diff options
Diffstat (limited to 'blocks/src/lib/op25_fsk4_slicer_fb.cc')
| -rw-r--r-- | blocks/src/lib/op25_fsk4_slicer_fb.cc | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/blocks/src/lib/op25_fsk4_slicer_fb.cc b/blocks/src/lib/op25_fsk4_slicer_fb.cc new file mode 100644 index 0000000..4fa9b03 --- /dev/null +++ b/blocks/src/lib/op25_fsk4_slicer_fb.cc @@ -0,0 +1,123 @@ +/* -*- Mode: C++ -*- */ + +/* + * Copyright 2010, KA1RBI + * + * This file is part of OP25. + * + * OP25 is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 3, or (at your option) + * any later version. + * + * OP25 is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public + * License for more details. + * + * You should have received a copy of the GNU General Public License + * along with OP25; see the file COPYING. If not, write to the Free + * Software Foundation, Inc., 51 Franklin Street, Boston, MA + * 02110-1301, USA. + */ + +/* + * config.h is generated by configure. It contains the results + * of probing for features, options etc. It should be the first + * file included in your .cc file. + */ +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include <op25_fsk4_slicer_fb.h> +#include <gr_io_signature.h> +#include <stdio.h> + +/* + * Create a new instance of op25_fsk4_slicer_fb and return + * a boost shared_ptr. This is effectively the public constructor. + */ +op25_fsk4_slicer_fb_sptr +op25_make_fsk4_slicer_fb(const std::vector<float> &slice_levels) +{ + return op25_fsk4_slicer_fb_sptr(new op25_fsk4_slicer_fb (slice_levels)); +} + +/* + * Specify constraints on number of input and output streams. + * This info is used to construct the input and output signatures + * (2nd & 3rd args to gr_block's constructor). The input and + * output signatures are used by the runtime system to + * check that a valid number and type of inputs and outputs + * are connected to this block. In this case, we accept + * only 1 input and 1 output. + */ +static const int MIN_IN = 1; // mininum number of input streams +static const int MAX_IN = 1; // maximum number of input streams +static const int MIN_OUT = 1; // minimum number of output streams +static const int MAX_OUT = 1; // maximum number of output streams + +/* + * The private constructor + */ +op25_fsk4_slicer_fb::op25_fsk4_slicer_fb(const std::vector<float> &slice_levels) + : gr_sync_block("fsk4_slicer_fb", + gr_make_io_signature(MIN_IN, MAX_IN, sizeof(float)), + gr_make_io_signature(MIN_OUT, MAX_OUT, sizeof(unsigned char))) +{ + d_slice_levels[0] = slice_levels[0]; + d_slice_levels[1] = slice_levels[1]; + d_slice_levels[2] = slice_levels[2]; + d_slice_levels[3] = slice_levels[3]; +} + +/* + * Our virtual destructor. + */ +op25_fsk4_slicer_fb::~op25_fsk4_slicer_fb() +{ + // nothing else required in this example +} + +int +op25_fsk4_slicer_fb::work(int noutput_items, + gr_vector_const_void_star &input_items, + gr_vector_void_star &output_items) +{ + const float *in = (const float *) input_items[0]; + unsigned char *out = (unsigned char *) output_items[0]; + + for(int i = 0; i < noutput_items; i++){ +#if 0 + if(in[i] < -2.0) { + out[i] = 3; + } else if(in[i] < 0.0) { + out[i] = 2; + } else if(in[i] < 2.0) { + out[i] = 0; + } else { + out[i] = 1; + } +#endif + uint8_t dibit; + float sym = in[i]; + if(d_slice_levels[3] < 0) { + dibit = 1; + if(d_slice_levels[3] <= sym && sym < d_slice_levels[0]) + dibit = 3; + } else { + dibit = 3; + if(d_slice_levels[2] <= sym && sym < d_slice_levels[3]) + dibit = 1; + } + if(d_slice_levels[0] <= sym && sym < d_slice_levels[1]) + dibit = 2; + if(d_slice_levels[1] <= sym && sym < d_slice_levels[2]) + dibit = 0; + out[i] = dibit; + } + + // Tell runtime system how many output items we produced. + return noutput_items; +} |