gps_average.c

来自「This a support library and assorted samp」· C语言 代码 · 共 42 行

#include "as_gps.h"

int main(int argc, char **argv)
{
  void *data;
  double lat, lgt;
  unsigned fix, read_count = 0;

  if(as_gps_open("/dev/gps"))
  {
    printf("Can't open device\n");
    exit(1);
  }

  while(1)
  {
    unsigned char result = as_gps_handle_input(&data);

    if(result == AS_GPS_RCV_POSITION_DATA) 
    {
      AS_GPS_PositionData *pos = (AS_GPS_PositionData *)data;

      fix = pos->status & 0x0f;
      if(fix == 3 || fix == 4) /* at least a 2D or 3D fix */
      {
        lat = (pos->lat + ((double)read_count * lat)) /
                          ((double)read_count+1);

        lgt = (pos->lgt + ((double)read_count * lgt)) /
                          ((double)read_count+1);

        printf("%5u: Lat: %3.16f, Lgt: %3.16f\n", read_count, lat, lgt);
        read_count++;
      }
    }
    free(data);
  }

  as_gps_close(); 
}