2.4.2.3 Digit Monitoring

Digit monitoring monitors the call for digits. The SPI provides for digits to be signaled according to two methods (digit modes):

pulse - Digits are signaled as pulse/rotary sequences. Note that for detection, these pulses manifest themselves as nothing more than sequences of audible clicks. Valid pulse digits are '0' through '9'.
DTMF - Digits are signaled as DTMF (Dual Tone Multiple Frequency) tones. Valid DTMF digits are '0' through '9', 'A'. 'B', 'C', 'D', '*', and '#'. Both the beginning and the down edge of DTMF digits can be monitored. Digit monitoring can be enabled/disabled via TSPI_lineMonitorDigits. If enabled, all detected digits cause the TAPI DLL to be notified via the LINE_MONITORDIGITS callback. The callback provides the call handle on which the digit was detected as well as the digit value and the digit mode.

TSPI_lineMonitorDigits

Enables or disables digit detection notification on a specified call.

LINE_MONITORDIGITS

Notifies the application about a digit detection.

Note that the scope of digit monitoring is bound by the lifetime of the call. Digit monitoring on a call ends as soon the call disconnects or goes idle.