56 Voice API Programming Guide — June 2005
Call Progress Analysis
detects live voice as accurately as PAMD_FULL but is more accurate than PAMD_FULL
(although slightly slower) in detecting an answering machine. Use the setting
PAMD_ACCU when accuracy is more important than speed.
Default value (DM3 boards): PAMD_ACCU
The recommended setting for the call analysis parameter structure (DX_CAP)
ca_pamd_spdval field is PAMD_ACCU.
ca_pamd_failtime
maximum time to wait for positive answering machine detection or positive voice detection
after a cadence break. Default Value: 400 (in 10 msec units).
7.7 Default Call Progress Analysis Tone Definitions on DM3 Boards
Table6 provides the range of values for default tone definitions for DM3 boards. These default
tone definitions are used in call progress analysis. Amplitudes are given in dBm, frequencies in Hz,
and duration in 10 msec units. A dash in a table cell means not applicable.
Notes: 1. On DM3 boards, voice API functions are provided to manipulate the tone definitions in this table
(see Section7.8, “Modi fying Default Call Progress Analysis Tone Definitions on DM3 Boards”,
on page 57). However, not all the functionality provided by these tones is available through the
voice API. You may need to use the Global Call API to access the functionality, for example, in
the case of dial tone detection and disconnect tone detection.
2. An On Time maximum value of 0 indicates that this is a continuous tone. For example,
TID_DIAL_LCL has an On Time range of 10 to 0. This means that the tone is on for 100 msecs.
The minimum requirement for detecting a tone is that it must be continuous for at least 100
msecs (10 in 10 msec units) after it is detected.
3. A single tone proxy for a dual tone (twin tone) can help improve the accuracy of dual tone
detection in some cases. For more information, see Section 7.8.4, “Rules for Using a Single Tone
Proxy for a Dual Tone”, on page59.