Nortel Networks Circuit Card Benutzerhandbuch

 NT8D14 Universal Trunk card

Trunk members are provisioned in the Trunk Data Block LD 14.

Refer to “Programming RAN trunks” on 

 and to Software Input/

Output: Administration (553-3001-311) for instructions on service change 
programs.

In the continuous operation mode (sometimes called the Audichron mode), a 
message is constantly played, over and over again. Callers “barge in” on a 
playing message or receive a ringback tone until the message plays again. The 
start line (ST+) is hardwired as always active. See Figure 139 on 

At the end of each message, a pulse is issued on the “C” line that is used by 
the trunk unit to cut through to the waiting call.

Note: The “B” (busy) signal line indicates availability of an 
announcement machine message to the trunk unit when configured for 
the continuous operation mode. This signal is made active (ground) by 
the announcement machine if the channel contains a recorded message 
and is in an online condition. The “B” line is not connected to a trunk unit 
when configured for start mode operation.

In a start mode (sometimes called the Code-a-Phone or start-stop mode), 
playback of a message does not begin until a start pulse is received by the 
announcement machine. Two subcategories of the start mode exist: pulse 
start and level start.

In the pulse start mode, a start pulse activates playback of a message that 
continues until completion. The announcement machine ignores all other start 
pulses that might occur until the message is complete. 

In the level start mode, the start signal is a “level” rather than a pulse. The 
leading edge of the start signal initiates message playback that continues until 
either the trailing edge of the start signal occurs or the end of the message is 
reached. A message that is terminated by the trailing edge of a level start 
signal is immediately reset and ready for playback again.