TU-C Loopback Time-Out (LBTO) setting determines the duration of this loopback unless it is overridden by
the reception of a second identical 16-bit loopup command before the timer expires. When this time-out override
state exists, the only way to loop the H2TU-R down is to issue one of the three loopdown commands listed in
Table 13. The automatic time-out mode is restored during subsequent loopback sessions.
Table 13 summarizes the codes required to execute Addressable 3 (A3LB) and Addressable 4 (A4LB) repeater
loopback commands. All code sequences must be present for at least 5 seconds.
Table 13. Addressable Repeater Loopback Commands (A3LB and A4LB)
Name Description
NLOC H2TU-R loopup from NI
CREM H2TU-R loopup from CI
NREM H2TU-R loopup from NI
CLOC H2TU-R loopup from CI
(a) The leftmost bit arrives first in all sequences. The detection algorithm functions reliably with a random 10
on the facility.

SmartJack Test Procedure

The HiGain H2TU-R supports the standard SmartJack loopback which can emulate a Network Interface Device
(NID) for the purpose of loopback testing of the HiGain HDSL2 circuit. SMJK and NREM loopbacks perform the
same functions, but their initiation differs. SMJK indicates that the loopback was initiated by any of the three
SmartJack loopup commands listed in
command or by a command issued from the maintenance terminal.
The SmartJack loopback option, LPBK, enables or disables the ability of the H2TU-R to emulate the family of
SmartJack loopback commands listed in
Inband 2-in-5 Inband 3-in-5
Loopup Code Loopdown Code
11000 11100
(a) These universal loopdown codes can release any and all existing loopup states regardless of loopback direction or method
of initiation. The codes are permanently enabled and independent of all loopback option settings, including the LPBK option.
SMJK loopbacks can only be activated by inband commands.
H2TU-R-402 List 5E
Table 14. NREM, on the other hand, is initiated by the 3-in-7 inband
Table 14.
Table 14. SmartJack Loopup and Loopdown Commands
Out-of-Band ESF FDL
(a)
Loopup Codes
1111-1111-0100- 1000 1111-1111-0100-1000 100000
March 12, 2001
Binary Code
1111-1111-0001-1110 (FF1E)
0011-1111-0001-1110 (3F1E)
1111-1111-0000-0010 (FF02)
0011-1111-0000-0010 (3F02)
Out-of-Band ESF FDL Inband 1-in-6
(a)
Loopdown Codes Loopup Code
Loopback Operation
(a)
(Hexadecimal Equivalent)
-3
Bit Error Ratio (BER)
Inband 1-in-3
(a)
Loopdown Code
100
33