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   1 /* -*- c++ -*- */
   2 /*
   3  * Copyright 2004,2006 Free Software Foundation, Inc.
   4  *
   5  * This file is part of GNU Radio
   6  *
   7  * GNU Radio is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 3, or (at your option)
  10  * any later version.
  11  *
  12  * GNU Radio is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with GNU Radio; see the file COPYING.  If not, write to
  19  * the Free Software Foundation, Inc., 51 Franklin Street,
  20  * Boston, MA 02110-1301, USA.
  21  */
  22
  23 #ifdef HAVE_CONFIG_H
  24 #include "config.h"
  25 #endif
  26
  27 #include <usrp_source_c.h>
  28 #include <gr_io_signature.h>
  29 #include <usrp_standard.h>
  30 #include <usrp_bytesex.h>
  31
  32 static const int NBASIC_SAMPLES_PER_ITEM = 2;   // I & Q
  33
  34 usrp_source_c_sptr
  35 usrp_make_source_c (int which_board,
  36                      unsigned int decim_rate,
  37                      int nchan,
  38                      int mux,
  39                      int mode,
  40                      int fusb_block_size,
  41                      int fusb_nblocks,
  42                      const std::string fpga_filename,
  43                      const std::string firmware_filename
  44                      ) throw (std::runtime_error)
  45 {
  46   return usrp_source_c_sptr (new usrp_source_c (which_board,
  47                                                   decim_rate,
  48                                                   nchan,
  49                                                   mux,
  50                                                   mode,
  51                                                   fusb_block_size,
  52                                                   fusb_nblocks,
  53                                                   fpga_filename,
  54                                                   firmware_filename
  55                                                   ));
  56 }
  57
  58
  59 usrp_source_c::usrp_source_c (int which_board,
  60                                 unsigned int decim_rate,
  61                                 int nchan,
  62                                 int mux,
  63                                 int mode,
  64                                 int fusb_block_size,
  65                                 int fusb_nblocks,
  66                                 const std::string fpga_filename,
  67                                 const std::string firmware_filename
  68                                 ) throw (std::runtime_error)
  69   : usrp_source_base ("usrp_source_c",
  70                        gr_make_io_signature (1, 1, sizeof (gr_complex)),
  71                        which_board, decim_rate, nchan, mux, mode,
  72                        fusb_block_size, fusb_nblocks,
  73                        fpga_filename, firmware_filename)
  74 {
  75 }
  76
  77 usrp_source_c::~usrp_source_c ()
  78 {
  79   // NOP
  80 }
  81
  82 int
  83 usrp_source_c::ninput_bytes_reqd_for_noutput_items (int noutput_items)
  84 {
  85   return noutput_items * NBASIC_SAMPLES_PER_ITEM * sizeof_basic_sample();
  86 }
  87
  88 /*
  89  * Convert interleaved 8 or 16-bit I & Q from usrp buffer into a single
  90  * complex output stream.
  91  */
  92 void
  93 usrp_source_c::copy_from_usrp_buffer (gr_vector_void_star &output_items,
  94                                        int output_index,
  95                                        int output_items_available,
  96                                        int &output_items_produced,
  97                                        const void *usrp_buffer,
  98                                        int usrp_buffer_length,
  99                                        int &bytes_read)
 100 {
 101   gr_complex *out = &((gr_complex *) output_items[0])[output_index];
 102   unsigned sbs = sizeof_basic_sample();
 103   unsigned nusrp_bytes_per_item = NBASIC_SAMPLES_PER_ITEM * sbs;
 104
 105   int nitems = std::min (output_items_available,
 106                          (int)(usrp_buffer_length / nusrp_bytes_per_item));
 107
 108   signed char *s8 = (signed char *) usrp_buffer;
 109   short *s16 = (short *) usrp_buffer;
 110
 111   switch (sbs){
 112   case 1:
 113     for (int i = 0; i < nitems; i++){
 114       out[i] = gr_complex ((float)(s8[2*i+0] << 8), (float)(s8[2*i+1] << 8));
 115     }
 116     break;
 117
 118   case 2:
 119     for (int i = 0; i < nitems; i++){
 120       out[i] = gr_complex ((float) usrp_to_host_short(s16[2*i+0]),
 121                            (float) usrp_to_host_short(s16[2*i+1]));
 122     }
 123     break;
 124
 125   default:
 126     assert(0);
 127   }
 128
 129   output_items_produced = nitems;
 130   bytes_read = nitems * nusrp_bytes_per_item;
 131 }