ISDN Software Reference for Linux and Windows
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• cc_SndNonCallMsg( ) - Sends a non-Call State related message to the PBX.
This function does not require a call reference value.
• cc_SetInfoElem( ) - Sets an information element (IE) allowing the
application to include application-specific ISDN information elements in the
next outgoing message.
The following functions are used to retrieve Facility Messages:
• cc_GetCallInfo( ) - Retrieves the information elements associated with the
CRN.
• cc_GetNonCallMsg( ) - Retrieves a non-Call State related ISDN messages to
the PBX.
The cc_SndMsg( ) and cc_SndNonCallMsg( ) functions are used to send Facility
Messages or Notify Messages to the PBX. The Facility Message (as defined in
ETS 300-196-1) is composed of the following elements:
• Protocol discriminator
• Call reference
• Message type
• Facility Information Element
The Supplemental Service to be invoked and its associated parameters are
specified in the Information Element. This information is PBX-specific and
should be provided by the PBX manufacturer. Facility Messages are sent using
the cc_SndMsg( ) or cc_SndNonCallMsg( ) function with msg_type =
SndMsg_Facility. These functions
1. format the Facility Message, inserting the protocol discriminator, call
reference number (only for cc_SndMsg( )) and message type elements
2. add the Information Element data (stored in an application buffer)
3. send all the information to the PBX
The PBX, in turn, interprets and acts on the information, and sends a reply to the
BRI board.