ardupilot/libraries/AP_AIS/AP_AIS.h

140 lines
4.7 KiB
C++

/*
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 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include <AP_Param/AP_Param.h>
#include <AP_SerialManager/AP_SerialManager.h>
#include <AP_Common/AP_ExpandingArray.h>
#ifndef HAL_AIS_ENABLED
#define HAL_AIS_ENABLED !HAL_MINIMIZE_FEATURES
#endif
#if HAL_AIS_ENABLED
#define AIVDM_BUFFER_SIZE 10
#define AIVDM_PAYLOAD_SIZE 65
class AP_AIS
{
public:
AP_AIS();
/* Do not allow copies */
AP_AIS(const AP_AIS &other) = delete;
AP_AIS &operator=(const AP_AIS&) = delete;
// return true if AIS is enabled
bool enabled() const { return AISType(_type.get()) != AISType::NONE; }
// Initialize the AIS object and prepare it for use
void init();
// update AIS, expected to be called at 20hz
void update();
// send mavlink AIS message
void send(mavlink_channel_t chan);
// parameter block
static const struct AP_Param::GroupInfo var_info[];
private:
// parameters
AP_Int8 _type; // type of AIS receiver
AP_Int16 _max_list; // maximum number of vessels to track at once
AP_Int16 _time_out; // time in seconds that a vessel will be dropped from the list
AP_Int16 _log_options; // logging options bitmask
enum class AISType {
NONE = 0,
NMEA = 1,
};
enum options {
AIS_OPTIONS_LOG_ALL_RAW = 1<<0,
AIS_OPTIONS_LOG_UNSUPPORTED_RAW = 1<<1,
AIS_OPTIONS_LOG_DECODED = 1<<2,
};
struct AIVDM {
uint8_t num;
uint8_t total;
uint8_t ID;
char payload[AIVDM_PAYLOAD_SIZE];
};
AIVDM _incoming;
AIVDM _AIVDM_buffer[AIVDM_BUFFER_SIZE];
struct ais_vehicle_t {
mavlink_ais_vessel_t info;
uint32_t last_update_ms; // last time this was refreshed, allows timeouts
uint32_t last_send_ms; // last time this message was sent via mavlink, stops us spamming the link
};
// list of the vessels that are being tracked
AP_ExpandingArray<ais_vehicle_t> _list {8};
AP_HAL::UARTDriver *_uart;
uint16_t _send_index; // index of the last vessel send over mavlink
// removed the given index from the AIVDM buffer shift following elements
void buffer_shift(uint8_t i);
// find vessel in existing list, if not then return new index if possible
bool get_vessel_index(uint32_t mmsi, uint16_t &index, uint32_t lat = 0, uint32_t lon = 0) WARN_IF_UNUSED;
void clear_list_item(uint16_t index);
// decode the payload
bool payload_decode(const char *payload) WARN_IF_UNUSED;
// decode specific message types
bool decode_position_report(const char *payload, uint8_t type) WARN_IF_UNUSED;
bool decode_base_station_report(const char *payload) WARN_IF_UNUSED;
bool decode_static_and_voyage_data(const char *payload) WARN_IF_UNUSED;
// read the specified bits from the char array each char giving 6 bits
void get_char(const char *payload, char *array, uint16_t low, uint16_t high);
uint32_t get_bits(const char *payload, uint16_t low, uint16_t high);
int32_t get_bits_signed(const char *payload, uint16_t low, uint16_t high);
// un-encode the ASCII payload armoring
uint8_t payload_char_decode(const char c);
// log a raw AIVDM message
void log_raw(const AIVDM *msg);
// try and decode NMEA message
bool decode(char c) WARN_IF_UNUSED;
// decode each term
bool decode_latest_term() WARN_IF_UNUSED;
// convert from char to hex value for checksum
int16_t char_to_hex(char a);
// varables for decoding NMEA sentence
char _term[AIVDM_PAYLOAD_SIZE]; // buffer for the current term within the current sentence
uint8_t _term_offset; // offset within the _term buffer where the next character should be placed
uint8_t _term_number; // term index within the current sentence
uint8_t _checksum; // checksum accumulator
bool _term_is_checksum; // current term is the checksum
bool _sentence_valid; // is current sentence valid so far
bool _sentence_done; // true if this sentence has already been decoded
};
#endif // HAL_AIS_ENABLED