beautypg.com

Dialogic 6.2 User Manual

Page 266

background image

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

Using the BSMI R2 Signaling Capability

on

page 336

.

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