Dialogic 6.2 Manuale Utente

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General Information
November 2009
266
The protocols describe the value and meaning of the signaling bits 
and the timing between changes in their value.
Brooktrout modules support the following LEC protocols:
„
E&M Wink Start
„
E&M Immediate Start
„
E&M Delay Dial
„
FXO Loop Start
„
FXS Loop Start
„
FXO Ground Start
„
FXS Ground Start
All signaling modes support pulsed (10 pulses per second), DTMF 
and MF dialing. However, detection of digits must be handled by the 
host.
ITU's R2 protocol, normally used in E1 lines is also supported, and it 
is described in 
Wink Start, Immediate Start and Delay Dial protocols are typically 
used to connect equivalent devices (for example, Central Offices). 
The same protocol must be loaded on both channel involved in a call. 
Loop Start and Ground Start protocols connect different types of 
devices (a Central Office or PBX to a Station). In this case the side 
acting as Central Office must load the FXO (foreign exchange office) 
version of the protocol, while the Station side must load the FXS 
(foreign exchange station) version.
The messages and data structures used for the host application and 
the module to communicate form the BSMI interface, described in 
Volume 5 of the Bfv API Reference Manual. The same Bfv API is 
used also for ISDN and R2 — the same messages are used to 
control/notify similar events across all protocols.  
Structure IISDN_BCHANNEL_ID contains fields common to all 
CAS protocols plus data structures containing LEC- and R2-specific 
configuration (structures IISDN_ROBBED_BIT_DATA and IISDN_
E1_CAS_R2_DATA respectively). Some of the message fields have 
names that reflect their ISDN roots, but their definition is extended 
for use with all CAS protocols (LEC protocols as well as R2). The 
most important ones are lapdid, which in CAS protocols identifies 
the trunk number in the module (0-based) and call_ref, a 16-bit 
value in which the most-significant byte must always contain the 
trunk number (same value as lapdid) and the least significant byte