t31.c File Reference

#include <inttypes.h>
#include <stdlib.h>
#include <stdio.h>
#include <fcntl.h>
#include <time.h>
#include <memory.h>
#include <string.h>
#include <ctype.h>
#include "floating_fudge.h"
#include <assert.h>
#include <tiffio.h>
#include "spandsp/telephony.h"
#include "spandsp/logging.h"
#include "spandsp/bit_operations.h"
#include "spandsp/dc_restore.h"
#include "spandsp/queue.h"
#include "spandsp/power_meter.h"
#include "spandsp/complex.h"
#include "spandsp/tone_detect.h"
#include "spandsp/tone_generate.h"
#include "spandsp/async.h"
#include "spandsp/hdlc.h"
#include "spandsp/silence_gen.h"
#include "spandsp/fsk.h"
#include "spandsp/v29rx.h"
#include "spandsp/v29tx.h"
#include "spandsp/v27ter_rx.h"
#include "spandsp/v27ter_tx.h"
#include "spandsp/v17rx.h"
#include "spandsp/v17tx.h"
#include "spandsp/super_tone_rx.h"
#include "spandsp/modem_connect_tones.h"
#include "spandsp/t4.h"
#include "spandsp/t30.h"
#include "spandsp/t30_logging.h"
#include "spandsp/t38_core.h"
#include "spandsp/at_interpreter.h"
#include "spandsp/fax_modems.h"
#include "spandsp/t31.h"


Defines
#define	MS_PER_TX_CHUNK 30
#define	INDICATOR_TX_COUNT 3
#define	DATA_TX_COUNT 1
#define	DATA_END_TX_COUNT 3
#define	DEFAULT_DTE_TIMEOUT 5
#define	MAX_OCTETS_PER_UNPACED_CHUNK 300
#define	MID_RX_TIMEOUT 15000
#define	HDLC_FRAMING_OK_THRESHOLD 5
#define	ETX 0x03
#define	DLE 0x10
#define	SUB 0x1A
Typedefs
typedef const char (	at_cmd_service_t )(t31_state_t s, const char cmd)
Enumerations
enum	{ T31_NONE = -1, T31_FLUSH = 0, T31_SILENCE_TX, T31_SILENCE_RX, T31_CED_TONE, T31_CNG_TONE, T31_NOCNG_TONE, T31_V21_TX, T31_V17_TX, T31_V27TER_TX, T31_V29_TX, T31_V21_RX, T31_V17_RX, T31_V27TER_RX, T31_V29_RX }
enum	{ T38_TIMED_STEP_NONE = 0, T38_TIMED_STEP_NON_ECM_MODEM, T38_TIMED_STEP_NON_ECM_MODEM_2, T38_TIMED_STEP_NON_ECM_MODEM_3, T38_TIMED_STEP_NON_ECM_MODEM_4, T38_TIMED_STEP_NON_ECM_MODEM_5, T38_TIMED_STEP_HDLC_MODEM, T38_TIMED_STEP_HDLC_MODEM_2, T38_TIMED_STEP_HDLC_MODEM_3, T38_TIMED_STEP_HDLC_MODEM_4, T38_TIMED_STEP_CED, T38_TIMED_STEP_CED_2, T38_TIMED_STEP_CNG, T38_TIMED_STEP_CNG_2, T38_TIMED_STEP_PAUSE }
Functions
int	t31_t38_send_timeout (t31_state_t *s, int samples)
void	t31_call_event (t31_state_t *s, int event)
int	t31_at_rx (t31_state_t s, const char t, int len)
int	t31_rx (t31_state_t *s, int16_t amp[], int len)
	Process a block of received T.31 modem audio samples.
int	t31_tx (t31_state_t *s, int16_t amp[], int max_len)
	Generate a block of T.31 modem audio samples.
void	t31_set_transmit_on_idle (t31_state_t *s, int transmit_on_idle)
	Select whether silent audio will be sent when transmit is idle.
void	t31_set_tep_mode (t31_state_t *s, int use_tep)
	Select whether TEP mode will be used.
void	t31_set_t38_config (t31_state_t *s, int without_pacing)
	Select whether T.38 data will be paced.
t31_state_t *	t31_init (t31_state_t s, at_tx_handler_t at_tx_handler, void at_tx_user_data, t31_modem_control_handler_t modem_control_handler, void modem_control_user_data, t38_tx_packet_handler_t tx_t38_packet_handler, void *tx_t38_packet_user_data)
	Initialise a T.31 context.
int	t31_release (t31_state_t *s)
	Release a T.31 context.

Detailed Description

Function Documentation

t31_state_t* t31_init	(	t31_state_t *	s,
		at_tx_handler_t *	at_tx_handler,
		void *	at_tx_user_data,
		t31_modem_control_handler_t *	modem_control_handler,
		void *	modem_control_user_data,
		t38_tx_packet_handler_t *	tx_t38_packet_handler,
		void *	tx_t38_packet_user_data
	)

Initialise a T.31 context.

Initialise a T.31 context. This must be called before the first use of the context, to initialise its contents.

Parameters:

	s	The T.31 context.
	at_tx_handler	A callback routine to handle AT interpreter channel output.
	at_tx_user_data	An opaque pointer passed in called to at_tx_handler.
	modem_control_handler	A callback routine to handle control of the modem (off-hook, etc).
	modem_control_user_data	An opaque pointer passed in called to modem_control_handler.
	tx_t38_packet_handler	???
	tx_t38_packet_user_data	???

Returns:: A pointer to the T.31 context.

References at_init(), t31_state_s::at_state, t31_state_s::audio, t31_state_s::call_samples, at_state_s::do_hangup, at_state_s::dte_inactivity_timeout, t31_audio_front_end_state_t::last_sample, at_state_s::line_ptr, t31_state_s::logging, t31_state_s::modem, t31_state_s::modem_control_handler, t31_state_s::modem_control_user_data, t31_audio_front_end_state_t::modems, power_meter_init(), power_meter_level_dbm0(), queue_init(), QUEUE_READ_ATOMIC, QUEUE_WRITE_ATOMIC, t31_audio_front_end_state_t::rx_power, t31_state_s::rx_queue, at_state_s::rx_signal_present, at_state_s::rx_trained, t31_state_s::silence_awaited, t31_audio_front_end_state_t::silence_heard, t31_audio_front_end_state_t::silence_threshold_power, t31_set_t38_config(), t31_t38_front_end_state_t::t38, t31_state_s::t38_fe, t31_state_s::t38_mode, and at_state_s::transmit.

int t31_release ( t31_state_t * s )

Release a T.31 context.

Parameters:

s

The T.31 context.

Returns:: 0 for OK

References t31_state_s::at_state.

int t31_rx	(	t31_state_t *	s,
		int16_t	amp[],
		int	len
	)

Process a block of received T.31 modem audio samples.

Parameters:

	s	The T.31 modem context.
	amp	The audio sample buffer.
	len	The number of samples in the buffer.

Returns:: The number of samples unprocessed.

References t31_state_s::at_state, t31_state_s::audio, t31_state_s::call_samples, t31_state_s::dte_data_timeout, t31_audio_front_end_state_t::last_sample, t31_state_s::modem, t31_audio_front_end_state_t::modems, power_meter_update(), fax_modems_state_t::rx_handler, t31_audio_front_end_state_t::rx_power, fax_modems_state_t::rx_user_data, t31_audio_front_end_state_t::silence_heard, t31_audio_front_end_state_t::silence_threshold_power, and at_state_s::transmit.

void t31_set_t38_config	(	t31_state_t *	s,
		int	without_pacing
	)

Select whether T.38 data will be paced.

Select whether T.38 data will be paced as it is transmitted.

Parameters:

	s	The T.31 modem context.
	without_pacing	TRUE if data is to be sent as fast as possible. FALSE if it is to be paced.

References t38_core_state_s::data_end_tx_count, t38_core_state_s::indicator_tx_count, t31_t38_front_end_state_t::ms_per_tx_chunk, t31_t38_front_end_state_t::t38, and t31_state_s::t38_fe.

Referenced by t31_init().

void t31_set_tep_mode	(	t31_state_t *	s,
		int	use_tep
	)

Select whether TEP mode will be used.

Select whether TEP mode will be used (or time allowed for it (when transmitting).

Parameters:

	s	The T.31 modem context.
	use_tep	TRUE if TEP is to be ised.

References t31_state_s::audio, t31_audio_front_end_state_t::modems, and fax_modems_state_t::use_tep.

void t31_set_transmit_on_idle	(	t31_state_t *	s,
		int	transmit_on_idle
	)

Select whether silent audio will be sent when transmit is idle.

Parameters:

	s	The T.31 modem context.
	transmit_on_idle	TRUE if silent audio should be output when the transmitter is idle. FALSE to transmit zero length audio when the transmitter is idle. The default behaviour is FALSE.

References t31_state_s::audio, t31_audio_front_end_state_t::modems, and fax_modems_state_t::transmit_on_idle.

int t31_tx	(	t31_state_t *	s,
		int16_t	amp[],
		int	max_len
	)

Generate a block of T.31 modem audio samples.

Parameters:

	s	The T.31 modem context.
	amp	The audio sample buffer.
	max_len	The number of samples to be generated.

Returns:: The number of samples actually generated.

References AT_MODEM_CONTROL_HANGUP, t31_state_s::at_state, t31_state_s::audio, at_state_s::do_hangup, t31_state_s::modem, t31_audio_front_end_state_t::modems, at_state_s::transmit, fax_modems_state_t::transmit_on_idle, fax_modems_state_t::tx_handler, and fax_modems_state_t::tx_user_data.

t31.c File Reference

Defines

Typedefs

Enumerations

Functions

Detailed Description

Function Documentation