Nortel Enterprise 1000 Reference Manual page 150

Page 150 of 236
553-3023-211 Standard 1.00 June 2001
NTAK10 2.0 Mb DTI card
CEPT interface
For the Conference of European Postal Communications (CEPT) interface,
the connection to the external digital carrier is through the NT5K85 DTI cable
assembly. It converts the 120 ohms D-connector to 75 ohms coaxial cable.
The impedance is switch set. The switch-settings table at the end of this
chapter describes the options. See Table 35 "Switch settings" on page 153.
If a coaxial interface is required, use NT5K85 in conjunction with the
NTBK05.
Channel associated signaling
Channel associated signaling means that each traffic carrying channel has its
own signaling channel permanently associated with it. Timeslot 16 is used to
transmit two types of signaling: supervisory and address.
Incoming signal
Functions of the NTAK10 with regard to incoming signaling include:
• recognizing valid changes
• determining which channels made the changes
• collecting PPM
• reporting changes to software
Outgoing supervisory signals
The desired ABCD bit pattern for a channel is output by the NTAK10, under
the control of the system controller card. The bit pattern to be transmitted is
held on the line for a minimum period of time. This time is specified in the
same message and ensures that the signal is detected correctly at the far end.
With the exception of the outpulsing signals and special signals, such as
Denmark's Flash signal and Sweden's Parking signal, the minimum duration
of any signal state is 100 ms. Some signal states can have a minimum duration
time that is longer than 100 ms.
Periodic Pulse Metering
Periodic Pulse Monitoring (PPM) is used to collect toll charges on outgoing
CO trunk calls.