Diva SDK and SIT

Telco networks often generate Special Information Tones (SIT tones) in order to indicate that a number is out of service in some way. A number of these SIT messages exist and have different meanings, but they all consist of three tones played in sequence, where each tone has a higher pitch than the previous tone. 

The Dialogic Diva Media Board can detect these tones, and so it is possible to use this in an application to give additional information on call progress, and to take special action if an 'out of service' number or line is called. 

Using the Dialogic Diva Software Development Kit (Diva SDK), it is possible to use SIT tones in the following way: 

1. After the call is connected, make a call to DivaReportTones() to switch on the reporting of continuous tones to the application. 

2. In your callback routine or event handler you need to handle the event DivaEventToneDetected. 

When this event arrives, the two parameters contain: 
(a) your application handle and 
(b) the value of the continuous tone as defined by the type DivaContinuousTones. 

3. Then use an if or case to find the tone DivaSpecialInformationTone. If this message arrives at your application, then the Diva Media Board has detected one of the SIT tones on the line.