46 Voice API Programming Guide — June 2005
Call Progress Analysis
Figure 3. PerfectCall Call Progress Analysis Components
7.4 Using Call Progress Analysis on DM3 Boards
The following topics provide information on how to use call progress analysis on DM3 boards:
•Call Progress Analysis Rules on DM3 Boards
•Overview of Steps to Initiate Call Progress Analysis
•Setting Up Call Progress Analysis Parameters in DX_CAP
•Executing a Dial Function
•Determining the Outcome of a Call
•Obtaining Additional Call Outcome Information

7.4.1 Call Progress Analysis Rules on DM3 Boards

The following rules apply to the use of call progress analysis on DM3 boards:
•It is recommended that all applications use the Global Call API for call progress analysis on
DM3 boards. For more information, see the Global Call API Programming Guide. However,
for backward compatibility, applications that use ISDN protocols can still enable call progress
analysis using dx_dial( ).
•If you choose to use dx_dial() in ISDN applications, do not mix the use of the Global Call
API and the Voice API within a phase of call progress analysis (pre-connect or post-connect).
•If you use channel associated signaling (CAS) or analog protocols, the following rules apply:
–Pre-connect is typically provided by the protocol via the Global Call API.
–The dx_dial( ) function cannot be used for pre-connect.
–If post-connect is disabled in the protocol, then dx_dial( ) is available for post-connect.
Incoming
Signal
Frequency
Detection
Cadence
Detection
Loop
Current
Detection
Intercept
(SIT)
No
Ringback
Busy No
Answer Connect
Fax Tone
No
Dialtone
Positive
Voice or
Answering
Machine
Detection