GNU Radio 2.x: gr_check_lfsr_32k_s.h Source File

Main Page | Modules | Namespace List | Class Hierarchy | Class List | File List | Class Members | File Members

# gr_check_lfsr_32k_s.h

Go to the documentation of this file.

    00001 /* -*- c++ -*- */
    00002 /*
    00003  * Copyright 2004 Free Software Foundation, Inc.
    00004  *
    00005  * This file is part of GNU Radio
    00006  *
    00007  * GNU Radio is free software; you can redistribute it and/or modify
    00008  * it under the terms of the GNU General Public License as published by
    00009  * the Free Software Foundation; either version 2, or (at your option)
    00010  * any later version.
    00011  *
    00012  * GNU Radio is distributed in the hope that it will be useful,
    00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
    00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    00015  * GNU General Public License for more details.
    00016  *
    00017  * You should have received a copy of the GNU General Public License
    00018  * along with GNU Radio; see the file COPYING.  If not, write to
    00019  * the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
    00020  * Boston, MA 02111-1307, USA.
    00021  */
    00022 #ifndef INCLUDED_GR_CHECK_LFSR_32K_S_H
    00023 #define INCLUDED_GR_CHECK_LFSR_32K_S_H
    00024
    00025 #include <gr_sync_block.h>
    00026 #include <gri_lfsr_32k.h>
    00027
    00028
    00029 class gr_check_lfsr_32k_s;
    00030 typedef boost::shared_ptr<gr_check_lfsr_32k_s> gr_check_lfsr_32k_s_sptr;
    00031
    00032 gr_check_lfsr_32k_s_sptr gr_make_check_lfsr_32k_s ();
    00033
    00041 class gr_check_lfsr_32k_s : public gr_sync_block
    00042 {
    00043   friend gr_check_lfsr_32k_s_sptr gr_make_check_lfsr_32k_s ();
    00044
    00045   enum state {
    00046     SEARCHING,          // searching for synchronization
    00047     MATCH0,
    00048     MATCH1,
    00049     MATCH2,
    00050     LOCKED              // is locked
    00051   };
    00052
    00053   state                 d_state;
    00054   unsigned int          d_history;              // bitmask of decisions
    00055
    00056   long                  d_ntotal;               // total number of shorts
    00057   long                  d_nright;               // # of correct shorts
    00058   long                  d_runlength;            // # of correct shorts in a row
    00059
    00060   static const int BUFSIZE = 2048 - 1;          // ensure pattern isn't packet aligned
    00061   int                   d_index;
    00062   unsigned short        d_buffer[BUFSIZE];
    00063
    00064
    00065   gr_check_lfsr_32k_s ();
    00066
    00067   void enter_SEARCHING ();
    00068   void enter_MATCH0 ();
    00069   void enter_MATCH1 ();
    00070   void enter_MATCH2 ();
    00071   void enter_LOCKED ();
    00072
    00073   void right (){
    00074     d_history = (d_history << 1) | 0x1;
    00075     d_nright++;
    00076     d_runlength++;
    00077   }
    00078
    00079   void wrong (){
    00080     d_history = (d_history << 1) | 0x0;
    00081     d_runlength = 0;
    00082   }
    00083
    00084   bool right_three_times () { return (d_history & 0x7) == 0x7; }
    00085   bool wrong_three_times () { return (d_history & 0x7) == 0x0; }
    00086
    00087   void log_error (unsigned short expected, unsigned short actual);
    00088
    00089  public:
    00090
    00091   int work (int noutput_items,
    00092             gr_vector_const_void_star &input_items,
    00093             gr_vector_void_star &output_items);
    00094
    00095   long ntotal () const { return d_ntotal; }
    00096   long nright () const { return d_nright; }
    00097   long runlength () const { return d_runlength; }
    00098
    00099 };
    00100
    00101
    00102 #endif /* INCLUDED_GR_CHECK_LFSR_32K_S_H */