almanac.c

非常好用的gps数据读写接口

/***************************************************************************
                     almanac.c  -  almanac stuff
                             -------------------
    begin                : So M鋜 21 17:50:31 CET 2004
    copyright            : (C) 2004 by Dennis Real
    email                : [e-mail]
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   This program 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 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/

#include <stdio.h>
#include "def.h"
#include "llayer.h"
#include "convert.h"
#include "datatypes.h"

D501_Almanac_Type getAlmanacD501(char *gcommand, int s)
{

	D501_Almanac_Type singlesat;

	singlesat.wn=0;
	singlesat.toa=0;
	singlesat.af0=0;
	singlesat.af1=0;
	singlesat.e=0;
	singlesat.sqrta=0;
	singlesat.m0=0;
	singlesat.w=0;
	singlesat.omg0=0;
	singlesat.odot=0;
	singlesat.i=0;
	singlesat.hlth=0;

	if ( (s==48) && (((unsigned char)gcommand[1]+2)==s) && (gcommand[0]==31) )
	{
		singlesat.wn=(int)((BYTE)(gcommand[2])+((BYTE)(gcommand[3])*256));
		singlesat.toa=char2float(&gcommand[4]);
		singlesat.af0=char2float(&gcommand[8]);
		singlesat.af1=char2float(&gcommand[12]);
		singlesat.e=char2float(&gcommand[16]);
		singlesat.sqrta=char2float(&gcommand[20]);
		singlesat.m0=char2float(&gcommand[24]);
		singlesat.w=char2float(&gcommand[28]);
		singlesat.omg0=char2float(&gcommand[32]);
		singlesat.odot=char2float(&gcommand[36]);
		singlesat.i=char2float(&gcommand[40]);
		singlesat.hlth=(BYTE)gcommand[44];
	}

	return singlesat;
}


/*	get infos for each satellite and store in global satinfo[n]	*/
void getAllAlmanac(int tty)
{
	unsigned int s; // t=0;
	char *gcommand;
      
	int z=0, anz;
	D501_Almanac_Type singlesat;      
	extern Almanac_Type satinfo[];

  /* abort current transfer */
  SendCommand(tty, "\x0a\x02\x00\x00", 4);
	gcommand=GetCommand(tty, &s);

	/* start transfer */	
	SendCommand(tty, "\x0a\x02\x01\x00", 4);
	gcommand=GetCommand(tty, &s);		//ack

	if ( gcommand==NULL )
	{
		return;	
	}
	
	gcommand=GetCommand(tty, &s);		//27 pid records
	anz=gcommand[2];

	while( (z<anz) && (z<ANZSAT) )
	{
		ACKCommand(tty, gcommand, s);
    gcommand=GetCommand(tty, &s);

		singlesat=getAlmanacD501(gcommand, s);

		satinfo[z].wn=singlesat.wn;
		satinfo[z].toa=singlesat.toa;
		satinfo[z].af0=singlesat.af0;
		satinfo[z].af1=singlesat.af1;
		satinfo[z].e=singlesat.e;
		satinfo[z].sqrta=singlesat.sqrta;
		satinfo[z].m0=singlesat.m0;
		satinfo[z].w=singlesat.w;
		satinfo[z].omg0=singlesat.omg0;
		satinfo[z].odot=singlesat.odot;
		satinfo[z].wn=singlesat.wn;
		satinfo[z].i=singlesat.i;
		satinfo[z].hlth=singlesat.hlth;

/*
#ifdef DEBUG
		fprintf(stderr, "%d %f %f %f %f %f %f %f %f %f %f %d",
		singlesat.wn,
		singlesat.toa,
		singlesat.af0,
		singlesat.af1,
		singlesat.e=0,
		singlesat.sqrta,
		singlesat.m0,
		singlesat.w,
		singlesat.omg0,
		singlesat.odot,
		singlesat.i,
		singlesat.hlth);
#endif
*/

		z++;	
  }
                              
	ACKCommand(tty, gcommand, s);
	gcommand=GetCommand(tty, &s);	//12 xfer cmpl 


}