GNU Radio 3.4.2 C++ API
usrp_source_base Class Reference

abstract interface to Universal Software Radio Peripheral Rx path (Rev 1) More...

#include <usrp_source_base.h>

Inheritance diagram for usrp_source_base:

List of all members.

Public Member Functions

 ~usrp_source_base ()
int work (int noutput_items, gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
 just like gr_block::general_work, only this arranges to call consume_each for you
bool set_decim_rate (unsigned int rate)
 Set decimator rate. rate must be EVEN and in [8, 256].
bool set_nchannels (int nchan)
bool set_mux (int mux)
int determine_rx_mux_value (usrp_subdev_spec ss)
int determine_rx_mux_value (usrp_subdev_spec ss_a, usrp_subdev_spec ss_b)
bool set_rx_freq (int channel, double freq)
 set the center frequency of the digital down converter.
bool set_fpga_mode (int mode)
 set fpga special modes
bool set_ddc_phase (int channel, int phase)
 Set the digital down converter phase register.
long adc_rate () const
long adc_freq () const
unsigned int decim_rate () const
int nchannels () const
int mux () const
double rx_freq (int channel) const
int noverruns () const
bool has_rx_halfband ()
bool has_tx_halfband ()
int nddcs ()
int nducs ()
bool start ()
 Called to enable drivers, etc for i/o devices.
bool stop ()
 Called to disable drivers, etc for i/o devices.
bool set_format (unsigned int format)
 Specify Rx data format.
unsigned int format () const
 return current format
bool tune (int chan, db_base_sptr db, double target_freq, usrp_tune_result *result)
 High-level "tune" method. Works for the single channel case.
usrp_subdev_spec pick_rx_subdevice ()
 Select suitable Rx daughterboard.

Static Public Member Functions

static unsigned int make_format (int width=16, int shift=0, bool want_q=true, bool bypass_halfband=false)
static int format_width (unsigned int format)
static int format_shift (unsigned int format)
static bool format_want_q (unsigned int format)
static bool format_bypass_halfband (unsigned int format)

Protected Member Functions

 usrp_source_base (const std::string &name, gr_io_signature_sptr output_signature, int which_board, unsigned int decim_rate, int nchan, int mux, int mode, int fusb_block_size, int fusb_nblocks, const std::string fpga_filename, const std::string firmware_filename) throw (std::runtime_error)
virtual int ninput_bytes_reqd_for_noutput_items (int noutput_items)=0
 return number of usrp input bytes required to produce noutput items.
unsigned int sizeof_basic_sample () const
 number of bytes in a low-level sample
virtual void copy_from_usrp_buffer (gr_vector_void_star &output_items, int output_index, int output_items_available, int &output_items_produced, const void *usrp_buffer, int usrp_buffer_length, int &bytes_read)=0
 convert between native usrp format and output item format

Detailed Description

abstract interface to Universal Software Radio Peripheral Rx path (Rev 1)


Constructor & Destructor Documentation

usrp_source_base::usrp_source_base ( const std::string &  name,
gr_io_signature_sptr  output_signature,
int  which_board,
unsigned int  decim_rate,
int  nchan,
int  mux,
int  mode,
int  fusb_block_size,
int  fusb_nblocks,
const std::string  fpga_filename,
const std::string  firmware_filename 
) throw (std::runtime_error) [protected]
usrp_source_base::~usrp_source_base ( )

Member Function Documentation

long usrp_source_base::adc_freq ( ) const [inline]
long usrp_source_base::adc_rate ( ) const [inline]
virtual void usrp_source_base::copy_from_usrp_buffer ( gr_vector_void_star output_items,
int  output_index,
int  output_items_available,
int &  output_items_produced,
const void *  usrp_buffer,
int  usrp_buffer_length,
int &  bytes_read 
) [protected, pure virtual]

convert between native usrp format and output item format

Parameters:
[out]output_itemsstream(s) of output items
[in]output_indexstarting index in output_items
[in]output_items_availablenumber of empty items available at item[index]
[out]output_items_producednumber of items produced by copy
[in]usrp_buffersource buffer
[in]usrp_buffer_lengthnumber of bytes available in usrp_buffer
[out]bytes_readnumber of bytes read from usrp_buffer

The copy must consume all bytes available. That is, bytes_read must equal usrp_buffer_length.

Implemented in usrp_source_c, and usrp_source_s.

unsigned int usrp_source_base::decim_rate ( ) const
int usrp_source_base::determine_rx_mux_value ( usrp_subdev_spec  ss)
int usrp_source_base::determine_rx_mux_value ( usrp_subdev_spec  ss_a,
usrp_subdev_spec  ss_b 
)
unsigned int usrp_source_base::format ( ) const

return current format

static bool usrp_source_base::format_bypass_halfband ( unsigned int  format) [static]
static int usrp_source_base::format_shift ( unsigned int  format) [static]
static bool usrp_source_base::format_want_q ( unsigned int  format) [static]
static int usrp_source_base::format_width ( unsigned int  format) [static]
bool usrp_source_base::has_rx_halfband ( )
bool usrp_source_base::has_tx_halfband ( )
static unsigned int usrp_source_base::make_format ( int  width = 16,
int  shift = 0,
bool  want_q = true,
bool  bypass_halfband = false 
) [static]
int usrp_source_base::mux ( ) const
int usrp_source_base::nchannels ( ) const
int usrp_source_base::nddcs ( )
int usrp_source_base::nducs ( )
virtual int usrp_source_base::ninput_bytes_reqd_for_noutput_items ( int  noutput_items) [protected, pure virtual]

return number of usrp input bytes required to produce noutput items.

Implemented in usrp_source_c, and usrp_source_s.

int usrp_source_base::noverruns ( ) const [inline]
usrp_subdev_spec usrp_source_base::pick_rx_subdevice ( )

Select suitable Rx daughterboard.

double usrp_source_base::rx_freq ( int  channel) const
bool usrp_source_base::set_ddc_phase ( int  channel,
int  phase 
)

Set the digital down converter phase register.

Parameters:
channelwhich ddc channel [0, 3]
phase32-bit integer phase value.
bool usrp_source_base::set_decim_rate ( unsigned int  rate)

Set decimator rate. rate must be EVEN and in [8, 256].

The final complex sample rate across the USB is adc_freq () / decim_rate ()

bool usrp_source_base::set_format ( unsigned int  format)

Specify Rx data format.

Parameters:
formatformat specifier

Rx data format control register

3 2 1 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 +-----------------------------------------+-+-+---------+-------+ | Reserved (Must be zero) |B|Q| WIDTH | SHIFT | +-----------------------------------------+-+-+---------+-------+

SHIFT specifies arithmetic right shift [0, 15] WIDTH specifies bit-width of I & Q samples across the USB [1, 16] (not all valid) Q if set deliver both I & Q, else just I B if set bypass half-band filter.

Right now the acceptable values are:

B Q WIDTH SHIFT 0 1 16 0 0 1 8 8

More valid combos to come.

Default value is 0x00000300 16-bits, 0 shift, deliver both I & Q.

bool usrp_source_base::set_fpga_mode ( int  mode)

set fpga special modes

bool usrp_source_base::set_mux ( int  mux)
bool usrp_source_base::set_nchannels ( int  nchan)
bool usrp_source_base::set_rx_freq ( int  channel,
double  freq 
)

set the center frequency of the digital down converter.

channel must be 0. freq is the center frequency in Hz. It must be in the range [-FIXME, FIXME]. The frequency specified is quantized. Use rx_freq to retrieve the actual value used.

unsigned int usrp_source_base::sizeof_basic_sample ( ) const [protected]

number of bytes in a low-level sample

bool usrp_source_base::start ( ) [virtual]

Called to enable drivers, etc for i/o devices.

This allows a block to enable an associated driver to begin transfering data just before we start to execute the scheduler. The end result is that this reduces latency in the pipeline when dealing with audio devices, usrps, etc.

Reimplemented from gr_block.

bool usrp_source_base::stop ( ) [virtual]

Called to disable drivers, etc for i/o devices.

Reimplemented from gr_block.

bool usrp_source_base::tune ( int  chan,
db_base_sptr  db,
double  target_freq,
usrp_tune_result result 
)

High-level "tune" method. Works for the single channel case.

This method adjusts both the daughterboard LO and the DDC so that target_freq ends up at DC in the complex baseband samples.

Parameters:
chanwhich DDC channel we're controlling (almost always 0).
dbthe daughterboard we're controlling.
target_freqthe RF frequency we want at DC in the complex baseband.
[out]resultdetails how the hardware was configured.
Returns:
true iff everything was successful.
int usrp_source_base::work ( int  noutput_items,
gr_vector_const_void_star input_items,
gr_vector_void_star output_items 
) [virtual]

just like gr_block::general_work, only this arranges to call consume_each for you

The user must override work to define the signal processing code

Implements gr_sync_block.


The documentation for this class was generated from the following file: