modem_connect_tones.h File Reference

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Defines
#define	MODEM_CONNECT_TONES_FAX_CED   MODEM_CONNECT_TONES_ANS
	FAX CED tone is the same as ANS tone.
Typedefs
typedef struct modem_connect_tones_tx_state_s	modem_connect_tones_tx_state_t
typedef struct modem_connect_tones_rx_state_s	modem_connect_tones_rx_state_t
Enumerations
enum	{   MODEM_CONNECT_TONES_NONE = 0, MODEM_CONNECT_TONES_FAX_CNG = 1, MODEM_CONNECT_TONES_ANS = 2, MODEM_CONNECT_TONES_ANS_PR = 3,   MODEM_CONNECT_TONES_ANSAM = 4, MODEM_CONNECT_TONES_ANSAM_PR = 5, MODEM_CONNECT_TONES_FAX_PREAMBLE = 6, MODEM_CONNECT_TONES_FAX_CED_OR_PREAMBLE = 7 }
Functions
modem_connect_tones_tx_state_t *	modem_connect_tones_tx_init (modem_connect_tones_tx_state_t *s, int tone_type)
	Initialise an instance of the modem connect tones generator.
int	modem_connect_tones_tx_release (modem_connect_tones_tx_state_t *s)
	Release an instance of the modem connect tones generator.
int	modem_connect_tones_tx_free (modem_connect_tones_tx_state_t *s)
	Free an instance of the modem connect tones generator.
	SPAN_DECLARE_NONSTD (int) modem_connect_tones_tx(modem_connect_tones_tx_state_t *s
	Generate a block of modem connect tones samples.
int	modem_connect_tones_rx_get (modem_connect_tones_rx_state_t *s)
	Test if a modem_connect tone has been detected.
modem_connect_tones_rx_state_t *	modem_connect_tones_rx_init (modem_connect_tones_rx_state_t *s, int tone_type, tone_report_func_t tone_callback, void *user_data)
	Initialise an instance of the modem connect tones detector.
int	modem_connect_tones_rx_release (modem_connect_tones_rx_state_t *s)
	Release an instance of the modem connect tones detector.
int	modem_connect_tones_rx_free (modem_connect_tones_rx_state_t *s)
	Free an instance of the modem connect tones detector.
const char *	modem_connect_tone_to_str (int tone)
Variables
int16_t	amp []
int16_t int	len

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Detailed Description

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Typedef Documentation

typedef struct modem_connect_tones_rx_state_s modem_connect_tones_rx_state_t

Modem connect tones receiver descriptor. This defines the state of a single working instance of the tone detector.

typedef struct modem_connect_tones_tx_state_s modem_connect_tones_tx_state_t

Modem connect tones generator descriptor. This defines the state of a single working instance of the tone generator.

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Enumeration Type Documentation

anonymous enum

Enumerator:

MODEM_CONNECT_TONES_NONE	This is reported when a tone stops.
MODEM_CONNECT_TONES_FAX_CNG	CNG tone is a pure 1100Hz tone, in 0.5s bursts, with 3s silences in between. The bursts repeat for as long as is required.
MODEM_CONNECT_TONES_ANS	ANS tone is a pure continuous 2100Hz+-15Hz tone for 3.3s+-0.7s.
MODEM_CONNECT_TONES_ANS_PR	ANS with phase reversals tone is a 2100Hz+-15Hz tone for 3.3s+-0.7s, with a 180 degree phase jump every 450ms+-25ms.
MODEM_CONNECT_TONES_ANSAM	The ANSam tone is a version of ANS with 20% of 15Hz+-0.1Hz AM modulation, as per V.8.
MODEM_CONNECT_TONES_ANSAM_PR	The ANSam with phase reversals tone is a version of ANS_PR with 20% of 15Hz+-0.1Hz AM modulation, as per V.8.
MODEM_CONNECT_TONES_FAX_PREAMBLE	FAX preamble in a string of V.21 HDLC flag octets.
MODEM_CONNECT_TONES_FAX_CED_OR_PREAMBLE	CED tone is the same as ANS tone. FAX preamble in a string of V.21 HDLC flag octets. This is only valid as a tone type to receive. It is never reported as a detected tone type. The report will either be for FAX preamble or CED/ANS tone.

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Function Documentation

int modem_connect_tones_rx_free

(

modem_connect_tones_rx_state_t *

s

)

Free an instance of the modem connect tones detector.

Parameters:

s	The context.

Returns:

0 for OK, else -1.

int modem_connect_tones_rx_get

(

modem_connect_tones_rx_state_t *

s

)

Test if a modem_connect tone has been detected.

Parameters:

s	The context.

Returns:

TRUE if tone is detected, else FALSE.

References MODEM_CONNECT_TONES_NONE.

modem_connect_tones_rx_state_t* modem_connect_tones_rx_init	(	modem_connect_tones_rx_state_t *	s,
		int	tone_type,
		tone_report_func_t	tone_callback,
		void *	user_data
	)

Initialise an instance of the modem connect tones detector.

Parameters:

s	The context.
tone_type	The type of connect tone being tested for.
tone_callback	An optional callback routine, used to report tones
user_data	An opaque pointer passed to the callback routine,

Returns:

A pointer to the context.

References fsk_rx_init(), fsk_rx_signal_cutoff(), MODEM_CONNECT_TONES_ANS, MODEM_CONNECT_TONES_ANS_PR, MODEM_CONNECT_TONES_ANSAM, MODEM_CONNECT_TONES_ANSAM_PR, MODEM_CONNECT_TONES_FAX_CED_OR_PREAMBLE, MODEM_CONNECT_TONES_FAX_PREAMBLE, and MODEM_CONNECT_TONES_NONE.

int modem_connect_tones_rx_release

(

modem_connect_tones_rx_state_t *

s

)

Release an instance of the modem connect tones detector.

Parameters:

s	The context.

Returns:

0 for OK, else -1.

int modem_connect_tones_tx_free

(

modem_connect_tones_tx_state_t *

s

)

Free an instance of the modem connect tones generator.

Parameters:

s	The context.

Returns:

0 for OK, else -1.

modem_connect_tones_tx_state_t* modem_connect_tones_tx_init	(	modem_connect_tones_tx_state_t *	s,
		int	tone_type
	)

Initialise an instance of the modem connect tones generator.

Parameters:

s	The context.

References dds_phase_rate(), dds_scaling_dbm0(), MODEM_CONNECT_TONES_ANS, MODEM_CONNECT_TONES_ANS_PR, MODEM_CONNECT_TONES_ANSAM, MODEM_CONNECT_TONES_ANSAM_PR, and MODEM_CONNECT_TONES_FAX_CNG.

int modem_connect_tones_tx_release

(

modem_connect_tones_tx_state_t *

s

)

Release an instance of the modem connect tones generator.

Parameters:

s	The context.

Returns:

0 for OK, else -1.

SPAN_DECLARE_NONSTD

(

int

)

Generate a block of modem connect tones samples.

Get the next bit of data from a T.38 rate adapting non-ECM buffer context.

Get a bit of received non-ECM image data.

Get the next bit of a transmitted serial bit stream.

Process a block of samples through an instance of the modem connect tones detector.

Parameters:

s	The context.
amp	An array of signal samples.
len	The number of samples to generate.

Returns:

The number of samples generated.

Parameters:

s	The context.
amp	An array of signal samples.
len	The number of samples in the array.

Returns:

The number of unprocessed samples.