Insys ISDN Terminal Adapter 4.0 11-02-01-02-00.015 Manuale Utente

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Operating Manual INSYS ISDN TA 4.0 

 

 

Version 2.02 – 01.04 

The S0 bus consists of a transmitting and a receiver circuit. The data stream of 
144kbit/s in the transmitting and receiver circuit divides into 2 utilizable channels (B 
channel, in each case 64 kbit/s) and 1 signaling channel (D channel, 16kbit/s). 

The primary rate interface is intended for the supply of larger ISDN ISPBXs (integrated 
services private branch exchanges), which have a large requirement of transmission 
channels. 

 

The primary rate interface, abbreviated PMxA or PRI, has 30 utilizable channels as PBX 
connection. 
The connection is made by two conventional two-wire lines and a primary multiplex 
network termination (PMx NT). A ISPBX is connected to this NT using the so-called S2M 
port. The data transmission rate at the primary multiplex port (30 utilizable channels + 
1 data channel) is 2 Mbit/s. 
Each utilizable channel (B channel) uses a transmission speed of 64 kbit/s. Additionally 
to the utilizable channels a so-called data channel (D channel, see D channel) exists, 
which is used for the signaling information. Moreover additional synchronization in-
formation is transmitted.