NMEA

static void _gps_task(void *arg) {
    u8_t size;
    u8_t marker;
    u8_t type[5];
    u8_t body[128];
	
		nmeaINFO info;          //GPS解码后得到的信息
    nmeaPARSER parser;      //解码时使用的数据结构  

		
    nmea_zero_INFO(&info);	//初始化NMEA数据结构体
    nmea_parser_init(&parser);//初始化NMEA数据结构体
	
    _gps_init();
    os_driver_ioctl(_gps_dev, SET_EMPTY_FIFO, 0); // 清空接收缓冲队列

    OS_RTT_printf(0, "GPS Task implementation \n");

    while (1) {

        memset((void *) &marker, 0, sizeof(marker));
        size = _gps_read(&marker, 1);
        if (size == 0) {
            msleep(200);
            continue;
        }

        if (marker != '$') continue;

        memset((void *) &type, 0, sizeof(type));
        _gps_read((u8_t *) type, 5);
        OS_RTT_printf(0, "Type:%s \n", type);
        if (type[0] != 'G' || type[1] != 'N' || type[2] != 'Z' || type[3] != 'D' || type[4] != 'A') {
            continue;
        } else {
            _gps_read((u8_t *) body, 27);
            OS_RTT_printf(0, "Rec:%s \n", body);
        }
    }
}