ardupilot/libraries/AP_WindVane/AP_WindVane_NMEA.h

59 lines
1.8 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_WindVane_Backend.h"
class AP_WindVane_NMEA : public AP_WindVane_Backend
{
public:
// constructor
AP_WindVane_NMEA(AP_WindVane &frontend);
// initialization
void init(const AP_SerialManager& serial_manager) override;
// update state
void update_direction() override;
void update_speed() override;
private:
// pointer to serial uart
AP_HAL::UARTDriver *uart = nullptr;
// See if we can read in some data
void update();
// try and decode NMEA message
bool decode(char c);
// decode each term
bool decode_latest_term();
// convert from char to hex value for checksum
int16_t char_to_hex(char a);
// latest values read in
float _speed_ms;
float _wind_dir_deg;
char _term[15]; // 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
};