an_packet_printer.h

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/*!
 * \file an_packet_printer.h
 * \brief Interface of a class that prints PVT solutions in a serial device
 * following a custom version of the Advanced Navigation Packet Protocol
 * \author Carles Fernandez-Prades, 2021. cfernandez(at)cttc.es
 * \author Miguel Angel Gomez Lopez, 2021. gomezlma(at)inta.es
 *
 *
 * -----------------------------------------------------------------------------
 *
 * GNSS-SDR is a Global Navigation Satellite System software-defined receiver.
 * This file is part of GNSS-SDR.
 *
 * Copyright (C) 2010-2021  (see AUTHORS file for a list of contributors)
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 * -----------------------------------------------------------------------------
 */


#ifndef GNSS_SDR_AN_PACKET_PRINTER_H
#define GNSS_SDR_AN_PACKET_PRINTER_H

#include "gnss_synchro.h"
#include <array>
#include <chrono>
#include <cstddef>
#include <cstdint>
#include <map>
#include <string>

/** \addtogroup PVT
 * \{ */
/** \addtogroup PVT_libs
 * \{ */

class Rtklib_Solver;

struct sdr_gnss_packet_t
{
    uint8_t nsvfix;              // number of sats used in PVT fix
    uint8_t gps_satellites;      // number of tracked GPS satellites
    uint8_t galileo_satellites;  // number of tracked Galileo satellites
    uint32_t microseconds;       // from start of receiver operation
    double latitude;             // in [rad]
    double longitude;            // in [rad]
    double height;               // in [m]
    float velocity[3];           // North, East, Down, in [m/s]

    struct
    {
        uint8_t prn;      // PRN ID. Galileo sats expressed as PRN + 100
        uint8_t snr;      // in [dB-Hz]
        int16_t doppler;  // in [Hz], saturates at +32767 / -32768 Hz
    } sats[6];

    uint32_t reserved;
    uint16_t status;
};


struct an_packet_t
{
    uint8_t header[4];
    uint8_t data[73];  // SDR_GNSS_PACKET_LENGTH
};


/*!
 * \brief class that prints PVT solutions in a serial device following a custom
 * version of the Advanced Navigation Packet Protocol.
 */
class An_Packet_Printer
{
public:
    /*!
     * \brief Default constructor.
     */
    explicit An_Packet_Printer(const std::string& an_dump_devname);

    /*!
     * \brief Default destructor.
     */
    ~An_Packet_Printer();

    /*!
     * \brief Print AN packet to the initialized device.
     */
    bool print_packet(const Rtklib_Solver* const pvt_data, const std::map<int, Gnss_Synchro>& gnss_observables_map);

    /*!
     * \brief Close serial port. Also done in the destructor, this is only
     * for testing.
     */
    void close_serial() const;

private:
    const std::array<uint16_t, 256> d_crc16_table = {
        {0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7, 0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef, 0x1231, 0x0210, 0x3273,
            0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6, 0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de, 0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485, 0xa56a, 0xb54b, 0x8528,
            0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d, 0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4, 0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc, 0x48c4, 0x58e5, 0x6886,
            0x78a7, 0x0840, 0x1861, 0x2802, 0x3823, 0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b, 0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12, 0xdbfd, 0xcbdc, 0xfbbf,
            0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a, 0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41, 0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49, 0x7e97, 0x6eb6, 0x5ed5,
            0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70, 0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78, 0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f, 0x1080, 0x00a1, 0x30c2,
            0x20e3, 0x5004, 0x4025, 0x7046, 0x6067, 0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e, 0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256, 0xb5ea, 0xa5cb, 0x95a8,
            0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d, 0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405, 0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c, 0x26d3, 0x36f2, 0x0691,
            0x16b0, 0x6657, 0x7676, 0x4615, 0x5634, 0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab, 0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3, 0xcb7d, 0xdb5c, 0xeb3f,
            0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a, 0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92, 0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9, 0x7c26, 0x6c07, 0x5c64,
            0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1, 0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8, 0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0}};

    const size_t SDR_GNSS_PACKET_LENGTH = 73;
    const uint8_t SDR_GNSS_PACKET_ID = 201;

    int init_serial(const std::string& serial_device);
    void update_sdr_gnss_packet(sdr_gnss_packet_t* _packet, const Rtklib_Solver* const pvt, const std::map<int, Gnss_Synchro>& gnss_observables_map) const;
    void encode_gnss_cttc_packet(sdr_gnss_packet_t* sdr_gnss_packet, an_packet_t* _packet) const;
    uint16_t calculate_crc16(const void* data, uint16_t length) const;
    uint8_t calculate_header_lrc(const uint8_t* data) const;
    void an_packet_encode(an_packet_t* an_packet) const;
    void encode_sdr_gnss_packet(sdr_gnss_packet_t* sdr_gnss_packet, an_packet_t* _packet) const;
    void LSB_bytes_to_array(void* _in, int offset, uint8_t* _out, uint8_t var_size) const;

    std::chrono::time_point<std::chrono::system_clock> d_start;
    std::string d_an_devname;
    int d_an_dev_descriptor;  // serial device descriptor (i.e. COM port)
};

/** \} */
/** \} */
#endif  // GNSS_SDR_AN_PACKET_PRINTER_H