Telex Azedit Software Manual page 148

DBX Links
Use DBX Links to view information about the links between DBX (Dual Bus Expansion) cards in a multi-frame ADAM
intercom system that uses this type of card.
This item is only selectable in ONLINE mode when AZedit is connected to a DBX system.
Any of the following indications can be given:
<dash>: this link is not being used for audio
###-###: this link is being used for the timeslots indicated
Example 1
The following information would be displayed for a 2-frame system without redundant DBX cards. There is one DBX
card per frame (in slot 9). Both DBX cards are "active" in their frame, and ALL links are up.
DBX Status Link A Link B
1:009 OK Active OK ALL OK ALL
2:009 OK Active OK ALL OK ALL
Link A is not being used for audio in either direction. Link B, in frame 1, is being used to drive timeslots 129-252
from frame 2, and Link B in frame 2, is being used to drive timeslots 1-124 from frame 1.
Note, in systems where there is only 1 DBX card per frame (2 frame, and 3 frames systems without redundant
controllers), and if test audio is enabled, then only 124 timeslots can be forwarded between frames. A DBX link can
forward 128 timeslots, but test audio requires 4 timeslots per link. In the 256x256 (2 frame), and 384x384 (3 frame)
systems which have only 1 DBX card per frame, all timeslots per link are needed for audio, but if test audio is
enabled, the last 4 timeslots in each frame are not available.
This means that the last four ports in each frame can listen to, but not talk to ports in other frames. Similarly, ports in
other frames can talk to, but not listen to the last four ports in each frame. Within any frame, any port can talk or listen
to any other port in that frame, the timeslots are only lost going between frames.
Test Audio is artificially generated audio by the DBX that it can produce, publish, forward, receive, and test. It is used
by the DBX to ensure that the links are passing valid audio between frames. If the DBX detects that the link is up, but
that the audio is corrupt, the DBX tears down the link and builds it up again.
Example 2
DBX Status Link A Link B Audio A Audio B
1:009 OK Active OK 1
2:009 OK Active OK 1
In this example, the link connecting Port B of 1:9 to Port B of 2:9 has been broken. The audio automatically switched
over to the A links, and the "hop" count for the A links shows 1 instead of ALL.
Note, even though this intercom is called a 2 frame non-redundant system, it actually has redundant audio because
both links go between frame 1 and 2. The intercom does not have redundant control because there is only one DBX
card per frame, and if any card fails, connectivity is lost.
Note, it is possible for the audio from frame 1 to frame 2 to be carried on one link while audio in the other direction is
carried on another link.
148
Audio A Audio B
- 129-252
- 001-124
- - 129-252 -
- - 001-124 -
D
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