gr_oscope_guts.h

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/* -*- c++ -*- */
/*
 * Copyright 2003,2005 Free Software Foundation, Inc.
 * 
 * This file is part of GNU Radio
 * 
 * GNU Radio 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.
 * 
 * GNU Radio 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 GNU Radio; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */


#ifndef INCLUDED_GR_OSCOPE_GUTS_H
#define INCLUDED_GR_OSCOPE_GUTS_H

#include <gr_trigger_mode.h>
#include <gr_msg_queue.h>

/*!
 * \brief guts of oscilloscope trigger and buffer module
 *
 * This module processes sets of samples provided the \p process_sample
 * method.  When appropriate given the updateRate, sampleRate and
 * trigger conditions, process_sample will periodically write output
 * records of captured data to output_fd.  For each trigger event,
 * nchannels records will be written.  Each record consists of
 * get_samples_per_output_record binary floats.  The trigger instant
 * occurs at the 1/2 way point in the buffer.  Thus, output records
 * consist of 50% pre-trigger data and 50% post-trigger data.
 */

class gr_oscope_guts {
public:
  static const int      MAX_CHANNELS = 8;
private:
  enum scope_state      { HOLD_OFF, LOOK_FOR_TRIGGER, POST_TRIGGER };

  int                   d_nchannels;            // how many channels
  gr_msg_queue_sptr     d_msgq;                 // message queue we stuff output records into
  gr_trigger_mode       d_trigger_mode;
  gr_trigger_slope      d_trigger_slope;
  int                   d_trigger_channel;      // which channel to watch for trigger condition
  double                d_sample_rate;          // input sample rate in Hz
  double                d_update_rate;          // approx freq to produce an output record (Hz)
  double                d_trigger_level;

  int                   d_obi;                  // output buffer index 
  float                *d_buffer[MAX_CHANNELS];

  scope_state           d_state;
  int                   d_decimator_count;
  int                   d_decimator_count_init;
  int                   d_hold_off_count;
  int                   d_hold_off_count_init;
  int                   d_pre_trigger_count;
  int                   d_post_trigger_count;
  int                   d_post_trigger_count_init;
  float                 d_trigger_off;                  //%sample trigger is off

  // NOT IMPLEMENTED
  gr_oscope_guts (const gr_oscope_guts &rhs);                   // no copy constructor
  gr_oscope_guts &operator= (const gr_oscope_guts &rhs);        // no assignment operator

  void trigger_changed ();
  void update_rate_or_decimation_changed ();
  bool found_trigger ();        // returns true if found
  void write_output_records ();

  void enter_hold_off ();                       // called on state entry
  void enter_look_for_trigger ();
  void enter_post_trigger ();

public:
  // CREATORS
  gr_oscope_guts (double sample_rate, gr_msg_queue_sptr msgq);
  ~gr_oscope_guts ();

  // MANIPULATORS

  /*!
   * \p channel_data points to nchannels float values.  These are the values
   * for each channel at this sample time.
   */
  void process_sample (const float *channel_data);

  bool set_update_rate (double update_rate);
  bool set_decimation_count (int decimation_count);
  bool set_trigger_channel (int channel);
  bool set_trigger_mode (gr_trigger_mode mode);
  bool set_trigger_slope (gr_trigger_slope slope);
  bool set_trigger_level (double trigger_level);
  bool set_trigger_level_auto ();                               // set to 50% level
  bool set_sample_rate(double sample_rate);
  bool set_num_channels(int nchannels);


  // ACCESSORS
  int num_channels () const;
  double sample_rate () const;
  double update_rate () const;
  int get_decimation_count () const;
  int get_trigger_channel () const;
  gr_trigger_mode get_trigger_mode () const;
  gr_trigger_slope get_trigger_slope () const;
  double get_trigger_level () const;

  // # of samples written to each output record.
  int get_samples_per_output_record () const;
};

#endif /* INCLUDED_GR_OSCOPE_GUTS_H */