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Accepting Call
Nx12 has accepted an incoming call and is waiting for the Telco switch to connect it.
Connected
All signaling is complete - the voice channel is available for use.
A caveat regarding the Ready indication: If you have this indication with the Nx12’s Telco mode
set to AT&T Cust and you cannot dial, it is likely that your line is Natl. I-1 or DMS-100. The
AT&T Custom PTP protocol does not require SPIDs, so the Nx12 does not send or check
them; it just assumes the line is OK in this regard, so it gives the ready indication, though the
line is actually waiting for the SPIDs.
Note
It is normal for Euro-ISDN ETS300 lines to go to the Deactivated state when not used. If
the system can dial normally under these circumstances, this indication is not a cause for
concern.
Is the problem only with one BRI circuit or does it move when you switch lines around?
If the problem remains with the line, then call your Telco. On the other hand, if a line that
works in one interface fails to work in another interface of the same Nx12 then you have an
problem with your ISDN interface card (or possibly elsewhere in the Nx12).
Are you using the Nx12’s internal NT1? (USA & Canada only)
The LED indicator of the status of the ISDN connection is on the rear panel near each of the
the U jacks. If the circuit is inactive, the LED will remain in the rapidly flashing state. This state
indicates a loss of the ISDN BRI circuit at the lowest (physical) level. Try another connecting
cable or another line.
If the NT1 can contact the central office, the LED will blink slowly (about 1 Hz). If the LED
remains in this state there is an internal ISDN problem or you could be connected to the wrong
jack on the back (Users in USA & Canada should be using the lower, RJ11 style jack). The LED
will come on solid when all handshaking is completed and the basic (low level) line connection
is good.
If the LED stays on, with the ISDN disconnected, or does not come on at all after cycling
power, there is a hardware problem.
Condition: Can’t Get ISDN Ready Indication
First try disconnecting the ISDN circuit(s) in question and waiting a full 60 seconds (leave the
Nx12 on) and then reconnect the circuit(s).
What kind of ISDN do you have, and is the Nx12 set to match it?
The telephone company should have given you the ISDN protocol when the line was ordered.
If you find yourself in the field without this information, it is usually possible to piece together
what you need.
If you are given SPIDs, you probably have Natl ISDN 1 or DMS 100 for your ISDN
♦
protocol. One SPID means one channel was activated, rather than the usual two.
No SPIDs and only one phone number generally means AT&T PTP protocol. You must
♦
not have SPIDs entered if using this protocol.
In Europe, you have either ETS300 (EuroISDN) or the local protocol, such as ITR6 in
♦
Germany or VN2 in France. The Nx12 only works with ETS300.
Summary of Contents for Nx12
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