AVT MAGIC ISDN, Описание аппаратуры

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PA G E 3 6
3.4.4 Audio transmission via ISDN
FIGURE 3.5 A UDIO TRANSMISSION VIA
ISDN
WITH
2 B
CHANNELS
In this application, the uni-directional transmission of a high-quality audio si-
gnal via an ISDN connection (128 kbit/s) is shown. To set up a bi-directional
Audio connection, the MAGIC ISDN System (or e.g. a MusicTaxi) equipment
must have the same settings at both ends of the transmission path. MAGIC
systems in ISDN operation can be used to transmit Audio data at up to 384-
kbit/s. For all six B-channels, a transit time delay compensation is carried out.
Then a "Capability Exchange" takes place in which the terminals exchange in-
formation on their encoding and decoding capabilities. At the end of this pro-
cedure, the audio signals are transmitted in the best possible mode (unless
this is limited by the use of further data services). If MusicTAXI signalling has
been selected, a 2B connection is set up. Several features such as an addi-
tional "Low Speed Data" channel or the complete remote control of systems
are therefore not possible in this mode.
RS232C
Line X.21 HSD LSD
Additional Data
Slot 2 Slot 3 RS232-Aux RS485
Extension Bus
TTL User I/O
Handset
ISDN 1 ISDN 2 ISDN 3
Clock Out
CMD In CMD Out Left In Left Out Right Out Right In Aux In Aux Out Dig In Dig Out
Dig In Dig Out
Slot 2 Slot 3
POWER 115/230V
0 I
LEFT OUTPUT RIGHT OUTPUT CMD INPUT
EXTENSION BUS
USER I/O X.21/SLAVE 4 X.21/SLAVE 2 X.21/MAIN
X.21/SLAVE 1 X.21/SLAVE 3 X.21/SLAVE 5 LSD RS232C
ADD.DATA
Loudspeaker, modulator
Transmission of an Audio programme
MAGIC ISDN
left
right
#inclu
TA MULTI
ISDN channel B1 ISDN channel B2
J.52 J.52
Audio
Audio
LSD
ISDN 2B channel assignment (optional data channel and command channel):
CMD
MAGIC System control
+5&0