apb.cpp

来自「提取各种NEMA0183格式数据的类编程。」· C++ 代码 · 共 311 行

/*
** Author: Samuel R. Blackburn
** Internet: [e-mail]
**
** Copyright, 1996-2005, Samuel R. Blackburn
**
** "You can get credit for something or get it done, but not both."
** Dr. Richard Garwin
**
** BSD License follows.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions
** are met:
**
** Redistributions of source code must retain the above copyright notice,
** this list of conditions and the following disclaimer. Redistributions
** in binary form must reproduce the above copyright notice, this list
** of conditions and the following disclaimer in the documentation and/or
** other materials provided with the distribution. Neither the name of
** the WFC nor the names of its contributors may be used to endorse or
** promote products derived from this software without specific prior
** written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**
** $Workfile: apb.cpp $
** $Revision: 5 $
** $Modtime: 10/10/98 2:41p $
*/

#include "nmea0183.h"
#pragma hdrstop

#if defined( _DEBUG ) && defined( _INC_CRTDBG )
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#define new DEBUG_NEW
#endif // _DEBUG

APB::APB()
{
   Mnemonic = TEXT( "APB" );
   Empty();
}

APB::~APB()
{
   Mnemonic.Empty();
   Empty();
}

void APB::Empty( void )
{
   CrossTrackErrorMagnitude = 0.0;
   DirectionToSteer         = LR_Unknown;
   CrossTrackUnits.Empty();
   To.Empty();
   IsArrivalCircleEntered   = NMEA_Unknown;
   IsPerpendicular          = NMEA_Unknown;
   FAAMode                  = FAAModeUnknown;
}

BOOL APB::Parse( const SENTENCE& sentence )
{
   CString field_data;

   /*
   ** APB - Autopilot Sentence "B"
   **                                         13    15
   **        1 2 3   4 5 6 7 8   9 10   11  12|   14|
   **        | | |   | | | | |   | |    |   | |   | |
   ** $--APB,A,A,x.x,a,N,A,A,x.x,a,c--c,x.x,a,x.x,a*hh<CR><LF>
   **
   **  1) Status
   **     V = LORAN-C Blink or SNR warning
   **     V = general warning flag or other navigation systems when a reliable
   **         fix is not available
   **  2) Status
   **     V = Loran-C Cycle Lock warning flag
   **     A = OK or not used
   **  3) Cross Track Error Magnitude
   **  4) Direction to steer, L or R
   **  5) Cross Track Units, N = Nautical Miles
   **  6) Status
   **     A = Arrival Circle Entered
   **  7) Status
   **     A = Perpendicular passed at waypoint
   **  8) Bearing origin to destination
   **  9) M = Magnetic, T = True
   ** 10) Destination Waypoint ID
   ** 11) Bearing, present position to Destination
   ** 12) M = Magnetic, T = True
   ** 13) Heading to steer to destination waypoint
   ** 14) M = Magnetic, T = True
   ** 15) Checksum or FAA Mode Indicator
   ** 16) Checksum if FAA Mode Indicator is present
   */

   // 2005-02-24, according to http://gpsd.berlios.de/NMEA.txt, NMEA added another field to the sentence

   /*
   ** First we must determine the number of data fields then check the checksum...
   */

   const NMEA0183_BOOLEAN checksum_is_bad = sentence.IsChecksumBad();

   if ( checksum_is_bad == True )
   {
      InvalidChecksum();
      return( FALSE );
   } 

   /*
   ** Line has already been checked for checksum validity
   */

   IsLoranBlinkOK                           = sentence.Boolean( 1 );
   IsLoranCCycleLockOK                      = sentence.Boolean( 2 );
   CrossTrackErrorMagnitude                 = sentence.Double( 3 );
   DirectionToSteer                         = sentence.LeftOrRight( 4 );
   CrossTrackUnits                          = sentence.Field( 5 );
   IsArrivalCircleEntered                   = sentence.Boolean( 6 );
   IsPerpendicular                          = sentence.Boolean( 7 );
   BearingOriginToDestination               = sentence.Double( 8 );
   BearingOriginToDestinationUnits          = sentence.Field( 9 );
   To                                       = sentence.Field( 10 );
   BearingPresentPositionToDestination      = sentence.Double( 11 );
   BearingPresentPositionToDestinationUnits = sentence.Field( 12 );
   HeadingToSteer                           = sentence.Double( 13 );
   HeadingToSteerUnits                      = sentence.Field( 14 );

   const int checksum_field_number = sentence.ChecksumFieldNumber();

   if ( checksum_field_number == 16 )
   {
      FAAMode = sentence.FAAMode( 15 );
   }
   else
   {
      FAAMode = FAAModeUnknown;
   }

   return( TRUE );
}

CString APB::ToText( void ) const
{
   CString return_string;

   return_string += "Destination ";
   return_string += To;

   if ( DirectionToSteer == Left )
   {
      return_string += " Steer Left";
   }
   else if ( DirectionToSteer == Right )
   {
      return_string += " Steer Right";
   }

   CString temp_string;

   temp_string.Format( "%.2f", BearingPresentPositionToDestination );

   return_string += ", Bearing ";
   return_string += temp_string;
   return_string += " degrees ";

   if ( BearingPresentPositionToDestinationUnits.Compare( "T" ) == 0 )
   {
      return_string += "True";
   }
   else if ( BearingPresentPositionToDestinationUnits.Compare( "M" ) == 0 )
   {
      return_string += "Magnetic";
   }
   else
   {
      return_string += "Unknown";
   }

   temp_string.Format( "%.2f", HeadingToSteer );

   if ( HeadingToSteerUnits.GetLength() > 0 )
   {
      return_string += TEXT( ", Steer to Heading " );
      return_string += temp_string;

      if ( HeadingToSteerUnits.Compare( TEXT( "T" ) ) == 0 )
      {
         return_string += TEXT( "True" );
      }
      else if ( HeadingToSteerUnits.Compare( TEXT( "M" ) ) == 0 )
      {
         return_string += TEXT( "Magnetic" );
      }
      else
      {
         return_string += TEXT( "Unknown" );
      }
   }

   return_string += " ";

   if ( FAAMode != FAAModeUnknown )
   {
      switch( FAAMode )
      {
         case Autonomous:

            return_string += TEXT( "FAA Mode: Autonomous" );
		      break;

         case Differential:

	         return_string += TEXT( "FAA Mode: Differential" );
		      break;

         case Estimated:

	         return_string += TEXT( "FAA Mode: Estimated" );
		      break;

         case Manual:

	         return_string += TEXT( "FAA Mode: Manual" );
		      break;

         case Simulated:

	         return_string += TEXT( "FAA Mode: Simulated" );
		      break;

         case NotValid:

	         return_string += TEXT( "FAA Mode: Data not valie" );
		      break;

         case Invalid:

	         return_string += TEXT( "FAA Mode: Data INVALID" );
		      break;
      }
   }

   return_string.TrimLeft();
   return_string.TrimRight();

   return( return_string );
}

BOOL APB::Write( SENTENCE& sentence )
{
   /*
   ** Let the parent do its thing
   */
   
   RESPONSE::Write( sentence );

   sentence += IsLoranBlinkOK;
   sentence += IsLoranCCycleLockOK;
   sentence += CrossTrackErrorMagnitude;
   sentence += DirectionToSteer;
   sentence += CrossTrackUnits;
   sentence += IsArrivalCircleEntered;
   sentence += IsPerpendicular;
   sentence += BearingOriginToDestination;
   sentence += BearingOriginToDestinationUnits;
   sentence += To;
   sentence += BearingPresentPositionToDestination;
   sentence += BearingPresentPositionToDestinationUnits;
   sentence += HeadingToSteer;
   sentence += HeadingToSteerUnits;

   sentence.Finish();

   return( TRUE );
}

const APB& APB::operator = ( const APB& source )
{
   IsLoranBlinkOK                           = source.IsLoranBlinkOK;
   IsLoranCCycleLockOK                      = source.IsLoranCCycleLockOK;
   CrossTrackErrorMagnitude                 = source.CrossTrackErrorMagnitude;
   DirectionToSteer                         = source.DirectionToSteer;
   CrossTrackUnits                          = source.CrossTrackUnits;
   IsArrivalCircleEntered                   = source.IsArrivalCircleEntered;
   IsPerpendicular                          = source.IsPerpendicular;
   BearingOriginToDestination               = source.BearingOriginToDestination;
   BearingOriginToDestinationUnits          = source.BearingOriginToDestinationUnits;
   To                                       = source.To;
   BearingPresentPositionToDestination      = source.BearingPresentPositionToDestination;
   BearingPresentPositionToDestinationUnits = source.BearingPresentPositionToDestinationUnits;
   HeadingToSteer                           = source.HeadingToSteer;
   HeadingToSteerUnits                      = source.HeadingToSteerUnits;

   return( *this );
}