ardupilot/libraries/AP_GPS/GPS_Backend.h

111 lines
3.6 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/>.
*/
/*
GPS driver backend class
*/
#pragma once
#include <GCS_MAVLink/GCS_MAVLink.h>
#include <AP_RTC/JitterCorrection.h>
#include "AP_GPS.h"
class AP_GPS_Backend
{
public:
AP_GPS_Backend(AP_GPS &_gps, AP_GPS::GPS_State &_state, AP_HAL::UARTDriver *_port);
// we declare a virtual destructor so that GPS drivers can
// override with a custom destructor if need be.
virtual ~AP_GPS_Backend(void) {}
// The read() method is the only one needed in each driver. It
// should return true when the backend has successfully received a
// valid packet from the GPS.
virtual bool read() = 0;
// Highest status supported by this GPS.
// Allows external system to identify type of receiver connected.
virtual AP_GPS::GPS_Status highest_supported_status(void) { return AP_GPS::GPS_OK_FIX_3D; }
virtual bool is_configured(void) { return true; }
virtual void inject_data(const uint8_t *data, uint16_t len);
//MAVLink methods
virtual bool supports_mavlink_gps_rtk_message() { return false; }
virtual void send_mavlink_gps_rtk(mavlink_channel_t chan);
virtual void broadcast_configuration_failure_reason(void) const { return ; }
virtual void handle_msg(const mavlink_message_t *msg) { return ; }
// driver specific lag, returns true if the driver is confident in the provided lag
virtual bool get_lag(float &lag) const { lag = 0.2f; return true; }
// driver specific health, returns true if the driver is healthy
virtual bool is_healthy(void) const { return true; }
virtual const char *name() const = 0;
void broadcast_gps_type() const;
virtual void Write_AP_Logger_Log_Startup_messages() const;
virtual bool prepare_for_arming(void) { return true; }
protected:
AP_HAL::UARTDriver *port; ///< UART we are attached to
AP_GPS &gps; ///< access to frontend (for parameters)
AP_GPS::GPS_State &state; ///< public state for this instance
// common utility functions
int32_t swap_int32(int32_t v) const;
int16_t swap_int16(int16_t v) const;
/*
fill in 3D velocity from 2D components
*/
void fill_3d_velocity(void);
/*
fill in time_week_ms and time_week from BCD date and time components
assumes MTK19 millisecond form of bcd_time
*/
void make_gps_time(uint32_t bcd_date, uint32_t bcd_milliseconds);
void _detection_message(char *buffer, uint8_t buflen) const;
bool should_df_log() const;
/*
set a timestamp based on arrival time on uart at current byte,
assuming the message started nbytes ago
*/
void set_uart_timestamp(uint16_t nbytes);
void check_new_itow(uint32_t itow, uint32_t msg_length);
private:
// itow from previous message
uint32_t _last_itow;
uint64_t _pseudo_itow;
uint32_t _last_ms;
uint32_t _rate_ms;
uint32_t _last_rate_ms;
uint16_t _rate_counter;
JitterCorrection jitter_correction;
};