code: function PositionObj (data) {
      this.msg    = parseInt (data.cmd);
      this.lat    = parseFloat(data.lat);
      this.lon    = parseFloat(data.lon);
      this.sog    = parseFloat(data.sog)   || 0;
      this.cog    = parseFloat(data.cog)   || 0;
      this.alt    = parseFloat(data.alt)   || 0;
      this.moved  = parseInt(data.moved)   || -1;
      this.elapsed= parseInt(data.elapsed) || -1;
      this.valid  = parseInt(+data.valid);
      this.acquired_at  = data.acquired_at;
      this.gpsdate= data.date;
  }
docs: small object to keep track of last position in ram