ADTRAN HDSL2 - Manual (Page 72)

HDSL2 Loopback and Control Codes HDSL2 for General Distribution Installation and Maintenance Practice
A-4 61223HDSL2L2-5B
Loopback
Query D5D5
(1101 0101 1101 0101) (N) If unit is in loopback towards pattern, errors are
periodically injected toward pattern as long as pat-
tern is present.
H2TU-C 231 Errors every 20 seconds
HRE 10 Errors every 20 seconds.
H2TU-R 20 Errors every 10 seconds.
Loopback
Time Out
Override D5D6
(1101 0101 1101 0110) (N) If the units are armed and this pattern is sent, the
loopback time out is disabled. The time out option is
updated on the Provisioning menu of the H2TU-R to
“None” (viewable through the RS-232 port). As long
as the units remain armed, the time out remains
disabled. When the units are disarmed, the loopback
time out returns to the value it had before the D5D6
code was sent. As long as the pattern continues to be
sent, errors are injected again every 20 seconds as
follows:
H2TU-C 231 errors
H2TU-R 20 errors
Span
Power
Disable 6767
(0110 0111 0110 0111) (N) If the units are armed and this pattern is sent, the
H2TU-C deactivates the span power supply, turning
off the H2TU-R. As long as the pattern continues to
be sent, the span power supply remains disabled.
When the pattern is no longer being sent, the
H2TU-C reactivates the span power supply, turning
the remote unit(s) on. All units retrain and return to
the disarmed and unlooped state.
Table A-2. In-Band Addressable Loopback Codes (Continued)
(All codes listed below must be sent for a minimum of 5 seconds in order for them to be detected and acted upon.)
Function Code Source Code and Response