(Page 51 of 80 in this chapter)
adiStartMFDetector
Description
- Enables the detection of MFs (Multi Frequency tones).
Prototype
- DWORD adiStartMFDetector( CTAHD ctahd,
unsigned mftype )
- ctahd Context handle returned by adiOpenPort.
- mftype Type of MF tone to detect:
- ADI_MF_US
ADI_MF_CCITT_FORWARD
ADI_MF_CCITT_BACKWARD
Return Values
Events
DSP File Requirement
- This function requires that mf.dsp has been loaded by agmon.
Details
- This function enables detection of MFs (Multi Frequency tones). The function can be stopped by calling adiStopMFDetector.
- Note that you need to disable DTMF detection (adiStopDTMFDetector) before initiating MF detection, as there are some overlapping frequency ranges in which both a DTMF and an MF event will be reported. Likewise, when the application is finished with MF detection, make sure to re-enable DTMF detection (adiStartDTMFDetector) if DTMFs are desired.
- ADIEVN_MFDIGIT_BEGIN and ADIEVN_MFDIGIT_END events are generated for every MF tone detected. Each event contains an ASCII representation (character) of the MF digit, in the event value field (see the MF frequency table below).
- The following table describes the MF frequencies for each mftype, along with the digit value returned in the event's value field:
-
|
Digit
|
US MF
|
ITU Forward
|
ITU Backward
|
|---|
|
'1'
|
700,900
|
1380,1500
|
1140,1020
|
|
'2'
|
700,1100
|
1380,1620
|
1140,900
|
|
'3'
|
900,1100
|
1500,1620
|
1020,900
|
|
'4'
|
700,1300
|
1380,1740
|
1140,780
|
|
'5'
|
900,1300
|
1500,1740
|
1020,780
|
|
'6'
|
1100,1300
|
1620,1740
|
900,780
|
|
'7'
|
700,1500
|
1380,1860
|
1140,660
|
|
'8'
|
900,1500
|
1500,1860
|
1020,660
|
|
'9'
|
1100,1500
|
1620,1860
|
900,660
|
|
'0'
|
1300,1500
|
1740,1860
|
780,660
|
|
'B'
|
700,1700
|
1380,1980
|
1140,540
|
|
'C'
|
900,1700
|
1500,1980
|
1020,540
|
|
'D'
|
1100,1700
|
1620,1980
|
900,540
|
|
'E'
|
1300,1700
|
1740,1980
|
780,540
|
|
'F'
|
1500,1700
|
1860,1980
|
660,540
|
- Please note the mapping to the U.S. MF names:
-
- Note that the digit values are the same as those used by adiPlaceCall, adiStartDTMF, and adiStartDial, when MF digits are being dialed.
See Also
- adiStopMFDetector, adiStopDTMFDetector, adiStartDTMFDetector
(Page 51 of 80 in this chapter)
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