spandsp  0.0.6
v27ter_rx.h File Reference

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Typedefs

typedef struct v27ter_rx_state_s v27ter_rx_state_t
 

Functions

v27ter_rx_state_tv27ter_rx_init (v27ter_rx_state_t *s, int bit_rate, put_bit_func_t put_bit, void *user_data)
 Initialise a V.27ter modem receive context. More...
 
int v27ter_rx_restart (v27ter_rx_state_t *s, int bit_rate, int old_train)
 Reinitialise an existing V.27ter modem receive context. More...
 
int v27ter_rx_release (v27ter_rx_state_t *s)
 Release a V.27ter modem receive context. More...
 
int v27ter_rx_free (v27ter_rx_state_t *s)
 Free a V.27ter modem receive context. More...
 
logging_state_tv27ter_rx_get_logging_state (v27ter_rx_state_t *s)
 Get the logging context associated with a V.27ter modem receive context. More...
 
void v27ter_rx_set_put_bit (v27ter_rx_state_t *s, put_bit_func_t put_bit, void *user_data)
 Change the put_bit function associated with a V.27ter modem receive context. More...
 
void v27ter_rx_set_modem_status_handler (v27ter_rx_state_t *s, modem_status_func_t handler, void *user_data)
 Change the modem status report function associated with a V.27ter modem receive context. More...
 
 SPAN_DECLARE_NONSTD (int) v27ter_rx(v27ter_rx_state_t *s
 Process a block of received V.27ter modem audio samples. More...
 
int v27ter_rx_equalizer_state (v27ter_rx_state_t *s, complexf_t **coeffs)
 Get a snapshot of the current equalizer coefficients. More...
 
float v27ter_rx_carrier_frequency (v27ter_rx_state_t *s)
 
float v27ter_rx_symbol_timing_correction (v27ter_rx_state_t *s)
 
float v27ter_rx_signal_power (v27ter_rx_state_t *s)
 
void v27ter_rx_signal_cutoff (v27ter_rx_state_t *s, float cutoff)
 
void v27ter_rx_set_qam_report_handler (v27ter_rx_state_t *s, qam_report_handler_t handler, void *user_data)
 

Variables

const int16_t amp []
 
const int16_t int len
 

Typedef Documentation

◆ v27ter_rx_state_t

V.27ter modem receive side descriptor. This defines the working state for a single instance of a V.27ter modem receiver.

Function Documentation

◆ SPAN_DECLARE_NONSTD()

SPAN_DECLARE_NONSTD ( int  )

Process a block of received V.27ter modem audio 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.

Fake processing of a missing block of received V.27ter modem audio samples.

Process a block of received V.27ter modem audio samples.

Parameters
sThe modem context.
ampThe audio sample buffer.
lenThe number of samples in the buffer.
Returns
The number of samples unprocessed.

Fake processing of a missing block of received V.27ter modem audio samples. (e.g due to packet loss).

Parameters
sThe modem context.
lenThe number of samples to fake.
Returns
The number of samples unprocessed.

◆ v27ter_rx_carrier_frequency()

float v27ter_rx_carrier_frequency ( v27ter_rx_state_t s)

Get the current received carrier frequency.

Parameters
sThe modem context.
Returns
The frequency, in Hertz.

References v27ter_rx_state_s::carrier_phase_rate, and dds_frequencyf().

◆ v27ter_rx_equalizer_state()

int v27ter_rx_equalizer_state ( v27ter_rx_state_t s,
complexf_t **  coeffs 
)

Get a snapshot of the current equalizer coefficients.

Get a snapshot of the current equalizer coefficients.

Parameters
coeffsThe vector of complex coefficients.
Returns
The number of coefficients in the vector.

References v27ter_rx_state_s::eq_coeff.

◆ v27ter_rx_free()

int v27ter_rx_free ( v27ter_rx_state_t s)

Free a V.27ter modem receive context.

Free a V.27ter modem receive context.

Parameters
sThe modem context.
Returns
0 for OK

◆ v27ter_rx_get_logging_state()

logging_state_t* v27ter_rx_get_logging_state ( v27ter_rx_state_t s)

Get the logging context associated with a V.27ter modem receive context.

Get the logging context associated with a V.27ter modem receive context.

Parameters
sThe modem context.
Returns
A pointer to the logging context

References v27ter_rx_state_s::logging.

◆ v27ter_rx_init()

v27ter_rx_state_t* v27ter_rx_init ( v27ter_rx_state_t s,
int  bit_rate,
put_bit_func_t  put_bit,
void *  user_data 
)

Initialise a V.27ter modem receive context.

Initialise a V.27ter modem receive context.

Parameters
sThe modem context.
bit_rateThe bit rate of the modem. Valid values are 2400 and 4800.
put_bitThe callback routine used to put the received data.
user_dataAn opaque pointer passed to the put_bit routine.
Returns
A pointer to the modem context, or NULL if there was a problem.

◆ v27ter_rx_release()

int v27ter_rx_release ( v27ter_rx_state_t s)

Release a V.27ter modem receive context.

Release a V.27ter modem receive context.

Parameters
sThe modem context.
Returns
0 for OK

◆ v27ter_rx_restart()

int v27ter_rx_restart ( v27ter_rx_state_t s,
int  bit_rate,
int  old_train 
)

Reinitialise an existing V.27ter modem receive context.

Reinitialise an existing V.27ter modem receive context.

Parameters
sThe modem context.
bit_rateThe bit rate of the modem. Valid values are 2400 and 4800.
old_trainTRUE if a previous trained values are to be reused.
Returns
0 for OK, -1 for bad parameter

◆ v27ter_rx_set_modem_status_handler()

void v27ter_rx_set_modem_status_handler ( v27ter_rx_state_t s,
modem_status_func_t  handler,
void *  user_data 
)

Change the modem status report function associated with a V.27ter modem receive context.

Change the modem status report function associated with a V.27ter modem receive context.

Parameters
sThe modem context.
handlerThe callback routine used to report modem status changes.
user_dataAn opaque pointer.

References v27ter_rx_state_s::status_handler, and v27ter_rx_state_s::status_user_data.

◆ v27ter_rx_set_put_bit()

void v27ter_rx_set_put_bit ( v27ter_rx_state_t s,
put_bit_func_t  put_bit,
void *  user_data 
)

Change the put_bit function associated with a V.27ter modem receive context.

Change the put_bit function associated with a V.27ter modem receive context.

Parameters
sThe modem context.
put_bitThe callback routine used to handle received bits.
user_dataAn opaque pointer.

◆ v27ter_rx_set_qam_report_handler()

void v27ter_rx_set_qam_report_handler ( v27ter_rx_state_t s,
qam_report_handler_t  handler,
void *  user_data 
)

Set a handler routine to process QAM status reports

Parameters
sThe modem context.
handlerThe handler routine.
user_dataAn opaque pointer passed to the handler routine.

◆ v27ter_rx_signal_cutoff()

void v27ter_rx_signal_cutoff ( v27ter_rx_state_t s,
float  cutoff 
)

Set the power level at which the carrier detection will cut in

Parameters
sThe modem context.
cutoffThe signal cutoff power, in dBm0.

References v27ter_rx_state_s::carrier_off_power, v27ter_rx_state_s::carrier_on_power, and power_meter_level_dbm0().

◆ v27ter_rx_signal_power()

float v27ter_rx_signal_power ( v27ter_rx_state_t s)

Get a current received signal power.

Parameters
sThe modem context.
Returns
The signal power, in dBm0.

References v27ter_rx_state_s::power, and power_meter_current_dbm0().

◆ v27ter_rx_symbol_timing_correction()

float v27ter_rx_symbol_timing_correction ( v27ter_rx_state_t s)

Get the current symbol timing correction since startup.

Parameters
sThe modem context.
Returns
The correction.

References v27ter_rx_state_s::bit_rate, and v27ter_rx_state_s::total_baud_timing_correction.