Alcatel MainStreet 2902, Manual

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26 — System diagnostics
2902 MainStreet Technical Practices 26-7
May 2002 90-2906-01
A circuit remains in the busy-out state until it is changed by the operator to the
unbusy state or the system is restarted.
Procedure 26-7 To busy-out a circuit
where
p is 1 or 2, c is 1 to 31
pp is 1 or 9, c is 1, 2, A or B
* Default
26.6 Signaling leads
Digital circuits provide signaling information through signaling bits in the data
stream. Incoming signaling information indicates what is happening at the remote
end; outgoing signaling information transmits what is happening at the local end.
The 2902 MainStreet system allows you to examine incoming and outgoing
signaling leads. This troubleshooting tool provides a view of the far-end conditions
with which to determine, for example, whether a telephone is off-hook or what signal
patterns are being sent out. Outgoing signaling leads can be changed to force
conditions at the far end. For example, it may be useful to cause a DTU to lose
synchronization.
DNIC and 2B1Q signaling leads
For DNIC and 2B1Q incoming signaling leads, the Sync lead indicates whether or
not the DTU is synchronized. If the Sync lead is off, the DTU is not synchronized
and communication between the 2902 MainStreet system and the DTU is not
possible.
The LQ1 and LQ2 signals represent a two-bit binary number that indicates the
quality of the link (proportional to the margin of noise) between the 2902 MainStreet
system and the DTU. The higher the number, the higher the link quality.
For DNIC and 2B1Q outgoing signaling leads, when the Force Unsync lead is turned
on, the DTU loses synchronization. The DTU regains synchronization when the lead
is turned off.
Table 26-2 lists the incoming and outgoing signaling leads for the DNIC and 2B1Q
modules.
BUSY_OUT/UNBUSY*
MAINT — ON_CIRCUIT — <P p-c > or < pp-c >
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SK000539