ardupilot/libraries/AP_Compass/AP_Compass_HMC5843.cpp

585 lines
16 KiB
C++

/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
/*
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/>.
*/
/*
* AP_Compass_HMC5843.cpp - Arduino Library for HMC5843 I2C magnetometer
* Code by Jordi Muñoz and Jose Julio. DIYDrones.com
*
* Sensor is conected to I2C port
* Sensor is initialized in Continuos mode (10Hz)
*
*/
// AVR LibC Includes
#include <AP_Math/AP_Math.h>
#include <AP_HAL/AP_HAL.h>
#include "AP_Compass_HMC5843.h"
#include <AP_InertialSensor/AP_InertialSensor.h>
#include <AP_InertialSensor/AuxiliaryBus.h>
extern const AP_HAL::HAL& hal;
#define HMC5843_I2C_ADDR 0x1E
#define ConfigRegA 0x00
#define ConfigRegB 0x01
#define magGain 0x20
#define PositiveBiasConfig 0x11
#define NegativeBiasConfig 0x12
#define NormalOperation 0x10
#define ModeRegister 0x02
#define ContinuousConversion 0x00
#define SingleConversion 0x01
// ConfigRegA valid sample averaging for 5883L
#define SampleAveraging_1 0x00
#define SampleAveraging_2 0x01
#define SampleAveraging_4 0x02
#define SampleAveraging_8 0x03
// ConfigRegA valid data output rates for 5883L
#define DataOutputRate_0_75HZ 0x00
#define DataOutputRate_1_5HZ 0x01
#define DataOutputRate_3HZ 0x02
#define DataOutputRate_7_5HZ 0x03
#define DataOutputRate_15HZ 0x04
#define DataOutputRate_30HZ 0x05
#define DataOutputRate_75HZ 0x06
// constructor
AP_Compass_HMC5843::AP_Compass_HMC5843(Compass &compass, AP_HMC5843_SerialBus *bus) :
AP_Compass_Backend(compass),
_bus(bus),
_retry_time(0),
_mag_x(0),
_mag_y(0),
_mag_z(0),
_mag_x_accum(0),
_mag_y_accum(0),
_mag_z_accum(0),
_accum_count(0),
_last_accum_time(0),
_compass_instance(0),
_product_id(0)
{}
AP_Compass_HMC5843::~AP_Compass_HMC5843()
{
delete _bus;
}
// detect the sensor
AP_Compass_Backend *AP_Compass_HMC5843::detect_i2c(Compass &compass,
AP_HAL::I2CDriver *i2c)
{
AP_HMC5843_SerialBus *bus = new AP_HMC5843_SerialBus_I2C(i2c, HMC5843_I2C_ADDR);
if (!bus)
return nullptr;
return _detect(compass, bus);
}
AP_Compass_Backend *AP_Compass_HMC5843::detect_mpu6000(Compass &compass)
{
AP_InertialSensor &ins = *AP_InertialSensor::get_instance();
AP_HMC5843_SerialBus *bus = new AP_HMC5843_SerialBus_MPU6000(ins, HMC5843_I2C_ADDR);
if (!bus)
return nullptr;
return _detect(compass, bus);
}
AP_Compass_Backend *AP_Compass_HMC5843::_detect(Compass &compass,
AP_HMC5843_SerialBus *bus)
{
AP_Compass_HMC5843 *sensor = new AP_Compass_HMC5843(compass, bus);
if (!sensor) {
delete bus;
return nullptr;
}
if (!sensor->init()) {
delete sensor;
return nullptr;
}
return sensor;
}
// read_register - read a register value
bool AP_Compass_HMC5843::read_register(uint8_t address, uint8_t *value)
{
if (_bus->register_read(address, value) != 0) {
_retry_time = hal.scheduler->millis() + 1000;
return false;
}
return true;
}
// write_register - update a register value
bool AP_Compass_HMC5843::write_register(uint8_t address, uint8_t value)
{
if (_bus->register_write(address, value) != 0) {
_retry_time = hal.scheduler->millis() + 1000;
return false;
}
return true;
}
// Read Sensor data
bool AP_Compass_HMC5843::read_raw()
{
struct AP_HMC5843_SerialBus::raw_value rv;
if (_bus->read_raw(&rv) != 0) {
_bus->set_high_speed(false);
_retry_time = hal.scheduler->millis() + 1000;
return false;
}
int16_t rx, ry, rz;
rx = (((int16_t)rv.val[0]) << 8) | rv.val[1];
if (_product_id == AP_COMPASS_TYPE_HMC5883L) {
rz = (((int16_t)rv.val[2]) << 8) | rv.val[3];
ry = (((int16_t)rv.val[4]) << 8) | rv.val[5];
} else {
ry = (((int16_t)rv.val[2]) << 8) | rv.val[3];
rz = (((int16_t)rv.val[4]) << 8) | rv.val[5];
}
if (rx == -4096 || ry == -4096 || rz == -4096) {
// no valid data available
return false;
}
_mag_x = -rx;
_mag_y = ry;
_mag_z = -rz;
return true;
}
// accumulate a reading from the magnetometer
void AP_Compass_HMC5843::accumulate(void)
{
if (!_initialised) {
// someone has tried to enable a compass for the first time
// mid-flight .... we can't do that yet (especially as we won't
// have the right orientation!)
return;
}
uint32_t tnow = hal.scheduler->micros();
if (_accum_count != 0 && (tnow - _last_accum_time) < 13333) {
// the compass gets new data at 75Hz
return;
}
if (!_bus_sem->take(1)) {
// the bus is busy - try again later
return;
}
bool result = read_raw();
_bus_sem->give();
if (result) {
// the _mag_N values are in the range -2048 to 2047, so we can
// accumulate up to 15 of them in an int16_t. Let's make it 14
// for ease of calculation. We expect to do reads at 10Hz, and
// we get new data at most 75Hz, so we don't expect to
// accumulate more than 8 before a read
// get raw_field - sensor frame, uncorrected
Vector3f raw_field = Vector3f(_mag_x, _mag_y, _mag_z);
// rotate raw_field from sensor frame to body frame
rotate_field(raw_field, _compass_instance);
// publish raw_field (uncorrected point sample) for calibration use
publish_raw_field(raw_field, tnow, _compass_instance);
// correct raw_field for known errors
correct_field(raw_field, _compass_instance);
// publish raw_field (corrected point sample) for EKF use
publish_unfiltered_field(raw_field, tnow, _compass_instance);
_mag_x_accum += raw_field.x;
_mag_y_accum += raw_field.y;
_mag_z_accum += raw_field.z;
_accum_count++;
if (_accum_count == 14) {
_mag_x_accum /= 2;
_mag_y_accum /= 2;
_mag_z_accum /= 2;
_accum_count = 7;
}
_last_accum_time = tnow;
}
}
/*
* re-initialise after a IO error
*/
bool AP_Compass_HMC5843::re_initialise()
{
if (!write_register(ConfigRegA, _base_config) ||
!write_register(ConfigRegB, magGain) ||
!write_register(ModeRegister, ContinuousConversion))
return false;
return true;
}
bool AP_Compass_HMC5843::_detect_version()
{
_base_config = 0x0;
if (!write_register(ConfigRegA, SampleAveraging_8<<5 | DataOutputRate_75HZ<<2 | NormalOperation) ||
!read_register(ConfigRegA, &_base_config)) {
return false;
}
if (_base_config == (SampleAveraging_8<<5 | DataOutputRate_75HZ<<2 | NormalOperation)) {
/* a 5883L supports the sample averaging config */
_product_id = AP_COMPASS_TYPE_HMC5883L;
return true;
} else if (_base_config == (NormalOperation | DataOutputRate_75HZ<<2)) {
_product_id = AP_COMPASS_TYPE_HMC5843;
return true;
} else {
/* not behaving like either supported compass type */
return false;
}
}
// Public Methods //////////////////////////////////////////////////////////////
bool
AP_Compass_HMC5843::init()
{
uint8_t calibration_gain = 0x20;
uint16_t expected_x = 715;
uint16_t expected_yz = 715;
_gain_multiple = 1.0;
_bus_sem = _bus->get_semaphore();
hal.scheduler->suspend_timer_procs();
if (!_bus_sem || !_bus_sem->take(HAL_SEMAPHORE_BLOCK_FOREVER)) {
hal.console->printf_P(PSTR("HMC5843: Unable to get bus semaphore\n"));
goto fail_sem;
}
if (!_bus->configure()) {
hal.console->printf_P(PSTR("HMC5843: Could not configure the bus\n"));
goto errout;
}
if (!_detect_version()) {
hal.console->printf_P(PSTR("HMC5843: Could not detect version\n"));
goto errout;
}
if (_product_id == AP_COMPASS_TYPE_HMC5883L) {
calibration_gain = 0x60;
/*
note that the HMC5883 datasheet gives the x and y expected
values as 766 and the z as 713. Experiments have shown the x
axis is around 766, and the y and z closer to 713.
*/
expected_x = 766;
expected_yz = 713;
_gain_multiple = 660.0f / 1090; // adjustment for runtime vs calibration gain
}
if (!_calibrate(calibration_gain, expected_x, expected_yz)) {
hal.console->printf_P(PSTR("HMC5843: Could not calibrate sensor\n"));
goto errout;
}
// leave test mode
if (!re_initialise()) {
goto errout;
}
if (!_bus->start_measurements()) {
hal.console->printf_P(PSTR("HMC5843: Could not start measurements on bus\n"));
goto errout;
}
_initialised = true;
_bus_sem->give();
hal.scheduler->resume_timer_procs();
// perform an initial read
read();
#if 0
hal.console->printf_P(PSTR("CalX: %.2f CalY: %.2f CalZ: %.2f\n"),
_scaling[0], _scaling[1], _scaling[2]);
#endif
_compass_instance = register_compass();
set_dev_id(_compass_instance, _product_id);
set_milligauss_ratio(_compass_instance, 1.0f / _gain_multiple);
#if CONFIG_HAL_BOARD == HAL_BOARD_LINUX && CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_RASPILOT
set_external(_compass_instance, true);
#endif
return true;
errout:
_bus_sem->give();
fail_sem:
hal.scheduler->resume_timer_procs();
return false;
}
bool AP_Compass_HMC5843::_calibrate(uint8_t calibration_gain,
uint16_t expected_x,
uint16_t expected_yz)
{
int numAttempts = 0, good_count = 0;
bool success = false;
while (success == 0 && numAttempts < 25 && good_count < 5)
{
numAttempts++;
// force positiveBias (compass should return 715 for all channels)
if (!write_register(ConfigRegA, PositiveBiasConfig))
continue; // compass not responding on the bus
hal.scheduler->delay(50);
// set gains
if (!write_register(ConfigRegB, calibration_gain) ||
!write_register(ModeRegister, SingleConversion))
continue;
// read values from the compass
hal.scheduler->delay(50);
if (!read_raw())
continue; // we didn't read valid values
hal.scheduler->delay(10);
float cal[3];
// hal.console->printf_P(PSTR("mag %d %d %d\n"), _mag_x, _mag_y, _mag_z);
cal[0] = fabsf(expected_x / (float)_mag_x);
cal[1] = fabsf(expected_yz / (float)_mag_y);
cal[2] = fabsf(expected_yz / (float)_mag_z);
// hal.console->printf_P(PSTR("cal=%.2f %.2f %.2f\n"), cal[0], cal[1], cal[2]);
// we throw away the first two samples as the compass may
// still be changing its state from the application of the
// strap excitation. After that we accept values in a
// reasonable range
if (numAttempts <= 2) {
continue;
}
#define IS_CALIBRATION_VALUE_VALID(val) (val > 0.7f && val < 1.35f)
if (IS_CALIBRATION_VALUE_VALID(cal[0]) &&
IS_CALIBRATION_VALUE_VALID(cal[1]) &&
IS_CALIBRATION_VALUE_VALID(cal[2])) {
// hal.console->printf_P(PSTR("car=%.2f %.2f %.2f good\n"), cal[0], cal[1], cal[2]);
good_count++;
_scaling[0] += cal[0];
_scaling[1] += cal[1];
_scaling[2] += cal[2];
}
#undef IS_CALIBRATION_VALUE_VALID
#if 0
/* useful for debugging */
hal.console->printf_P(PSTR("MagX: %d MagY: %d MagZ: %d\n"), (int)_mag_x, (int)_mag_y, (int)_mag_z);
hal.console->printf_P(PSTR("CalX: %.2f CalY: %.2f CalZ: %.2f\n"), cal[0], cal[1], cal[2]);
#endif
}
if (good_count >= 5) {
/*
The use of _gain_multiple below is incorrect, as the gain
difference between 2.5Ga mode and 1Ga mode is already taken
into account by the expected_x and expected_yz values. We
are not going to fix it however as it would mean all
APM1/APM2 users redoing their compass calibration. The
impact is that the values we report on APM1/APM2 are lower
than they should be (by a multiple of about 0.6). This
doesn't have any impact other than the learned compass
offsets
*/
_scaling[0] = _scaling[0] * _gain_multiple / good_count;
_scaling[1] = _scaling[1] * _gain_multiple / good_count;
_scaling[2] = _scaling[2] * _gain_multiple / good_count;
success = true;
} else {
/* best guess */
_scaling[0] = 1.0;
_scaling[1] = 1.0;
_scaling[2] = 1.0;
}
return success;
}
// Read Sensor data
void AP_Compass_HMC5843::read()
{
if (!_initialised) {
// someone has tried to enable a compass for the first time
// mid-flight .... we can't do that yet (especially as we won't
// have the right orientation!)
return;
}
if (_retry_time != 0) {
if (hal.scheduler->millis() < _retry_time) {
return;
}
if (!re_initialise()) {
_retry_time = hal.scheduler->millis() + 1000;
_bus->set_high_speed(false);
return;
}
}
if (_accum_count == 0) {
accumulate();
if (_retry_time != 0) {
_bus->set_high_speed(false);
return;
}
}
Vector3f field(_mag_x_accum * _scaling[0],
_mag_y_accum * _scaling[1],
_mag_z_accum * _scaling[2]);
field /= _accum_count;
_accum_count = 0;
_mag_x_accum = _mag_y_accum = _mag_z_accum = 0;
// rotate to the desired orientation
if (_product_id == AP_COMPASS_TYPE_HMC5883L) {
field.rotate(ROTATION_YAW_90);
}
publish_filtered_field(field, _compass_instance);
_retry_time = 0;
}
/* I2C implementation of the HMC5843 */
AP_HMC5843_SerialBus_I2C::AP_HMC5843_SerialBus_I2C(AP_HAL::I2CDriver *i2c, uint8_t addr)
: _i2c(i2c)
, _addr(addr)
{
}
void AP_HMC5843_SerialBus_I2C::set_high_speed(bool val)
{
_i2c->setHighSpeed(val);
}
uint8_t AP_HMC5843_SerialBus_I2C::register_read(uint8_t reg, uint8_t *buf, uint8_t size)
{
return _i2c->readRegisters(_addr, reg, size, buf);
}
uint8_t AP_HMC5843_SerialBus_I2C::register_write(uint8_t reg, uint8_t val)
{
return _i2c->writeRegister(_addr, reg, val);
}
AP_HAL::Semaphore* AP_HMC5843_SerialBus_I2C::get_semaphore()
{
return _i2c->get_semaphore();
}
uint8_t AP_HMC5843_SerialBus_I2C::read_raw(struct raw_value *rv)
{
return register_read(0x03, (uint8_t*)rv, sizeof(*rv));
}
/* MPU6000 implementation of the HMC5843 */
AP_HMC5843_SerialBus_MPU6000::AP_HMC5843_SerialBus_MPU6000(AP_InertialSensor &ins,
uint8_t addr)
{
// Only initialize members. Fails are handled by configure or while
// getting the semaphore
_bus = ins.get_auxiliar_bus(HAL_INS_MPU60XX_SPI);
if (!_bus)
return;
_slave = _bus->request_next_slave(addr);
}
AP_HMC5843_SerialBus_MPU6000::~AP_HMC5843_SerialBus_MPU6000()
{
/* After started it's owned by AuxiliaryBus */
if (!_started)
delete _slave;
}
bool AP_HMC5843_SerialBus_MPU6000::configure()
{
if (!_bus || !_slave)
return false;
return true;
}
void AP_HMC5843_SerialBus_MPU6000::set_high_speed(bool val)
{
}
uint8_t AP_HMC5843_SerialBus_MPU6000::register_read(uint8_t reg, uint8_t *buf, uint8_t size)
{
return _slave->passthrough_read(reg, buf, size) == size ? 0 : 1;
}
uint8_t AP_HMC5843_SerialBus_MPU6000::register_write(uint8_t reg, uint8_t val)
{
return _slave->passthrough_write(reg, val) >= 0 ? 0 : 1;
}
AP_HAL::Semaphore* AP_HMC5843_SerialBus_MPU6000::get_semaphore()
{
return _bus ? _bus->get_semaphore() : nullptr;
}
uint8_t AP_HMC5843_SerialBus_MPU6000::read_raw(struct raw_value *rv)
{
if (_started)
return _slave->read((uint8_t*)rv) >= 0 ? 0 : 1;
return _slave->passthrough_read(0x03, (uint8_t*)rv, sizeof(*rv)) >= 0 ? 0 : 1;
}
bool AP_HMC5843_SerialBus_MPU6000::start_measurements()
{
if (_bus->register_periodic_read(_slave, 0x03, sizeof(struct raw_value)) < 0)
return false;
_started = true;
return true;
}