The MonitorTone method is used to start and stop detection of an inband tone on the call. Duration defines the duration, in milliseconds, during which the tone should be present before a detection is made. Frequency1, Frequency2 and Frequency3 are the frequency, in hertz, of a component of the tone. If fewer than three frequencies are needed in the tone, a value of 0 should be used for the unused frequencies. A tone with all three frequencies set to zero is interpreted as silence and can be used for silence detection. Each time the specified tone is detected, a ThbTapiLine.OnTone event is triggered. The value of AppSpecific is given back to the application within this event.

Declaration

procedure MonitorTone(Frequency1, Frequency2, Frequency3, Duration, AppSpecific: DWORD);

Remarks

Please refer to the section "lineMonitorTones" in TAPI's documentation for a more detailed information.

Errors

Using this function may cause an EhbTapiError exception. Possible errors are:

LINEERR_INVALCALLHANDLE, LINEERR_INVALCALLSTATE, LINEERR_INVALPOINTER, LINEERR_INVALTONE, LINEERR_NOMEM, LINEERR_OPERATIONFAILED, LINEERR_OPERATIONUNAVAIL, LINEERR_RESOURCEUNAVAIL, LINEERR_UNINITIALIZED.

See Also

ThbTapiLine.OnTone