ardupilot/libraries/AP_Compass/AP_Compass_Backend.h

83 lines
2.7 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/>.
*/
/*
Compass driver backend class. Each supported compass sensor type
needs to have an object derived from this class.
*/
#pragma once
#include "AP_Compass.h"
class Compass; // forward declaration
class AP_Compass_Backend
{
public:
AP_Compass_Backend(Compass &compass);
// we declare a virtual destructor so that drivers can
// override with a custom destructor if need be.
virtual ~AP_Compass_Backend(void) {}
// initialize the magnetometers
virtual bool init(void) = 0;
// read sensor data
virtual void read(void) = 0;
// accumulate a reading from the magnetometer. Optional in
// backends
virtual void accumulate(void) {};
protected:
/*
* A compass measurement is expected to pass through the following functions:
* 1. rotate_field - this rotates the measurement in-place from sensor frame
* to body frame
* 2. publish_raw_field - this provides an uncorrected point-sample for
* calibration libraries
* 3. correct_field - this corrects the measurement in-place for hard iron,
* soft iron, motor interference, and non-orthagonality errors
* 4. publish_filtered_field - legacy filtered magnetic field
*
* All those functions expect the mag field to be in milligauss.
*/
void rotate_field(Vector3f &mag, uint8_t instance);
void publish_raw_field(const Vector3f &mag, uint32_t time_us, uint8_t instance);
void correct_field(Vector3f &mag, uint8_t i);
void publish_filtered_field(const Vector3f &mag, uint8_t instance);
void set_last_update_usec(uint32_t last_update, uint8_t instance);
// register a new compass instance with the frontend
uint8_t register_compass(void) const;
// set dev_id for an instance
void set_dev_id(uint8_t instance, uint32_t dev_id);
// set external state for an instance
void set_external(uint8_t instance, bool external);
// tell if instance is an external compass
bool is_external(uint8_t instance);
// access to frontend
Compass &_compass;
private:
void apply_corrections(Vector3f &mag, uint8_t i);
};