# adiStartDTMF

Starts generating a string of DTMF
s or MF
s.

#### Supported board types

- AG

- CG

#### Prototype

DWORD adiStartDTMF ( CTAHD ctahd, char *digits, ADI_DTMF_PARMS *parms)

Argument | Description
ctahd | Context handle returned by ctaCreateContext or ctaAttachContext.
digits | Pointer to a string of DTMF digits including 0 though 9, A through F, * (asterisk), # (number sign), and , (comma) or . (period) for pauses. All other characters are ignored.
parms | Pointer to DTMF parameters according to the following structure (NULL value uses the default values): typedef struct { DWORD size; /* size of this structure */ INT32 ampl1; /* level of first tone (dBm) */ INT32 ampl2; /* level of second tone (dBm) */ DWORD ontime; /* on duration of DTMF tone (ms) */ DWORD offtime; /* off duration of DTMF tone (ms) */ DWORD shortpause;/* duration of ',' (ms) */ DWORD longpause /* duration of '.' (ms) */ } ADI_DTMF_PARMS; In some instances, the dtmfofftime can increase by 20 ms. Refer to ADI_DTMF_PARMS for field descriptions.

#### Return values

Return value | Description
SUCCESS |
CTAERR_INVALID_CTAHD | Context handle is invalid.
CTAERR_OUTPUT_ACTIVE | Open port failed because the stream and slot are already opened on another port.
CTAERR_SVR_COMM | Server communication error.

#### Events

Event | Description
ADIEVN_TONES_DONE | Value field can contain CTA_REASON_FINISHED or CTA_REASON_STOPPED.

#### Details

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

For these boards... | Load this DSP file...
AG | tone.m54
CG | tone.f54

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

Use this function to start generating a sequence of DTMF tones or MF tones. Use adiStopTones to terminate DTMF or MF generation.

Note: While adiStartDTMF is active, the DTMF detector is disabled.

digits can contain the following embedded escape characters that control the dialing sequence:

Character | Description
--- | ---
. | (period) Insert long pause in dialing.
, | (comma) Insert short pause in dialing.
T | Switch to DTMF dialing (default).
M | Switch to MF dialing.

To generate MF tones, precede the string with an M.

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

#### See also

adiStartTones