adiStartMFDetector

Enables the detection of MFs (multi-frequency tones).

Supported board types

Prototype

DWORD adiStartMFDetector ( CTAHD ctahd, unsigned mftype)

Argument

Description

ctahd

Context handle returned by ctaCreateContext or ctaAttachContext.

mftype

Type of MF tone to detect:

ADI_MF_US

ADI_MF_CCITT_FORWARD

ADI_MF_CCITT_BACKWARD

Return values

Return value

Description

SUCCESS

 

ADIERR_INVALID_CALL_STATE

Function not valid in the current call state.

CTAERR_FUNCTION_ACTIVE

Function already started.

CTAERR_FUNCTION_NOT_AVAIL

mf.dsp not loaded to the board.

CTAERR_INVALID_CTAHD

Context handle is invalid.

CTAERR_INVALID_STATE

Function not valid in the current port state.

CTAERR_SVR_COMM

Server communication error.

Events

Event

Description

ADIEVN_MF_DETECT_DONE

DTMF detector is no longer running. The event value field contains one of the following:

CTA_REASON_RELEASED

Call terminated.

CTA_REASON_STOPPED

Function stopped by adiStopMFDetector.

CTAERR_xxx or ADIERR_xxx

DTMF detector failed.

ADIEVN_MF_DIGIT_BEGIN

MF digit detected on.

ADIEVN_MF_DIGIT_END

MF digit detected off.

Details

The following DSP file must be loaded to the board before running adiStartMFDetector:

For these boards...

Load this DSP file...

AG

mf.m54

CG

mf.f54

See DSP file summary for DSP file descriptions. Refer to the board installation and developer's manual for a table of MIPS usage for all functions.

Use this function to enable detection of MFs (multi-frequency tones). Stop the function by calling adiStopMFDetector.

You must disable DTMF detection using adiStopDTMFDetector before initiating MF detection, as there are some overlapping frequency ranges in which both a DTMF and an MF event are reported. Likewise, when the application is finished with MF detection, re-enable DTMF detection (adiStartMFDetector) if DTMFs are desired.

ADIEVN_MF_DIGIT_BEGIN and ADIEVN_MF_DIGIT_END are generated for every MF tone detected. Each event contains an ASCII representation (character) of the MF digit in the event value field.

This table lists 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

The following table lists the mapping to the United States MF digits for MF dialing:

Digit

United States MF name

0 to 9

Specific digit address

B

MF ST3P

C

MF STP

D

MF KP

E

MF KP2, MF ST2P

F

MF ST

Note: The digit values are the same as those used by adiStartDTMF and adiStartDial when MF digits are dialed.

See also

adiStartDTMFDetector, adiStopDTMFDetector