ADTRAN T200 H2TU-R Installation And Maintenance Manual page 22

The disarming process ensures race-free operation of
HDSL2 element disarming and Smartjack loop down.
Duration of the disarm sequence may need to exceed
16 repetitions to allow detection and loop down of up
to three HDSL2 elements and the Smartjack. This
sequence will loop down the Smartjack and the
HDSL2 element.
All HDSL2 elements will automatically move from
the armed state into the disarmed state when a default
time out value of 2 hours is reached.
Arming Time Out ....................... 2 Hours
Overriding Loopback Time Out:
If the units are armed and this pattern is sent, the
loopback time out will be disabled. The time out
option will be updated on the Provisioning Menu of
the HTU-R (viewable through the RS-232 port) to
"None". As long as the units remain armed, the time
out will remain disabled. When the units are
disarmed, the loopback time out will return to the
value it had before the D5D6 code was sent.
Loopback Time Out Override .... 1101 0101 1101 0110
Disabling Span Power:
If the units are armed and this pattern is sent, the
HTU-C will deactivate its span power supply, turning
off the HTU-R and HRE (if present). As long as the
pattern continues to be sent, the span power supply
will remain disabled. When the pattern is no longer
being sent, the HTU-C will reactivate its span power
supply, turning the remote unit(s) on. All units will
retrain and return to the disarmed and unlooped state.
Span Power Disable ................. 1101 0101 1101 0110
In the Loop Up State, the selected HDSL2 element
provides continuous loop up of the DS1 signal.
However, the data flow is monitored for the in-band
deactivation sequence, the in-band disarming
sequence, and the ESF data link disarming sequence.
Also, a loop up time out value causes automatic return
to the armed state. All other control code sequences
are ignored in the loop up state.
A-4
Transition from Loop Up to Armed State: Any
HDSL2 element can be commanded to move from the
loop-up state into the armed state by a single in-band
16-bit deactivate control code sequence. The same
deactivation sequence as shown is used for all HDSL2
elements.
Deactivation Sequence ............ 1001 0011 1001 0011
An HDSL2 element must loop down after receiving
this deactivation sequence for at least 5 seconds.
Deactivation After Receiving Sequence for > 5 seconds
Duration of the deactivation sequence may need to
exceed 18 seconds to allow detection and loop down
of up to three HDSL2 elements. The deactivation
sequence does not disarm the HDSL2 elements. They
can still respond to activation sequence control codes.
All HDSL2 elements automatically move from the
loop up state into the armed state when the selected
loop up time out value is reached.
Loop Up Time Out ........ programmable from the
Transition from Loop Up to Disarmed State: All
HDSL2 elements can be simultaneously commanded
to move from the loop up state into the disarmed state
by either the standard 5-bit in-band disarming
sequence used for NIU Smartjack loop down, or by
the ESF DATA LINK command, as described in
Transition from Armed to Disarmed State.
Section 61222024L6-5, Issue 1
H2TU-C at None, 20, 60, or
120 minutes
61222024L6-5A