Example #1
0
void
BMI160::measure()
{
	if (hrt_absolute_time() < _reset_wait) {
		// we're waiting for a reset to complete
		return;
	}

	struct BMIReport bmi_report;

	struct Report {
		int16_t		accel_x;
		int16_t		accel_y;
		int16_t		accel_z;
		int16_t		temp;
		int16_t		gyro_x;
		int16_t		gyro_y;
		int16_t		gyro_z;
	} report;

	/* start measuring */
	perf_begin(_sample_perf);

	/*
	 * Fetch the full set of measurements from the BMI160 in one pass.
	 */
	bmi_report.cmd = BMIREG_GYR_X_L | DIR_READ;

	set_frequency(BMI160_LOW_BUS_SPEED);

	uint8_t		status = read_reg(BMIREG_STATUS, BMI160_LOW_BUS_SPEED);

	if (OK != transfer((uint8_t *)&bmi_report, ((uint8_t *)&bmi_report), sizeof(bmi_report))) {
		return;
	}

	check_registers();

	if ((!(status && (0x80)))  && (!(status && (0x04)))) {
		perf_end(_sample_perf);
		perf_count(_duplicates);
		_got_duplicate = true;
		return;
	}

	_last_accel[0] = bmi_report.accel_x;
	_last_accel[1] = bmi_report.accel_y;
	_last_accel[2] = bmi_report.accel_z;
	_got_duplicate = false;

	uint8_t temp_l = read_reg(BMIREG_TEMP_0, BMI160_LOW_BUS_SPEED);
	uint8_t temp_h = read_reg(BMIREG_TEMP_1, BMI160_LOW_BUS_SPEED);

	report.temp = ((temp_h << 8) + temp_l);

	report.accel_x = bmi_report.accel_x;
	report.accel_y = bmi_report.accel_y;
	report.accel_z = bmi_report.accel_z;

	report.gyro_x = bmi_report.gyro_x;
	report.gyro_y = bmi_report.gyro_y;
	report.gyro_z = bmi_report.gyro_z;

	if (report.accel_x == 0 &&
	    report.accel_y == 0 &&
	    report.accel_z == 0 &&
	    report.temp == 0 &&
	    report.gyro_x == 0 &&
	    report.gyro_y == 0 &&
	    report.gyro_z == 0) {
		// all zero data - probably a SPI bus error
		perf_count(_bad_transfers);
		perf_end(_sample_perf);
		// note that we don't call reset() here as a reset()
		// costs 20ms with interrupts disabled. That means if
		// the bmi160 does go bad it would cause a FMU failure,
		// regardless of whether another sensor is available,
		return;
	}

	perf_count(_good_transfers);

	if (_register_wait != 0) {
		// we are waiting for some good transfers before using
		// the sensor again. We still increment
		// _good_transfers, but don't return any data yet
		_register_wait--;
		return;
	}

	/*
	 * Report buffers.
	 */
	accel_report		arb;
	gyro_report		grb;

	/*
	 * Adjust and scale results to m/s^2.
	 */
	grb.timestamp = arb.timestamp = hrt_absolute_time();

	// report the error count as the sum of the number of bad
	// transfers and bad register reads. This allows the higher
	// level code to decide if it should use this sensor based on
	// whether it has had failures
	grb.error_count = arb.error_count = perf_event_count(_bad_transfers) + perf_event_count(_bad_registers);

	/*
	 * 1) Scale raw value to SI units using scaling from datasheet.
	 * 2) Subtract static offset (in SI units)
	 * 3) Scale the statically calibrated values with a linear
	 *    dynamically obtained factor
	 *
	 * Note: the static sensor offset is the number the sensor outputs
	 * 	 at a nominally 'zero' input. Therefore the offset has to
	 * 	 be subtracted.
	 *
	 *	 Example: A gyro outputs a value of 74 at zero angular rate
	 *	 	  the offset is 74 from the origin and subtracting
	 *		  74 from all measurements centers them around zero.
	 */


	/* NOTE: Axes have been swapped to match the board a few lines above. */

	arb.x_raw = report.accel_x;
	arb.y_raw = report.accel_y;
	arb.z_raw = report.accel_z;

	float xraw_f = report.accel_x;
	float yraw_f = report.accel_y;
	float zraw_f = report.accel_z;

	// apply user specified rotation
	rotate_3f(_rotation, xraw_f, yraw_f, zraw_f);

	float x_in_new = ((xraw_f * _accel_range_scale) - _accel_scale.x_offset) * _accel_scale.x_scale;
	float y_in_new = ((yraw_f * _accel_range_scale) - _accel_scale.y_offset) * _accel_scale.y_scale;
	float z_in_new = ((zraw_f * _accel_range_scale) - _accel_scale.z_offset) * _accel_scale.z_scale;

	arb.x = _accel_filter_x.apply(x_in_new);
	arb.y = _accel_filter_y.apply(y_in_new);
	arb.z = _accel_filter_z.apply(z_in_new);

	math::Vector<3> aval(x_in_new, y_in_new, z_in_new);
	math::Vector<3> aval_integrated;

	bool accel_notify = _accel_int.put(arb.timestamp, aval, aval_integrated, arb.integral_dt);
	arb.x_integral = aval_integrated(0);
	arb.y_integral = aval_integrated(1);
	arb.z_integral = aval_integrated(2);

	arb.scaling = _accel_range_scale;
	arb.range_m_s2 = _accel_range_m_s2;

	_last_temperature = 23 + report.temp * 1.0f / 512.0f;

	arb.temperature_raw = report.temp;
	arb.temperature = _last_temperature;

	grb.x_raw = report.gyro_x;
	grb.y_raw = report.gyro_y;
	grb.z_raw = report.gyro_z;

	xraw_f = report.gyro_x;
	yraw_f = report.gyro_y;
	zraw_f = report.gyro_z;

	// apply user specified rotation
	rotate_3f(_rotation, xraw_f, yraw_f, zraw_f);

	float x_gyro_in_new = ((xraw_f * _gyro_range_scale) - _gyro_scale.x_offset) * _gyro_scale.x_scale;
	float y_gyro_in_new = ((yraw_f * _gyro_range_scale) - _gyro_scale.y_offset) * _gyro_scale.y_scale;
	float z_gyro_in_new = ((zraw_f * _gyro_range_scale) - _gyro_scale.z_offset) * _gyro_scale.z_scale;

	grb.x = _gyro_filter_x.apply(x_gyro_in_new);
	grb.y = _gyro_filter_y.apply(y_gyro_in_new);
	grb.z = _gyro_filter_z.apply(z_gyro_in_new);

	math::Vector<3> gval(x_gyro_in_new, y_gyro_in_new, z_gyro_in_new);
	math::Vector<3> gval_integrated;

	bool gyro_notify = _gyro_int.put(arb.timestamp, gval, gval_integrated, grb.integral_dt);
	grb.x_integral = gval_integrated(0);
	grb.y_integral = gval_integrated(1);
	grb.z_integral = gval_integrated(2);

	grb.scaling = _gyro_range_scale;
	grb.range_rad_s = _gyro_range_rad_s;

	grb.temperature_raw = report.temp;
	grb.temperature = _last_temperature;

	_accel_reports->force(&arb);
	_gyro_reports->force(&grb);

	/* notify anyone waiting for data */
	if (accel_notify) {
		poll_notify(POLLIN);
	}

	if (gyro_notify) {
		_gyro->parent_poll_notify();
	}

	if (accel_notify && !(_pub_blocked)) {
		/* log the time of this report */
		perf_begin(_controller_latency_perf);
		/* publish it */
		orb_publish(ORB_ID(sensor_accel), _accel_topic, &arb);
	}

	if (gyro_notify && !(_pub_blocked)) {
		/* publish it */
		orb_publish(ORB_ID(sensor_gyro), _gyro->_gyro_topic, &grb);
	}

	/* stop measuring */
	perf_end(_sample_perf);
}
Example #2
0
int
SF0X::collect()
{
	int	ret;

	perf_begin(_sample_perf);

	/* clear buffer if last read was too long ago */
	int64_t read_elapsed = hrt_elapsed_time(&_last_read);

	/* the buffer for read chars is buflen minus null termination */
	char readbuf[sizeof(_linebuf)];
	unsigned readlen = sizeof(readbuf) - 1;

	/* read from the sensor (uart buffer) */
	ret = ::read(_fd, &readbuf[0], readlen);

	if (ret < 0) {
		PX4_DEBUG("read err: %d", ret);
		perf_count(_comms_errors);
		perf_end(_sample_perf);

		/* only throw an error if we time out */
		if (read_elapsed > (_conversion_interval * 2)) {
			return ret;

		} else {
			return -EAGAIN;
		}

	} else if (ret == 0) {
		return -EAGAIN;
	}

	_last_read = hrt_absolute_time();

	float distance_m = -1.0f;
	bool valid = false;

	for (int i = 0; i < ret; i++) {
		if (OK == sf0x_parser(readbuf[i], _linebuf, &_linebuf_index, &_parse_state, &distance_m)) {
			valid = true;
		}
	}

	if (!valid) {
		return -EAGAIN;
	}

	PX4_DEBUG("val (float): %8.4f, raw: %s, valid: %s", (double)distance_m, _linebuf, ((valid) ? "OK" : "NO"));

	struct distance_sensor_s report;

	report.timestamp = hrt_absolute_time();
	report.type = distance_sensor_s::MAV_DISTANCE_SENSOR_LASER;
	report.orientation = _rotation;
	report.current_distance = distance_m;
	report.min_distance = get_minimum_distance();
	report.max_distance = get_maximum_distance();
	report.variance = 0.0f;
	report.signal_quality = -1;
	/* TODO: set proper ID */
	report.id = 0;

	/* publish it */
	orb_publish(ORB_ID(distance_sensor), _distance_sensor_topic, &report);

	_reports->force(&report);

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	ret = OK;

	perf_end(_sample_perf);
	return ret;
}
Example #3
0
int
MB12XX::collect()
{
	int	ret = -EIO;

	/* read from the sensor */
	uint8_t val[2] = {0, 0};

	perf_begin(_sample_perf);

	ret = transfer(nullptr, 0, &val[0], 2);

	if (ret < 0) {
		debug("error reading from sensor: %d", ret);
		perf_count(_comms_errors);
		perf_end(_sample_perf);
		return ret;
	}

	uint16_t distance = val[0] << 8 | val[1];
	float si_units = (distance * 1.0f) / 100.0f; /* cm to m */
	struct range_finder_report report;

	/* this should be fairly close to the end of the measurement, so the best approximation of the time */
	report.timestamp = hrt_absolute_time();
	report.error_count = perf_event_count(_comms_errors);

	/* if only one sonar, write it to the original distance parameter so that it's still used as altitude sonar */
	if (addr_ind.size() == 1) {
		report.distance = si_units;

		for (unsigned i = 0; i < (MB12XX_MAX_RANGEFINDERS); i++) {
			report.distance_vector[i] = 0;
		}

		report.just_updated = 0;

	} else {
		/* for multiple sonars connected */

		/* don't use the orginial single sonar variable */
		report.distance = 0;

		/* intermediate vector _latest_sonar_measurements is used to store the measurements as every cycle the other sonar values 			of the report are thrown away and/or filled in with garbage. We don't want this. We want the report to give the latest 			value for each connected sonar */
		_latest_sonar_measurements[_cycle_counter] = si_units;

		for (unsigned i = 0; i < (_latest_sonar_measurements.size()); i++) {
			report.distance_vector[i] = _latest_sonar_measurements[i];
		}

		/* a just_updated variable is added to indicate to autopilot (ardupilot or whatever) which sonar has most recently been 		collected as this could be of use for Kalman filters */
		report.just_updated = _index_counter;

		/* Make sure all elements of the distance vector for which no sonar is connected are zero to prevent strange numbers */
		for (unsigned i = 0; i < (MB12XX_MAX_RANGEFINDERS - addr_ind.size()); i++) {
			report.distance_vector[addr_ind.size() + i] = 0;
		}
	}

	report.minimum_distance = get_minimum_distance();
	report.maximum_distance = get_maximum_distance();
	report.valid = si_units > get_minimum_distance() && si_units < get_maximum_distance() ? 1 : 0;

	/* publish it, if we are the primary */
	if (_range_finder_topic >= 0) {
		orb_publish(ORB_ID(sensor_range_finder), _range_finder_topic, &report);
	}

	if (_reports->force(&report)) {
		perf_count(_buffer_overflows);
	}

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	ret = OK;

	perf_end(_sample_perf);
	return ret;
}
Example #4
0
void
L3GD20::measure()
{
	/* status register and data as read back from the device */
#pragma pack(push, 1)
	struct {
		uint8_t		cmd;
		int8_t		temp;
		uint8_t		status;
		int16_t		x;
		int16_t		y;
		int16_t		z;
	} raw_report;
#pragma pack(pop)

	gyro_report report;

	/* start the performance counter */
	perf_begin(_sample_perf);

        check_registers();

	/* fetch data from the sensor */
	memset(&raw_report, 0, sizeof(raw_report));
	raw_report.cmd = ADDR_OUT_TEMP | DIR_READ | ADDR_INCREMENT;
	transfer((uint8_t *)&raw_report, (uint8_t *)&raw_report, sizeof(raw_report));

        if (!(raw_report.status & STATUS_ZYXDA)) {
		perf_end(_sample_perf);
		perf_count(_duplicates);
		return;
        }

	/*
	 * 1) Scale raw value to SI units using scaling from datasheet.
	 * 2) Subtract static offset (in SI units)
	 * 3) Scale the statically calibrated values with a linear
	 *    dynamically obtained factor
	 *
	 * Note: the static sensor offset is the number the sensor outputs
	 * 	 at a nominally 'zero' input. Therefore the offset has to
	 * 	 be subtracted.
	 *
	 *	 Example: A gyro outputs a value of 74 at zero angular rate
	 *	 	  the offset is 74 from the origin and subtracting
	 *		  74 from all measurements centers them around zero.
	 */
	report.timestamp = hrt_absolute_time();
        report.error_count = perf_event_count(_bad_registers);

	switch (_orientation) {

		case SENSOR_BOARD_ROTATION_000_DEG:
			/* keep axes in place */
			report.x_raw = raw_report.x;
			report.y_raw = raw_report.y;
			break;

		case SENSOR_BOARD_ROTATION_090_DEG:
			/* swap x and y */
			report.x_raw = raw_report.y;
			report.y_raw = raw_report.x;
			break;

		case SENSOR_BOARD_ROTATION_180_DEG:
			/* swap x and y and negate both */
			report.x_raw = ((raw_report.x == -32768) ? 32767 : -raw_report.x);
			report.y_raw = ((raw_report.y == -32768) ? 32767 : -raw_report.y);
			break;

		case SENSOR_BOARD_ROTATION_270_DEG:
			/* swap x and y and negate y */
			report.x_raw = raw_report.y;
			report.y_raw = ((raw_report.x == -32768) ? 32767 : -raw_report.x);
			break;
	}

	report.z_raw = raw_report.z;

	report.temperature_raw = raw_report.temp;

	float xraw_f = report.x_raw;
	float yraw_f = report.y_raw;
	float zraw_f = report.z_raw;

	// apply user specified rotation
	rotate_3f(_rotation, xraw_f, yraw_f, zraw_f);

	report.x = ((xraw_f * _gyro_range_scale) - _gyro_scale.x_offset) * _gyro_scale.x_scale;
	report.y = ((yraw_f * _gyro_range_scale) - _gyro_scale.y_offset) * _gyro_scale.y_scale;
	report.z = ((zraw_f * _gyro_range_scale) - _gyro_scale.z_offset) * _gyro_scale.z_scale;

	report.x = _gyro_filter_x.apply(report.x);
	report.y = _gyro_filter_y.apply(report.y);
	report.z = _gyro_filter_z.apply(report.z);

	report.temperature = L3GD20_TEMP_OFFSET_CELSIUS - raw_report.temp;

	report.scaling = _gyro_range_scale;
	report.range_rad_s = _gyro_range_rad_s;

	_reports->force(&report);

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	/* publish for subscribers */
	if (!(_pub_blocked)) {
		/* publish it */
		orb_publish(ORB_ID(sensor_gyro), _gyro_topic, &report);
	}

	_read++;

	/* stop the perf counter */
	perf_end(_sample_perf);
}
Example #5
0
int
MEASAirspeed::collect()
{
	int	ret = -EIO;

	/* read from the sensor */
	uint8_t val[4] = {0, 0, 0, 0};


	perf_begin(_sample_perf);

	ret = transfer(nullptr, 0, &val[0], 4);

	if (ret < 0) {
		perf_count(_comms_errors);
		perf_end(_sample_perf);
		return ret;
	}

	uint8_t status = (val[0] & 0xC0) >> 6;

	switch (status) {
	case 0:
		break;

	case 1:
		/* fallthrough */
	case 2:
		/* fallthrough */
	case 3:
		perf_count(_comms_errors);
		perf_end(_sample_perf);
		return -EAGAIN;
	}

	int16_t dp_raw = 0, dT_raw = 0;
	dp_raw = (val[0] << 8) + val[1];
	/* mask the used bits */
	dp_raw = 0x3FFF & dp_raw;
	dT_raw = (val[2] << 8) + val[3];
	dT_raw = (0xFFE0 & dT_raw) >> 5;
	float temperature = ((200.0f * dT_raw) / 2047) - 50;

	// Calculate differential pressure. As its centered around 8000
	// and can go positive or negative
	const float P_min = -1.0f;
	const float P_max = 1.0f;
	const float PSI_to_Pa = 6894.757f;
	/*
	  this equation is an inversion of the equation in the
	  pressure transfer function figure on page 4 of the datasheet

	  We negate the result so that positive differential pressures
	  are generated when the bottom port is used as the static
	  port on the pitot and top port is used as the dynamic port
	 */
	float diff_press_PSI = -((dp_raw - 0.1f*16383) * (P_max-P_min)/(0.8f*16383) + P_min);
	float diff_press_pa_raw = diff_press_PSI * PSI_to_Pa;

        // correct for 5V rail voltage if possible
        voltage_correction(diff_press_pa_raw, temperature);

	float diff_press_pa = fabsf(diff_press_pa_raw - _diff_pres_offset);
	
	/*
	  note that we return both the absolute value with offset
	  applied and a raw value without the offset applied. This
	  makes it possible for higher level code to detect if the
	  user has the tubes connected backwards, and also makes it
	  possible to correctly use offsets calculated by a higher
	  level airspeed driver.

	  With the above calculation the MS4525 sensor will produce a
	  positive number when the top port is used as a dynamic port
	  and bottom port is used as the static port

	  Also note that the _diff_pres_offset is applied before the
	  fabsf() not afterwards. It needs to be done this way to
	  prevent a bias at low speeds, but this also means that when
	  setting a offset you must set it based on the raw value, not
	  the offset value
	 */
	
	struct differential_pressure_s report;

	/* track maximum differential pressure measured (so we can work out top speed). */
	if (diff_press_pa > _max_differential_pressure_pa) {
		_max_differential_pressure_pa = diff_press_pa;
	}

	report.timestamp = hrt_absolute_time();
	report.error_count = perf_event_count(_comms_errors);
	report.temperature = temperature;
	report.differential_pressure_pa = diff_press_pa;
	report.differential_pressure_raw_pa = diff_press_pa_raw;
	report.voltage = 0;
	report.max_differential_pressure_pa = _max_differential_pressure_pa;

	if (_airspeed_pub > 0 && !(_pub_blocked)) {
		/* publish it */
		orb_publish(ORB_ID(differential_pressure), _airspeed_pub, &report);
	}

	new_report(report);

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	ret = OK;

	perf_end(_sample_perf);

	return ret;
}
void
LSM303D_mag::parent_poll_notify()
{
    poll_notify(POLLIN);
}
Example #7
0
void
BATT_SMBUS::cycle()
{
	// get current time
	uint64_t now = hrt_absolute_time();

	// exit without rescheduling if we have failed to find a battery after 10 seconds
	if (!_enabled && (now - _start_time > BATT_SMBUS_TIMEOUT_MS)) {
		warnx("did not find smart battery");
		return;
	}

	// read data from sensor
	struct battery_status_s new_report;

	// set time of reading
	new_report.timestamp = now;

	// read voltage
	uint16_t tmp;

	if (read_reg(BATT_SMBUS_VOLTAGE, tmp) == OK) {
		// initialise new_report
		memset(&new_report, 0, sizeof(new_report));

		// convert millivolts to volts
		new_report.voltage_v = ((float)tmp) / 1000.0f;

		// read current
		uint8_t buff[4];

		if (read_block(BATT_SMBUS_CURRENT, buff, 4, false) == 4) {
			new_report.current_a = -(float)((int32_t)((uint32_t)buff[3] << 24 | (uint32_t)buff[2] << 16 | (uint32_t)buff[1] << 8 |
							(uint32_t)buff[0])) / 1000.0f;
		}

		// read battery design capacity
		if (_batt_capacity == 0) {
			if (read_reg(BATT_SMBUS_FULL_CHARGE_CAPACITY, tmp) == OK) {
				_batt_capacity = tmp;
			}
		}

		// read remaining capacity
		if (_batt_capacity > 0) {
			if (read_reg(BATT_SMBUS_REMAINING_CAPACITY, tmp) == OK) {
				if (tmp < _batt_capacity) {
					new_report.discharged_mah = _batt_capacity - tmp;
				}
			}
		}

		// publish to orb
		if (_batt_topic != nullptr) {
			orb_publish(_batt_orb_id, _batt_topic, &new_report);

		} else {
			_batt_topic = orb_advertise(_batt_orb_id, &new_report);

			if (_batt_topic == nullptr) {
				errx(1, "ADVERT FAIL");
			}
		}

		// copy report for test()
		_last_report = new_report;

		// post a report to the ring
		_reports->force(&new_report);

		// notify anyone waiting for data
		poll_notify(POLLIN);

		// record we are working
		_enabled = true;
	}

	// schedule a fresh cycle call when the measurement is done
	work_queue(HPWORK, &_work, (worker_t)&BATT_SMBUS::cycle_trampoline, this,
		   USEC2TICK(BATT_SMBUS_MEASUREMENT_INTERVAL_MS));
}
Example #8
0
int
PX4FLOW::collect()
{
    int ret = -EIO;

    /* read from the sensor */
    uint8_t val[I2C_FRAME_SIZE + I2C_INTEGRAL_FRAME_SIZE] = { 0 };

    perf_begin(_sample_perf);

    if (PX4FLOW_REG == 0x00) {
        ret = transfer(nullptr, 0, &val[0], I2C_FRAME_SIZE + I2C_INTEGRAL_FRAME_SIZE);
    }

    if (PX4FLOW_REG == 0x16) {
        ret = transfer(nullptr, 0, &val[0], I2C_INTEGRAL_FRAME_SIZE);
    }

    if (ret < 0) {
        DEVICE_DEBUG("error reading from sensor: %d", ret);
        perf_count(_comms_errors);
        perf_end(_sample_perf);
        return ret;
    }

    if (PX4FLOW_REG == 0) {
        memcpy(&f, val, I2C_FRAME_SIZE);
        memcpy(&f_integral, &(val[I2C_FRAME_SIZE]), I2C_INTEGRAL_FRAME_SIZE);
    }

    if (PX4FLOW_REG == 0x16) {
        memcpy(&f_integral, val, I2C_INTEGRAL_FRAME_SIZE);
    }


    struct optical_flow_s report;

    report.timestamp = hrt_absolute_time();
    report.pixel_flow_x_integral = static_cast<float>(f_integral.pixel_flow_x_integral) / 10000.0f;//convert to radians
    report.pixel_flow_y_integral = static_cast<float>(f_integral.pixel_flow_y_integral) / 10000.0f;//convert to radians
    report.frame_count_since_last_readout = f_integral.frame_count_since_last_readout;
    report.ground_distance_m = static_cast<float>(f_integral.ground_distance) / 1000.0f;//convert to meters
    report.quality = f_integral.qual; //0:bad ; 255 max quality
    report.gyro_x_rate_integral = static_cast<float>(f_integral.gyro_x_rate_integral) / 10000.0f; //convert to radians
    report.gyro_y_rate_integral = static_cast<float>(f_integral.gyro_y_rate_integral) / 10000.0f; //convert to radians
    report.gyro_z_rate_integral = static_cast<float>(f_integral.gyro_z_rate_integral) / 10000.0f; //convert to radians
    report.integration_timespan = f_integral.integration_timespan; //microseconds
    report.time_since_last_sonar_update = f_integral.sonar_timestamp;//microseconds
    report.gyro_temperature = f_integral.gyro_temperature;//Temperature * 100 in centi-degrees Celsius

    report.sensor_id = 0;

    /* rotate measurements according to parameter */
    float zeroval = 0.0f;
    rotate_3f(_sensor_rotation, report.pixel_flow_x_integral, report.pixel_flow_y_integral, zeroval);

    if (_px4flow_topic == nullptr) {
        _px4flow_topic = orb_advertise(ORB_ID(optical_flow), &report);

    } else {
        /* publish it */
        orb_publish(ORB_ID(optical_flow), _px4flow_topic, &report);
    }

    /* publish to the distance_sensor topic as well */
    struct distance_sensor_s distance_report;
    distance_report.timestamp = report.timestamp;
    distance_report.min_distance = PX4FLOW_MIN_DISTANCE;
    distance_report.max_distance = PX4FLOW_MAX_DISTANCE;
    distance_report.current_distance = report.ground_distance_m;
    distance_report.covariance = 0.0f;
    distance_report.type = distance_sensor_s::MAV_DISTANCE_SENSOR_ULTRASOUND;
    /* TODO: the ID needs to be properly set */
    distance_report.id = 0;
    distance_report.orientation = 8;

    orb_publish(ORB_ID(distance_sensor), _distance_sensor_topic, &distance_report);

    /* post a report to the ring */
    if (_reports->force(&report)) {
        perf_count(_buffer_overflows);
    }

    /* notify anyone waiting for data */
    poll_notify(POLLIN);

    ret = OK;

    perf_end(_sample_perf);
    return ret;
}
Example #9
0
void
MPU9250::measure()
{
	if (hrt_absolute_time() < _reset_wait) {
		// we're waiting for a reset to complete
		return;
	}

	struct MPUReport mpu_report;

	struct Report {
		int16_t		accel_x;
		int16_t		accel_y;
		int16_t		accel_z;
		int16_t		temp;
		int16_t		gyro_x;
		int16_t		gyro_y;
		int16_t		gyro_z;
	} report;

	/* start measuring */
	perf_begin(_sample_perf);

	/*
	 * Fetch the full set of measurements from the MPU9250 in one pass.
	 */
	mpu_report.cmd = DIR_READ | MPUREG_INT_STATUS;

	// sensor transfer at high clock speed
	set_frequency(MPU9250_HIGH_BUS_SPEED);

	if (OK != transfer((uint8_t *)&mpu_report, ((uint8_t *)&mpu_report), sizeof(mpu_report))) {
		return;
	}

	check_registers();

	if (check_duplicate(&mpu_report.accel_x[0])) {
		return;
	}

	_mag->measure(mpu_report.mag);

	/*
	 * Convert from big to little endian
	 */
	report.accel_x = int16_t_from_bytes(mpu_report.accel_x);
	report.accel_y = int16_t_from_bytes(mpu_report.accel_y);
	report.accel_z = int16_t_from_bytes(mpu_report.accel_z);
	report.temp    = int16_t_from_bytes(mpu_report.temp);
	report.gyro_x  = int16_t_from_bytes(mpu_report.gyro_x);
	report.gyro_y  = int16_t_from_bytes(mpu_report.gyro_y);
	report.gyro_z  = int16_t_from_bytes(mpu_report.gyro_z);

	if (check_null_data((uint32_t *)&report, sizeof(report) / 4)) {
		return;
	}

	if (_register_wait != 0) {
		// we are waiting for some good transfers before using the sensor again
		// We still increment _good_transfers, but don't return any data yet
		_register_wait--;
		return;
	}

	/*
	 * Swap axes and negate y
	 */
	int16_t accel_xt = report.accel_y;
	int16_t accel_yt = ((report.accel_x == -32768) ? 32767 : -report.accel_x);

	int16_t gyro_xt = report.gyro_y;
	int16_t gyro_yt = ((report.gyro_x == -32768) ? 32767 : -report.gyro_x);

	/*
	 * Apply the swap
	 */
	report.accel_x = accel_xt;
	report.accel_y = accel_yt;
	report.gyro_x = gyro_xt;
	report.gyro_y = gyro_yt;

	/*
	 * Report buffers.
	 */
	accel_report		arb;
	gyro_report		grb;

	/*
	 * Adjust and scale results to m/s^2.
	 */
	grb.timestamp = arb.timestamp = hrt_absolute_time();

	// report the error count as the sum of the number of bad
	// transfers and bad register reads. This allows the higher
	// level code to decide if it should use this sensor based on
	// whether it has had failures
	grb.error_count = arb.error_count = perf_event_count(_bad_transfers) + perf_event_count(_bad_registers);

	/*
	 * 1) Scale raw value to SI units using scaling from datasheet.
	 * 2) Subtract static offset (in SI units)
	 * 3) Scale the statically calibrated values with a linear
	 *    dynamically obtained factor
	 *
	 * Note: the static sensor offset is the number the sensor outputs
	 * 	 at a nominally 'zero' input. Therefore the offset has to
	 * 	 be subtracted.
	 *
	 *	 Example: A gyro outputs a value of 74 at zero angular rate
	 *	 	  the offset is 74 from the origin and subtracting
	 *		  74 from all measurements centers them around zero.
	 */

	/* NOTE: Axes have been swapped to match the board a few lines above. */

	arb.x_raw = report.accel_x;
	arb.y_raw = report.accel_y;
	arb.z_raw = report.accel_z;

	float xraw_f = report.accel_x;
	float yraw_f = report.accel_y;
	float zraw_f = report.accel_z;

	// apply user specified rotation
	rotate_3f(_rotation, xraw_f, yraw_f, zraw_f);

	float x_in_new = ((xraw_f * _accel_range_scale) - _accel_scale.x_offset) * _accel_scale.x_scale;
	float y_in_new = ((yraw_f * _accel_range_scale) - _accel_scale.y_offset) * _accel_scale.y_scale;
	float z_in_new = ((zraw_f * _accel_range_scale) - _accel_scale.z_offset) * _accel_scale.z_scale;

	arb.x = _accel_filter_x.apply(x_in_new);
	arb.y = _accel_filter_y.apply(y_in_new);
	arb.z = _accel_filter_z.apply(z_in_new);

	math::Vector<3> aval(x_in_new, y_in_new, z_in_new);
	math::Vector<3> aval_integrated;

	bool accel_notify = _accel_int.put(arb.timestamp, aval, aval_integrated, arb.integral_dt);
	arb.x_integral = aval_integrated(0);
	arb.y_integral = aval_integrated(1);
	arb.z_integral = aval_integrated(2);

	arb.scaling = _accel_range_scale;
	arb.range_m_s2 = _accel_range_m_s2;

	_last_temperature = (report.temp) / 361.0f + 35.0f;

	arb.temperature_raw = report.temp;
	arb.temperature = _last_temperature;

	grb.x_raw = report.gyro_x;
	grb.y_raw = report.gyro_y;
	grb.z_raw = report.gyro_z;

	xraw_f = report.gyro_x;
	yraw_f = report.gyro_y;
	zraw_f = report.gyro_z;

	// apply user specified rotation
	rotate_3f(_rotation, xraw_f, yraw_f, zraw_f);

	float x_gyro_in_new = ((xraw_f * _gyro_range_scale) - _gyro_scale.x_offset) * _gyro_scale.x_scale;
	float y_gyro_in_new = ((yraw_f * _gyro_range_scale) - _gyro_scale.y_offset) * _gyro_scale.y_scale;
	float z_gyro_in_new = ((zraw_f * _gyro_range_scale) - _gyro_scale.z_offset) * _gyro_scale.z_scale;

	grb.x = _gyro_filter_x.apply(x_gyro_in_new);
	grb.y = _gyro_filter_y.apply(y_gyro_in_new);
	grb.z = _gyro_filter_z.apply(z_gyro_in_new);

	math::Vector<3> gval(x_gyro_in_new, y_gyro_in_new, z_gyro_in_new);
	math::Vector<3> gval_integrated;

	bool gyro_notify = _gyro_int.put(arb.timestamp, gval, gval_integrated, grb.integral_dt);
	grb.x_integral = gval_integrated(0);
	grb.y_integral = gval_integrated(1);
	grb.z_integral = gval_integrated(2);

	grb.scaling = _gyro_range_scale;
	grb.range_rad_s = _gyro_range_rad_s;

	grb.temperature_raw = report.temp;
	grb.temperature = _last_temperature;

	_accel_reports->force(&arb);
	_gyro_reports->force(&grb);

	/* notify anyone waiting for data */
	if (accel_notify) {
		poll_notify(POLLIN);
	}

	if (gyro_notify) {
		_gyro->parent_poll_notify();
	}

	if (accel_notify && !(_pub_blocked)) {
		/* log the time of this report */
		perf_begin(_controller_latency_perf);
		/* publish it */
		orb_publish(ORB_ID(sensor_accel), _accel_topic, &arb);
	}

	if (gyro_notify && !(_pub_blocked)) {
		/* publish it */
		orb_publish(ORB_ID(sensor_gyro), _gyro->_gyro_topic, &grb);
	}

	/* stop measuring */
	perf_end(_sample_perf);
}
Example #10
0
int
HMC5883::collect()
{
#pragma pack(push, 1)
	struct { /* status register and data as read back from the device */
		uint8_t		x[2];
		uint8_t		z[2];
		uint8_t		y[2];
	}	hmc_report;
#pragma pack(pop)
	struct {
		int16_t		x, y, z;
	} report;
	int	ret = -EIO;
	uint8_t	cmd;


	perf_begin(_sample_perf);

	/* this should be fairly close to the end of the measurement, so the best approximation of the time */
	_reports[_next_report].timestamp = hrt_absolute_time();

	/*
	 * @note  We could read the status register here, which could tell us that
	 *        we were too early and that the output registers are still being
	 *        written.  In the common case that would just slow us down, and
	 *        we're better off just never being early.
	 */

	/* get measurements from the device */
	cmd = ADDR_DATA_OUT_X_MSB;
	ret = transfer(&cmd, 1, (uint8_t *)&hmc_report, sizeof(hmc_report));

	if (ret != OK) {
		perf_count(_comms_errors);
		debug("data/status read error");
		goto out;
	}

	/* swap the data we just received */
	report.x = (((int16_t)hmc_report.x[0]) << 8) + hmc_report.x[1];
	report.y = (((int16_t)hmc_report.y[0]) << 8) + hmc_report.y[1];
	report.z = (((int16_t)hmc_report.z[0]) << 8) + hmc_report.z[1];

	/*
	 * If any of the values are -4096, there was an internal math error in the sensor.
	 * Generalise this to a simple range check that will also catch some bit errors.
	 */
	if ((abs(report.x) > 2048) ||
	    (abs(report.y) > 2048) ||
	    (abs(report.z) > 2048))
		goto out;

	/*
	 * RAW outputs
	 *
	 * to align the sensor axes with the board, x and y need to be flipped
	 * and y needs to be negated
	 */
	_reports[_next_report].x_raw = report.y;
	_reports[_next_report].y_raw = ((report.x == -32768) ? 32767 : -report.x);
	/* z remains z */
	_reports[_next_report].z_raw = report.z;

	/* scale values for output */

	/*
	 * 1) Scale raw value to SI units using scaling from datasheet.
	 * 2) Subtract static offset (in SI units)
	 * 3) Scale the statically calibrated values with a linear
	 *    dynamically obtained factor
	 *
	 * Note: the static sensor offset is the number the sensor outputs
	 * 	 at a nominally 'zero' input. Therefore the offset has to
	 * 	 be subtracted.
	 *
	 *	 Example: A gyro outputs a value of 74 at zero angular rate
	 *	 	  the offset is 74 from the origin and subtracting
	 *		  74 from all measurements centers them around zero.
	 */

	/* to align the sensor axes with the board, x and y need to be flipped */
	_reports[_next_report].x = ((report.y * _range_scale) - _scale.x_offset) * _scale.x_scale;
	/* flip axes and negate value for y */
	_reports[_next_report].y = ((((report.x == -32768) ? 32767 : -report.x) * _range_scale) - _scale.y_offset) * _scale.y_scale;
	/* z remains z */
	_reports[_next_report].z = ((report.z * _range_scale) - _scale.z_offset) * _scale.z_scale;

	/* publish it */
	orb_publish(ORB_ID(sensor_mag), _mag_topic, &_reports[_next_report]);

	/* post a report to the ring - note, not locked */
	INCREMENT(_next_report, _num_reports);

	/* if we are running up against the oldest report, toss it */
	if (_next_report == _oldest_report) {
		perf_count(_buffer_overflows);
		INCREMENT(_oldest_report, _num_reports);
	}

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	ret = OK;

out:
	perf_end(_sample_perf);
	return ret;
}
Example #11
0
void
FXAS21002C::measure()
{
	/* status register and data as read back from the device */

#pragma pack(push, 1)
	struct {
		uint8_t		cmd;
		uint8_t		status;
		int16_t		x;
		int16_t		y;
		int16_t		z;
	} raw_gyro_report;
#pragma pack(pop)

	sensor_gyro_s gyro_report;

	/* start the performance counter */
	perf_begin(_sample_perf);

	check_registers();

	if (_register_wait != 0) {
		// we are waiting for some good transfers before using
		// the sensor again.
		_register_wait--;
		perf_end(_sample_perf);
		return;
	}

	/* fetch data from the sensor */
	memset(&raw_gyro_report, 0, sizeof(raw_gyro_report));
	raw_gyro_report.cmd = DIR_READ(FXAS21002C_STATUS);
	transfer((uint8_t *)&raw_gyro_report, (uint8_t *)&raw_gyro_report, sizeof(raw_gyro_report));

	if (!(raw_gyro_report.status & DR_STATUS_ZYXDR)) {
		perf_end(_sample_perf);
		perf_count(_duplicates);
		return;
	}

	/*
	 * The TEMP register contains an 8-bit 2's complement temperature value with a range
	 * of –128 °C to +127 °C and a scaling of 1 °C/LSB. The temperature data is only
	 * compensated (factory trim values applied) when the device is operating in the Active
	 * mode and actively measuring the angular rate.
	 */

	if ((_read % _current_rate) == 0) {
		_last_temperature = read_reg(FXAS21002C_TEMP) * 1.0f;
		gyro_report.temperature = _last_temperature;
	}

	/*
	 * 1) Scale raw value to SI units using scaling from datasheet.
	 * 2) Subtract static offset (in SI units)
	 * 3) Scale the statically calibrated values with a linear
	 *    dynamically obtained factor
	 *
	 * Note: the static sensor offset is the number the sensor outputs
	 * 	 at a nominally 'zero' input. Therefore the offset has to
	 * 	 be subtracted.
	 *
	 *	 Example: A gyro outputs a value of 74 at zero angular rate
	 *	 	  the offset is 74 from the origin and subtracting
	 *		  74 from all measurements centers them around zero.
	 */

	gyro_report.timestamp = hrt_absolute_time();

	// report the error count as the number of bad
	// register reads. This allows the higher level
	// code to decide if it should use this sensor based on
	// whether it has had failures
	gyro_report.error_count = perf_event_count(_bad_registers);

	gyro_report.x_raw = swap16(raw_gyro_report.x);
	gyro_report.y_raw = swap16(raw_gyro_report.y);
	gyro_report.z_raw = swap16(raw_gyro_report.z);

	float xraw_f = gyro_report.x_raw;
	float yraw_f = gyro_report.y_raw;
	float zraw_f = gyro_report.z_raw;

	// apply user specified rotation
	rotate_3f(_rotation, xraw_f, yraw_f, zraw_f);

	float x_in_new = ((xraw_f * _gyro_range_scale) - _gyro_scale.x_offset) * _gyro_scale.x_scale;
	float y_in_new = ((yraw_f * _gyro_range_scale) - _gyro_scale.y_offset) * _gyro_scale.y_scale;
	float z_in_new = ((zraw_f * _gyro_range_scale) - _gyro_scale.z_offset) * _gyro_scale.z_scale;

	gyro_report.x = _gyro_filter_x.apply(x_in_new);
	gyro_report.y = _gyro_filter_y.apply(y_in_new);
	gyro_report.z = _gyro_filter_z.apply(z_in_new);

	matrix::Vector3f gval(x_in_new, y_in_new, z_in_new);
	matrix::Vector3f gval_integrated;

	bool gyro_notify = _gyro_int.put(gyro_report.timestamp, gval, gval_integrated, gyro_report.integral_dt);
	gyro_report.x_integral = gval_integrated(0);
	gyro_report.y_integral = gval_integrated(1);
	gyro_report.z_integral = gval_integrated(2);

	gyro_report.scaling = _gyro_range_scale;

	/* return device ID */
	gyro_report.device_id = _device_id.devid;


	_reports->force(&gyro_report);

	/* notify anyone waiting for data */
	if (gyro_notify) {
		poll_notify(POLLIN);

		if (!(_pub_blocked)) {
			/* publish it */
			orb_publish(ORB_ID(sensor_gyro), _gyro_topic, &gyro_report);
		}
	}

	_read++;

	/* stop the perf counter */
	perf_end(_sample_perf);
}
void
IIS328DQ::measure()
{
	/* status register and data as read back from the device */
	struct {
		uint8_t		cmd;
		uint8_t		status;
		int16_t		x;
		int16_t		y;
		int16_t		z;
	} raw_accel_report;
    uint8_t raw_data[8];

	accel_report accel_report = {0};

	/* start the performance counter */
	perf_begin(_sample_perf);

	check_registers();

	if (_register_wait != 0) {
		// we are waiting for some good transfers before using
		// the sensor again.
		_register_wait--;
		perf_end(_sample_perf);
		return;
	}

	/* fetch data from the sensor */
	memset(&raw_data, 0, sizeof(raw_data));
	raw_data[0] = ADDR_STATUS_REG | DIR_READ | ADDR_INCREMENT;
	spi_transfer(&iis328dq_spi, raw_data, raw_data, sizeof(raw_data));

    raw_accel_report.status = raw_data[1];
    raw_accel_report.x = ((int16_t)raw_data[3] << 8) | raw_data[2];
    raw_accel_report.y = ((int16_t)raw_data[5] << 8) | raw_data[4];
    raw_accel_report.z = ((int16_t)raw_data[7] << 8) | raw_data[6];

    if (!(raw_accel_report.status & STATUS_ZYXDA)) {
		perf_end(_sample_perf);
		perf_count(_duplicates);
		return;
    }

	/*
	 * 1) Scale raw value to SI units using scaling from datasheet.
	 * 2) Subtract static offset (in SI units)
	 * 3) Scale the statically calibrated values with a linear
	 *    dynamically obtained factor
	 *
	 * Note: the static sensor offset is the number the sensor outputs
	 * 	 at a nominally 'zero' input. Therefore the offset has to
	 * 	 be subtracted.
	 *
	 *	 Example: A gyro outputs a value of 74 at zero angular rate
	 *	 	  the offset is 74 from the origin and subtracting
	 *		  74 from all measurements centers them around zero.
	 */


	accel_report.timestamp = hrt_absolute_time();

	// report the error count as the sum of the number of bad
	// register reads and bad values. This allows the higher level
	// code to decide if it should use this sensor based on
	// whether it has had failures
    accel_report.error_count = perf_event_count(_bad_registers) + perf_event_count(_bad_values);


	accel_report.x_raw = raw_accel_report.x;
	accel_report.y_raw = raw_accel_report.y;
	accel_report.z_raw = raw_accel_report.z;

	float xraw_f = raw_accel_report.x;
	float yraw_f = raw_accel_report.y;
	float zraw_f = raw_accel_report.z;

	// apply user specified rotation
	rotate_3f(_rotation, xraw_f, yraw_f, zraw_f);

	float x_in_new = ((xraw_f * _accel_range_scale) - _accel_scale.x_offset) * _accel_scale.x_scale;
	float y_in_new = ((yraw_f * _accel_range_scale) - _accel_scale.y_offset) * _accel_scale.y_scale;
	float z_in_new = ((zraw_f * _accel_range_scale) - _accel_scale.z_offset) * _accel_scale.z_scale;

	/*
	  we have logs where the accelerometers get stuck at a fixed
	  large value. We want to detect this and mark the sensor as
	  being faulty
	 */
	if (fabsf(_last_accel[0] - x_in_new) < 0.001f &&
	    fabsf(_last_accel[1] - y_in_new) < 0.001f &&
	    fabsf(_last_accel[2] - z_in_new) < 0.001f &&
	    fabsf(x_in_new) > 20 &&
	    fabsf(y_in_new) > 20 &&
	    fabsf(z_in_new) > 20) {
		_constant_accel_count += 1;
	} else {
		_constant_accel_count = 0;
	}
	if (_constant_accel_count > 100) {
		// we've had 100 constant accel readings with large
		// values. The sensor is almost certainly dead. We
		// will raise the error_count so that the top level
		// flight code will know to avoid this sensor, but
		// we'll still give the data so that it can be logged
		// and viewed
		perf_count(_bad_values);
		_constant_accel_count = 0;
	}

	_last_accel[0] = x_in_new;
	_last_accel[1] = y_in_new;
	_last_accel[2] = z_in_new;

	accel_report.x = _accel_filter_x.apply(x_in_new);
	accel_report.y = _accel_filter_y.apply(y_in_new);
	accel_report.z = _accel_filter_z.apply(z_in_new);

	accel_report.scaling = _accel_range_scale;
	accel_report.range_m_s2 = _accel_range_m_s2;

    //pilot_warn("accel data:rawxyz[%04x,%04x,%04x] size=%d\n", accel_report.x_raw, accel_report.y_raw, accel_report.z_raw, sizeof(raw_accel_report));
	ringbuf_force(_reports, &accel_report, sizeof(accel_report));

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

//	if (!(_pub_blocked)) 
    {
		/* publish it */
		orb_publish(ORB_ID(sensor_accel), _accel_topic, &accel_report);
	}

	_read++;
    
	/* stop the perf counter */
	perf_end(_sample_perf);
}
Example #13
0
int
HMC5883::collect()
{
#pragma pack(push, 1)
	struct { /* status register and data as read back from the device */
		uint8_t		x[2];
		uint8_t		z[2];
		uint8_t		y[2];
	}	hmc_report;
#pragma pack(pop)
	struct {
		int16_t		x, y, z;
	} report;

	int	ret;
	uint8_t check_counter;

	perf_begin(_sample_perf);
	struct mag_report new_report;
	bool sensor_is_onboard = false;

	float xraw_f;
	float yraw_f;
	float zraw_f;

	/* this should be fairly close to the end of the measurement, so the best approximation of the time */
	new_report.timestamp = hrt_absolute_time();
	new_report.error_count = perf_event_count(_comms_errors);
	new_report.range_ga = _range_ga;
	new_report.scaling = _range_scale;
	new_report.device_id = _device_id.devid;

	/*
	 * @note  We could read the status register here, which could tell us that
	 *        we were too early and that the output registers are still being
	 *        written.  In the common case that would just slow us down, and
	 *        we're better off just never being early.
	 */

	/* get measurements from the device */
	ret = _interface->read(ADDR_DATA_OUT_X_MSB, (uint8_t *)&hmc_report, sizeof(hmc_report));

	if (ret != OK) {
		perf_count(_comms_errors);
		DEVICE_DEBUG("data/status read error");
		goto out;
	}

	/* swap the data we just received */
	report.x = (((int16_t)hmc_report.x[0]) << 8) + hmc_report.x[1];
	report.y = (((int16_t)hmc_report.y[0]) << 8) + hmc_report.y[1];
	report.z = (((int16_t)hmc_report.z[0]) << 8) + hmc_report.z[1];

	/*
	 * If any of the values are -4096, there was an internal math error in the sensor.
	 * Generalise this to a simple range check that will also catch some bit errors.
	 */
	if ((abs(report.x) > 2048) ||
	    (abs(report.y) > 2048) ||
	    (abs(report.z) > 2048)) {
		perf_count(_comms_errors);
		goto out;
	}

	/* get measurements from the device */
	new_report.temperature = 0;

	if (_conf_reg & HMC5983_TEMP_SENSOR_ENABLE) {
		/*
		  if temperature compensation is enabled read the
		  temperature too.

		  We read the temperature every 10 samples to avoid
		  excessive I2C traffic
		 */
		if (_temperature_counter++ == 10) {
			uint8_t raw_temperature[2];

			_temperature_counter = 0;

			ret = _interface->read(ADDR_TEMP_OUT_MSB,
					       raw_temperature, sizeof(raw_temperature));

			if (ret == OK) {
				int16_t temp16 = (((int16_t)raw_temperature[0]) << 8) +
						 raw_temperature[1];
				new_report.temperature = 25 + (temp16 / (16 * 8.0f));
				_temperature_error_count = 0;

			} else {
				_temperature_error_count++;

				if (_temperature_error_count == 10) {
					/*
					  it probably really is an old HMC5883,
					  and can't do temperature. Disable it
					*/
					_temperature_error_count = 0;
					DEVICE_DEBUG("disabling temperature compensation");
					set_temperature_compensation(0);
				}
			}

		} else {
			new_report.temperature = _last_report.temperature;
		}
	}

	/*
	 * RAW outputs
	 *
	 * to align the sensor axes with the board, x and y need to be flipped
	 * and y needs to be negated
	 */
	new_report.x_raw = report.y;
	new_report.y_raw = -report.x;
	/* z remains z */
	new_report.z_raw = report.z;

	/* scale values for output */

	// XXX revisit for SPI part, might require a bus type IOCTL
	unsigned dummy;
	sensor_is_onboard = !_interface->ioctl(MAGIOCGEXTERNAL, dummy);
	new_report.is_external = !sensor_is_onboard;

	if (sensor_is_onboard) {
		// convert onboard so it matches offboard for the
		// scaling below
		report.y = -report.y;
		report.x = -report.x;
	}

	/* the standard external mag by 3DR has x pointing to the
	 * right, y pointing backwards, and z down, therefore switch x
	 * and y and invert y */
	xraw_f = -report.y;
	yraw_f = report.x;
	zraw_f = report.z;

	// apply user specified rotation
	rotate_3f(_rotation, xraw_f, yraw_f, zraw_f);

	new_report.x = ((xraw_f * _range_scale) - _scale.x_offset) * _scale.x_scale;
	/* flip axes and negate value for y */
	new_report.y = ((yraw_f * _range_scale) - _scale.y_offset) * _scale.y_scale;
	/* z remains z */
	new_report.z = ((zraw_f * _range_scale) - _scale.z_offset) * _scale.z_scale;

	if (!(_pub_blocked)) {

		if (_mag_topic != nullptr) {
			/* publish it */
			orb_publish(ORB_ID(sensor_mag), _mag_topic, &new_report);

		} else {
			_mag_topic = orb_advertise_multi(ORB_ID(sensor_mag), &new_report,
							 &_orb_class_instance, (sensor_is_onboard) ? ORB_PRIO_HIGH : ORB_PRIO_MAX);

			if (_mag_topic == nullptr) {
				DEVICE_DEBUG("ADVERT FAIL");
			}
		}
	}

	_last_report = new_report;

	/* post a report to the ring */
	_reports->force(&new_report);

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	/*
	  periodically check the range register and configuration
	  registers. With a bad I2C cable it is possible for the
	  registers to become corrupt, leading to bad readings. It
	  doesn't happen often, but given the poor cables some
	  vehicles have it is worth checking for.
	 */
	check_counter = perf_event_count(_sample_perf) % 256;

	if (check_counter == 0) {
		check_range();
	}

	if (check_counter == 128) {
		check_conf();
	}

	ret = OK;

out:
	perf_end(_sample_perf);
	return ret;
}
Example #14
0
int
LIS3MDL::collect()
{
#pragma pack(push, 1)
	struct { /* status register and data as read back from the device */
		uint8_t		x[2];
		uint8_t		y[2];
		uint8_t		z[2];
		uint8_t		t[2];
	}	lis_report;

	struct {
		int16_t		x;
		int16_t		y;
		int16_t		z;
		int16_t		t;
	} report;
#pragma pack(pop)

	int	ret;
//	uint8_t check_counter;

	perf_begin(_sample_perf);
	struct mag_report new_report;
	bool sensor_is_onboard = false;

	float xraw_f;
	float yraw_f;
	float zraw_f;

	/* this should be fairly close to the end of the measurement, so the best approximation of the time */
	new_report.timestamp = hrt_absolute_time();
	new_report.error_count = perf_event_count(_comms_errors);

	/*
	 * @note  We could read the status register here, which could tell us that
	 *        we were too early and that the output registers are still being
	 *        written.  In the common case that would just slow us down, and
	 *        we're better off just never being early.
	 */

	/* get measurements from the device */
	ret = _interface->read(ADDR_OUT_X_L, (uint8_t *)&lis_report, sizeof(lis_report));

	if (ret != OK) {
		perf_count(_comms_errors);
		DEVICE_DEBUG("data/status read error");
		goto out;
	}

	/* convert the data we just received */
	report.x = (((int16_t)lis_report.x[1]) << 8) + lis_report.x[0];
	report.y = (((int16_t)lis_report.y[1]) << 8) + lis_report.y[0];
	report.z = (((int16_t)lis_report.z[1]) << 8) + lis_report.z[0];
	report.t = (((int16_t)lis_report.t[1]) << 8) + lis_report.t[0];

	/* get measurements from the device */
	new_report.temperature = report.t;
	new_report.temperature = 25 + (report.t / (16 * 8.0f));

	// XXX revisit for SPI part, might require a bus type IOCTL

	unsigned dummy;
	sensor_is_onboard = !_interface->ioctl(MAGIOCGEXTERNAL, dummy);

	/*
	 * RAW outputs
	 *
	 */
	new_report.x_raw = report.x;
	new_report.y_raw = report.y;
	new_report.z_raw = report.z;

	/* the LIS3MDL mag on Pixhawk Pro by Drotek has x pointing towards,
	 * y pointing to the right, and z down, therefore no switch needed,
	 * it is better to have no artificial rotation inside the
	 * driver and then use the startup script with -R command with the
	 * real rotation between the sensor and body frame */
	xraw_f = report.x;
	yraw_f = report.y;
	zraw_f = report.z;

	// apply user specified rotation
	rotate_3f(_rotation, xraw_f, yraw_f, zraw_f);

	new_report.x = ((xraw_f * _range_scale) - _scale.x_offset) * _scale.x_scale;
	/* flip axes and negate value for y */
	new_report.y = ((yraw_f * _range_scale) - _scale.y_offset) * _scale.y_scale;
	/* z remains z */
	new_report.z = ((zraw_f * _range_scale) - _scale.z_offset) * _scale.z_scale;

	if (!(_pub_blocked)) {

		if (_mag_topic != nullptr) {
			/* publish it */
			orb_publish(ORB_ID(sensor_mag), _mag_topic, &new_report);

		} else {
			_mag_topic = orb_advertise_multi(ORB_ID(sensor_mag), &new_report,
							 &_orb_class_instance, (sensor_is_onboard) ? ORB_PRIO_HIGH : ORB_PRIO_MAX);

			if (_mag_topic == nullptr) {
				DEVICE_DEBUG("ADVERT FAIL");
			}
		}
	}

	_last_report = new_report;

	/* post a report to the ring */
	if (_reports->force(&new_report)) {
		perf_count(_buffer_overflows);
	}

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	check_conf();

	ret = OK;

out:
	perf_end(_sample_perf);
	return ret;
}
Example #15
0
void
FXOS8700CQ_mag::parent_poll_notify()
{
	poll_notify(POLLIN);
}
Example #16
0
int
PMW3901::collect()
{
	int ret = OK;
	int16_t delta_x_raw, delta_y_raw;
	float delta_x, delta_y;

	perf_begin(_sample_perf);

	uint64_t timestamp = hrt_absolute_time();
	uint64_t dt_flow = timestamp - _previous_collect_timestamp;
	_previous_collect_timestamp = timestamp;

	_flow_dt_sum_usec += dt_flow;

	readMotionCount(delta_x_raw, delta_y_raw);

	_flow_sum_x += delta_x_raw;
	_flow_sum_y += delta_y_raw;

	// returns if the collect time has not been reached
	if (_flow_dt_sum_usec < _collect_time) {

		return ret;
	}

	delta_x = (float)_flow_sum_x / 500.0f;		// proportional factor + convert from pixels to radians
	delta_y = (float)_flow_sum_y / 500.0f;		// proportional factor + convert from pixels to radians

	struct optical_flow_s report;

	report.timestamp = timestamp;

	report.pixel_flow_x_integral = static_cast<float>(delta_x);
	report.pixel_flow_y_integral = static_cast<float>(delta_y);

	// rotate measurements in yaw from sensor frame to body frame according to parameter SENS_FLOW_ROT
	float zeroval = 0.0f;
	rotate_3f(_yaw_rotation, report.pixel_flow_x_integral, report.pixel_flow_y_integral, zeroval);
	rotate_3f(_yaw_rotation, report.gyro_x_rate_integral, report.gyro_y_rate_integral, report.gyro_z_rate_integral);

	report.frame_count_since_last_readout = 4;				//microseconds
	report.integration_timespan = _flow_dt_sum_usec; 		//microseconds

	report.sensor_id = 0;

	// This sensor doesn't provide any quality metric. However if the sensor is unable to calculate the optical flow it will
	// output 0 for the delta. Hence, we set the measurement to "invalid" (quality = 0) if the values are smaller than FLT_EPSILON
	if (fabsf(report.pixel_flow_x_integral) < FLT_EPSILON && fabsf(report.pixel_flow_y_integral) < FLT_EPSILON) {
		report.quality = 0;

	} else {
		report.quality = 255;
	}

	/* No gyro on this board */
	report.gyro_x_rate_integral = NAN;
	report.gyro_y_rate_integral = NAN;
	report.gyro_z_rate_integral = NAN;

	// set (conservative) specs according to datasheet
	report.max_flow_rate = 5.0f;       // Datasheet: 7.4 rad/s
	report.min_ground_distance = 0.1f; // Datasheet: 80mm
	report.max_ground_distance = 30.0f; // Datasheet: infinity

	_flow_dt_sum_usec = 0;
	_flow_sum_x = 0;
	_flow_sum_y = 0;

	if (_optical_flow_pub == nullptr) {

		_optical_flow_pub = orb_advertise(ORB_ID(optical_flow), &report);

	} else {

		orb_publish(ORB_ID(optical_flow), _optical_flow_pub, &report);
	}

	/* post a report to the ring */
	_reports->force(&report);

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	perf_end(_sample_perf);

	return ret;

}
void
LSM303D::mag_measure()
{
    /* status register and data as read back from the device */
#pragma pack(push, 1)
    struct {
        uint8_t		cmd;
        uint8_t		status;
        int16_t		x;
        int16_t		y;
        int16_t		z;
    } raw_mag_report;
#pragma pack(pop)

    mag_report		*mag_report = &_mag_reports[_next_mag_report];

    /* start the performance counter */
    perf_begin(_mag_sample_perf);

    /* fetch data from the sensor */
    raw_mag_report.cmd = ADDR_STATUS_M | DIR_READ | ADDR_INCREMENT;
    transfer((uint8_t *)&raw_mag_report, (uint8_t *)&raw_mag_report, sizeof(raw_mag_report));

    /*
     * 1) Scale raw value to SI units using scaling from datasheet.
     * 2) Subtract static offset (in SI units)
     * 3) Scale the statically calibrated values with a linear
     *    dynamically obtained factor
     *
     * Note: the static sensor offset is the number the sensor outputs
     * 	 at a nominally 'zero' input. Therefore the offset has to
     * 	 be subtracted.
     *
     *	 Example: A gyro outputs a value of 74 at zero angular rate
     *	 	  the offset is 74 from the origin and subtracting
     *		  74 from all measurements centers them around zero.
     */


    mag_report->timestamp = hrt_absolute_time();

    mag_report->x_raw = raw_mag_report.x;
    mag_report->y_raw = raw_mag_report.y;
    mag_report->z_raw = raw_mag_report.z;
    mag_report->x = ((mag_report->x_raw * _mag_range_scale) - _mag_scale.x_offset) * _mag_scale.x_scale;
    mag_report->y = ((mag_report->y_raw * _mag_range_scale) - _mag_scale.y_offset) * _mag_scale.y_scale;
    mag_report->z = ((mag_report->z_raw * _mag_range_scale) - _mag_scale.z_offset) * _mag_scale.z_scale;
    mag_report->scaling = _mag_range_scale;
    mag_report->range_ga = _mag_range_ga;

    /* post a report to the ring - note, not locked */
    INCREMENT(_next_mag_report, _num_mag_reports);

    /* if we are running up against the oldest report, fix it */
    if (_next_mag_report == _oldest_mag_report)
        INCREMENT(_oldest_mag_report, _num_mag_reports);

    /* XXX please check this poll_notify, is it the right one? */
    /* notify anyone waiting for data */
    poll_notify(POLLIN);

    /* publish for subscribers */
    orb_publish(ORB_ID(sensor_mag), _mag_topic, mag_report);

    /* stop the perf counter */
    perf_end(_mag_sample_perf);
}
Example #18
0
int
IST8310::collect()
{
#pragma pack(push, 1)
	struct { /* status register and data as read back from the device */
		uint8_t     x[2];
		uint8_t     y[2];
		uint8_t     z[2];
	} report_buffer;
#pragma pack(pop)
	struct {
		int16_t     x, y, z;
	} report;

	int ret;
	uint8_t check_counter;

	perf_begin(_sample_perf);
	struct mag_report new_report;
	const bool sensor_is_external = external();

	float xraw_f;
	float yraw_f;
	float zraw_f;

	/* this should be fairly close to the end of the measurement, so the best approximation of the time */
	new_report.timestamp = hrt_absolute_time();
	new_report.is_external = sensor_is_external;
	new_report.error_count = perf_event_count(_comms_errors);
	new_report.scaling = _range_scale;
	new_report.device_id = _device_id.devid;

	/*
	 * @note  We could read the status register here, which could tell us that
	 *        we were too early and that the output registers are still being
	 *        written.  In the common case that would just slow us down, and
	 *        we're better off just never being early.
	 */

	/* get measurements from the device */
	ret = read(ADDR_DATA_OUT_X_LSB, (uint8_t *)&report_buffer, sizeof(report_buffer));

	if (ret != OK) {
		perf_count(_comms_errors);
		DEVICE_DEBUG("I2C read error");
		goto out;
	}

	/* swap the data we just received */
	report.x = (((int16_t)report_buffer.x[1]) << 8) | (int16_t)report_buffer.x[0];
	report.y = (((int16_t)report_buffer.y[1]) << 8) | (int16_t)report_buffer.y[0];
	report.z = (((int16_t)report_buffer.z[1]) << 8) | (int16_t)report_buffer.z[0];


	/*
	 * Check if value makes sense according to the FSR and Resolution of
	 * this sensor, discarding outliers
	 */
	if (report.x > IST8310_MAX_VAL_XY || report.x < IST8310_MIN_VAL_XY ||
	    report.y > IST8310_MAX_VAL_XY || report.y < IST8310_MIN_VAL_XY ||
	    report.z > IST8310_MAX_VAL_Z  || report.z < IST8310_MIN_VAL_Z) {
		perf_count(_range_errors);
		DEVICE_DEBUG("data/status read error");
		goto out;
	}

	/* temperature measurement is not available on IST8310 */
	new_report.temperature = 0;

	/*
	 * raw outputs
	 *
	 * Sensor doesn't follow right hand rule, swap x and y to make it obey
	 * it.
	 */
	new_report.x_raw = report.y;
	new_report.y_raw = report.x;
	new_report.z_raw = report.z;

	/* scale values for output */
	xraw_f = report.y;
	yraw_f = report.x;
	zraw_f = report.z;

	/* apply user specified rotation */
	rotate_3f(_rotation, xraw_f, yraw_f, zraw_f);
	new_report.x = ((xraw_f * _range_scale) - _scale.x_offset) * _scale.x_scale;
	new_report.y = ((yraw_f * _range_scale) - _scale.y_offset) * _scale.y_scale;
	new_report.z = ((zraw_f * _range_scale) - _scale.z_offset) * _scale.z_scale;

	if (!(_pub_blocked)) {

		if (_mag_topic != nullptr) {
			/* publish it */
			orb_publish(ORB_ID(sensor_mag), _mag_topic, &new_report);

		} else {
			_mag_topic = orb_advertise_multi(ORB_ID(sensor_mag), &new_report,
							 &_orb_class_instance, sensor_is_external ? ORB_PRIO_MAX : ORB_PRIO_HIGH);

			if (_mag_topic == nullptr) {
				DEVICE_DEBUG("ADVERT FAIL");
			}
		}
	}

	_last_report = new_report;

	/* post a report to the ring */
	_reports->force(&new_report);

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	/*
	  periodically check the range register and configuration
	  registers. With a bad I2C cable it is possible for the
	  registers to become corrupt, leading to bad readings. It
	  doesn't happen often, but given the poor cables some
	  vehicles have it is worth checking for.
	 */
	check_counter = perf_event_count(_sample_perf) % 256;

	if (check_counter == 128) {
		check_conf();
	}

	ret = OK;

out:
	perf_end(_sample_perf);
	return ret;
}
Example #19
0
void
L3GD20::measure()
{
	/* status register and data as read back from the device */
#pragma pack(push, 1)
	struct {
		uint8_t		cmd;
		int8_t		temp;
		uint8_t		status;
		int16_t		x;
		int16_t		y;
		int16_t		z;
	} raw_report;
#pragma pack(pop)

	gyro_report report;

	/* start the performance counter */
	perf_begin(_sample_perf);

        check_registers();

#if L3GD20_USE_DRDY
	// if the gyro doesn't have any data ready then re-schedule
	// for 100 microseconds later. This ensures we don't double
	// read a value and then miss the next value
	if (_bus == PX4_SPI_BUS_SENSORS && stm32_gpioread(GPIO_EXTI_GYRO_DRDY) == 0) {
		perf_count(_reschedules);
		hrt_call_delay(&_call, 100);
                perf_end(_sample_perf);
		return;
	}
#endif

	/* fetch data from the sensor */
	memset(&raw_report, 0, sizeof(raw_report));
	raw_report.cmd = ADDR_OUT_TEMP | DIR_READ | ADDR_INCREMENT;
	transfer((uint8_t *)&raw_report, (uint8_t *)&raw_report, sizeof(raw_report));

#if L3GD20_USE_DRDY
        if (_bus == PX4_SPI_BUS_SENSORS && (raw_report.status & 0xF) != 0xF) {
            /*
              we waited for DRDY, but did not see DRDY on all axes
              when we captured. That means a transfer error of some sort
             */
            perf_count(_errors);
            return;
        }
#endif
	/*
	 * 1) Scale raw value to SI units using scaling from datasheet.
	 * 2) Subtract static offset (in SI units)
	 * 3) Scale the statically calibrated values with a linear
	 *    dynamically obtained factor
	 *
	 * Note: the static sensor offset is the number the sensor outputs
	 * 	 at a nominally 'zero' input. Therefore the offset has to
	 * 	 be subtracted.
	 *
	 *	 Example: A gyro outputs a value of 74 at zero angular rate
	 *	 	  the offset is 74 from the origin and subtracting
	 *		  74 from all measurements centers them around zero.
	 */
	report.timestamp = hrt_absolute_time();
        report.error_count = perf_event_count(_bad_registers);

	switch (_orientation) {

		case SENSOR_BOARD_ROTATION_000_DEG:
			/* keep axes in place */
			report.x_raw = raw_report.x;
			report.y_raw = raw_report.y;
			break;

		case SENSOR_BOARD_ROTATION_090_DEG:
			/* swap x and y */
			report.x_raw = raw_report.y;
			report.y_raw = raw_report.x;
			break;

		case SENSOR_BOARD_ROTATION_180_DEG:
			/* swap x and y and negate both */
			report.x_raw = ((raw_report.x == -32768) ? 32767 : -raw_report.x);
			report.y_raw = ((raw_report.y == -32768) ? 32767 : -raw_report.y);
			break;

		case SENSOR_BOARD_ROTATION_270_DEG:
			/* swap x and y and negate y */
			report.x_raw = raw_report.y;
			report.y_raw = ((raw_report.x == -32768) ? 32767 : -raw_report.x);
			break;
	}

	report.z_raw = raw_report.z;

	report.temperature_raw = raw_report.temp;

	report.x = ((report.x_raw * _gyro_range_scale) - _gyro_scale.x_offset) * _gyro_scale.x_scale;
	report.y = ((report.y_raw * _gyro_range_scale) - _gyro_scale.y_offset) * _gyro_scale.y_scale;
	report.z = ((report.z_raw * _gyro_range_scale) - _gyro_scale.z_offset) * _gyro_scale.z_scale;

	report.x = _gyro_filter_x.apply(report.x);
	report.y = _gyro_filter_y.apply(report.y);
	report.z = _gyro_filter_z.apply(report.z);

	report.temperature = L3GD20_TEMP_OFFSET_CELSIUS - raw_report.temp;

	// apply user specified rotation
	rotate_3f(_rotation, report.x, report.y, report.z);

	report.scaling = _gyro_range_scale;
	report.range_rad_s = _gyro_range_rad_s;

	_reports->force(&report);

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	/* publish for subscribers */
	if (!(_pub_blocked)) {
		/* publish it */
		orb_publish(ORB_ID(sensor_gyro), _gyro_topic, &report);
	}

	_read++;

	/* stop the perf counter */
	perf_end(_sample_perf);
}
Example #20
0
int
ETSAirspeed::collect()
{
	int	ret = -EIO;

	/* read from the sensor */
	uint8_t val[2] = {0, 0};

	perf_begin(_sample_perf);

	ret = transfer(nullptr, 0, &val[0], 2);

	if (ret < 0) {
		perf_count(_comms_errors);
		return ret;
	}

	uint16_t diff_pres_pa_raw = val[1] << 8 | val[0];

	if (diff_pres_pa_raw == 0) {
		// a zero value means the pressure sensor cannot give us a
		// value. We need to return, and not report a value or the
		// caller could end up using this value as part of an
		// average
		perf_count(_comms_errors);
		DEVICE_LOG("zero value from sensor");
		return -1;
	}

	// The raw value still should be compensated for the known offset
	diff_pres_pa_raw -= _diff_pres_offset;

	// Track maximum differential pressure measured (so we can work out top speed).
	if (diff_pres_pa_raw > _max_differential_pressure_pa) {
		_max_differential_pressure_pa = diff_pres_pa_raw;
	}

	differential_pressure_s report;
	report.timestamp = hrt_absolute_time();
	report.error_count = perf_event_count(_comms_errors);

	// XXX we may want to smooth out the readings to remove noise.
	report.differential_pressure_filtered_pa = diff_pres_pa_raw;
	report.differential_pressure_raw_pa = diff_pres_pa_raw;
	report.temperature = -1000.0f;
	report.max_differential_pressure_pa = _max_differential_pressure_pa;

	if (_airspeed_pub != nullptr && !(_pub_blocked)) {
		/* publish it */
		orb_publish(ORB_ID(differential_pressure), _airspeed_pub, &report);
	}

	new_report(report);

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	ret = OK;

	perf_end(_sample_perf);

	return ret;
}
Example #21
0
void
MPU9250_mag::measure(struct ak8963_regs data)
{
	bool mag_notify = true;

	if (check_duplicate((uint8_t *)&data.x) && !(data.st1 & 0x02)) {
		perf_count(_mag_duplicates);
		return;
	}

	/* monitor for if data overrun flag is ever set */
	if (data.st1 & 0x02) {
		perf_count(_mag_overruns);
	}

	/* monitor for if magnetic sensor overflow flag is ever set noting that st2
	 * is usually not even refreshed, but will always be in the same place in the
	 * mpu's buffers regardless, hence the actual count would be bogus
	 */
	if (data.st2 & 0x08) {
		perf_count(_mag_overflows);
	}

	mag_report	mrb;
	mrb.timestamp = hrt_absolute_time();

	/*
	 * Align axes - note the accel & gryo are also re-aligned so this
	 *              doesn't look obvious with the datasheet
	 */
	mrb.x_raw =  data.x;
	mrb.y_raw = -data.y;
	mrb.z_raw = -data.z;

	float xraw_f =  data.x;
	float yraw_f = -data.y;
	float zraw_f = -data.z;

	/* apply user specified rotation */
	rotate_3f(_parent->_rotation, xraw_f, yraw_f, zraw_f);

	mrb.x = ((xraw_f * _mag_range_scale * _mag_asa_x) - _mag_scale.x_offset) * _mag_scale.x_scale;
	mrb.y = ((yraw_f * _mag_range_scale * _mag_asa_y) - _mag_scale.y_offset) * _mag_scale.y_scale;
	mrb.z = ((zraw_f * _mag_range_scale * _mag_asa_z) - _mag_scale.z_offset) * _mag_scale.z_scale;
	mrb.range_ga = (float)48.0;
	mrb.scaling = _mag_range_scale;
	mrb.temperature = _parent->_last_temperature;

	mrb.error_count = perf_event_count(_mag_errors);

	_mag_reports->force(&mrb);

	/* notify anyone waiting for data */
	if (mag_notify) {
		poll_notify(POLLIN);
	}

	if (mag_notify && !(_pub_blocked)) {
		/* publish it */
		orb_publish(ORB_ID(sensor_mag), _mag_topic, &mrb);
	}
}
Example #22
0
void
LSM303D::measure()
{
	// if the accel doesn't have any data ready then re-schedule
	// for 100 microseconds later. This ensures we don't double
	// read a value and then miss the next value
	if (stm32_gpioread(GPIO_EXTI_ACCEL_DRDY) == 0) {
		perf_count(_accel_reschedules);
		hrt_call_delay(&_accel_call, 100);
		return;
	}
	if (read_reg(ADDR_CTRL_REG1) != _reg1_expected) {
		perf_count(_reg1_resets);
		reset();
		return;
	}

	/* status register and data as read back from the device */

#pragma pack(push, 1)
	struct {
		uint8_t		cmd;
		uint8_t		status;
		int16_t		x;
		int16_t		y;
		int16_t		z;
	} raw_accel_report;
#pragma pack(pop)

	accel_report accel_report;

	/* start the performance counter */
	perf_begin(_accel_sample_perf);

	/* fetch data from the sensor */
	memset(&raw_accel_report, 0, sizeof(raw_accel_report));
	raw_accel_report.cmd = ADDR_STATUS_A | DIR_READ | ADDR_INCREMENT;
	transfer((uint8_t *)&raw_accel_report, (uint8_t *)&raw_accel_report, sizeof(raw_accel_report));

	/*
	 * 1) Scale raw value to SI units using scaling from datasheet.
	 * 2) Subtract static offset (in SI units)
	 * 3) Scale the statically calibrated values with a linear
	 *    dynamically obtained factor
	 *
	 * Note: the static sensor offset is the number the sensor outputs
	 * 	 at a nominally 'zero' input. Therefore the offset has to
	 * 	 be subtracted.
	 *
	 *	 Example: A gyro outputs a value of 74 at zero angular rate
	 *	 	  the offset is 74 from the origin and subtracting
	 *		  74 from all measurements centers them around zero.
	 */


	accel_report.timestamp = hrt_absolute_time();
        accel_report.error_count = 0; // not reported

	accel_report.x_raw = raw_accel_report.x;
	accel_report.y_raw = raw_accel_report.y;
	accel_report.z_raw = raw_accel_report.z;

	float x_in_new = ((accel_report.x_raw * _accel_range_scale) - _accel_scale.x_offset) * _accel_scale.x_scale;
	float y_in_new = ((accel_report.y_raw * _accel_range_scale) - _accel_scale.y_offset) * _accel_scale.y_scale;
	float z_in_new = ((accel_report.z_raw * _accel_range_scale) - _accel_scale.z_offset) * _accel_scale.z_scale;

	accel_report.x = _accel_filter_x.apply(x_in_new);
	accel_report.y = _accel_filter_y.apply(y_in_new);
	accel_report.z = _accel_filter_z.apply(z_in_new);

	accel_report.scaling = _accel_range_scale;
	accel_report.range_m_s2 = _accel_range_m_s2;

	_accel_reports->force(&accel_report);

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	if (_accel_topic > 0 && !(_pub_blocked)) {
		/* publish it */
		orb_publish(ORB_ID(sensor_accel), _accel_topic, &accel_report);
	}

	_accel_read++;

	/* stop the perf counter */
	perf_end(_accel_sample_perf);
}
Example #23
0
int
MEASAirspeed::collect()
{
	int	ret = -EIO;

	/* read from the sensor */
	uint8_t val[4] = {0, 0, 0, 0};


	perf_begin(_sample_perf);

	ret = transfer(nullptr, 0, &val[0], 4);

	if (ret < 0) {
		perf_count(_comms_errors);
		perf_end(_sample_perf);
		return ret;
	}

	uint8_t status = (val[0] & 0xC0) >> 6;

	switch (status) {
	case 0:
		break;

	case 1:

	/* fallthrough */
	case 2:

	/* fallthrough */
	case 3:
		perf_count(_comms_errors);
		perf_end(_sample_perf);
		return -EAGAIN;
	}

	int16_t dp_raw = 0, dT_raw = 0;
	dp_raw = (val[0] << 8) + val[1];
	/* mask the used bits */
	dp_raw = 0x3FFF & dp_raw;
	dT_raw = (val[2] << 8) + val[3];
	dT_raw = (0xFFE0 & dT_raw) >> 5;
	float temperature = ((200.0f * dT_raw) / 2047) - 50;

	// Calculate differential pressure. As its centered around 8000
	// and can go positive or negative
	const float P_min = -1.0f;
	const float P_max = 1.0f;
	const float PSI_to_Pa = 6894.757f;
	/*
	  this equation is an inversion of the equation in the
	  pressure transfer function figure on page 4 of the datasheet

	  We negate the result so that positive differential pressures
	  are generated when the bottom port is used as the static
	  port on the pitot and top port is used as the dynamic port
	 */
	float diff_press_PSI = -((dp_raw - 0.1f * 16383) * (P_max - P_min) / (0.8f * 16383) + P_min);
	float diff_press_pa_raw = diff_press_PSI * PSI_to_Pa;

	// correct for 5V rail voltage if possible
	voltage_correction(diff_press_pa_raw, temperature);

	// the raw value still should be compensated for the known offset
	diff_press_pa_raw -= _diff_pres_offset;

	/*
	  With the above calculation the MS4525 sensor will produce a
	  positive number when the top port is used as a dynamic port
	  and bottom port is used as the static port
	 */

	struct differential_pressure_s report;

	/* track maximum differential pressure measured (so we can work out top speed). */
	if (diff_press_pa_raw > _max_differential_pressure_pa) {
		_max_differential_pressure_pa = diff_press_pa_raw;
	}

	report.timestamp = hrt_absolute_time();
	report.error_count = perf_event_count(_comms_errors);
	report.temperature = temperature;
	report.differential_pressure_filtered_pa =  _filter.apply(diff_press_pa_raw);

	report.differential_pressure_raw_pa = diff_press_pa_raw;
	report.max_differential_pressure_pa = _max_differential_pressure_pa;

	if (_airspeed_pub != nullptr && !(_pub_blocked)) {
		/* publish it */
		orb_publish(ORB_ID(differential_pressure), _airspeed_pub, &report);
	}

	new_report(report);

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	ret = OK;

	perf_end(_sample_perf);

	return ret;
}
Example #24
0
void
LSM303D::mag_measure()
{
	if (read_reg(ADDR_CTRL_REG7) != _reg7_expected) {
		perf_count(_reg7_resets);
		reset();
		return;
	}

	/* status register and data as read back from the device */
#pragma pack(push, 1)
	struct {
		uint8_t		cmd;
		uint8_t		status;
		int16_t		x;
		int16_t		y;
		int16_t		z;
	} raw_mag_report;
#pragma pack(pop)

	mag_report mag_report;

	/* start the performance counter */
	perf_begin(_mag_sample_perf);

	/* fetch data from the sensor */
	memset(&raw_mag_report, 0, sizeof(raw_mag_report));
	raw_mag_report.cmd = ADDR_STATUS_M | DIR_READ | ADDR_INCREMENT;
	transfer((uint8_t *)&raw_mag_report, (uint8_t *)&raw_mag_report, sizeof(raw_mag_report));

	/*
	 * 1) Scale raw value to SI units using scaling from datasheet.
	 * 2) Subtract static offset (in SI units)
	 * 3) Scale the statically calibrated values with a linear
	 *    dynamically obtained factor
	 *
	 * Note: the static sensor offset is the number the sensor outputs
	 * 	 at a nominally 'zero' input. Therefore the offset has to
	 * 	 be subtracted.
	 *
	 *	 Example: A gyro outputs a value of 74 at zero angular rate
	 *	 	  the offset is 74 from the origin and subtracting
	 *		  74 from all measurements centers them around zero.
	 */


	mag_report.timestamp = hrt_absolute_time();

	mag_report.x_raw = raw_mag_report.x;
	mag_report.y_raw = raw_mag_report.y;
	mag_report.z_raw = raw_mag_report.z;
	mag_report.x = ((mag_report.x_raw * _mag_range_scale) - _mag_scale.x_offset) * _mag_scale.x_scale;
	mag_report.y = ((mag_report.y_raw * _mag_range_scale) - _mag_scale.y_offset) * _mag_scale.y_scale;
	mag_report.z = ((mag_report.z_raw * _mag_range_scale) - _mag_scale.z_offset) * _mag_scale.z_scale;
	mag_report.scaling = _mag_range_scale;
	mag_report.range_ga = (float)_mag_range_ga;

	_mag_reports->force(&mag_report);

	/* XXX please check this poll_notify, is it the right one? */
	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	if (_mag->_mag_topic > 0 && !(_pub_blocked)) {
		/* publish it */
		orb_publish(ORB_ID(sensor_mag), _mag->_mag_topic, &mag_report);
	}

	_mag_read++;

	/* stop the perf counter */
	perf_end(_mag_sample_perf);
}
Example #25
0
int
SF0X::collect()
{
    int	ret;

    perf_begin(_sample_perf);

    /* clear buffer if last read was too long ago */
    uint64_t read_elapsed = hrt_elapsed_time(&_last_read);

    /* the buffer for read chars is buflen minus null termination */
    char readbuf[sizeof(_linebuf)];
    unsigned readlen = sizeof(readbuf) - 1;

    /* read from the sensor (uart buffer) */
    ret = ::read(_fd, &readbuf[0], readlen);

    if (ret < 0) {
        debug("read err: %d", ret);
        perf_count(_comms_errors);
        perf_end(_sample_perf);

        /* only throw an error if we time out */
        if (read_elapsed > (SF0X_CONVERSION_INTERVAL * 2)) {
            return ret;

        } else {
            return -EAGAIN;
        }
    } else if (ret == 0) {
        return -EAGAIN;
    }

    _last_read = hrt_absolute_time();

    float si_units;
    bool valid = false;

    for (int i = 0; i < ret; i++) {
        if (OK == sf0x_parser(readbuf[i], _linebuf, &_linebuf_index, &_parse_state, &si_units)) {
            valid = true;
        }
    }

    if (!valid) {
        return -EAGAIN;
    }

    debug("val (float): %8.4f, raw: %s, valid: %s", (double)si_units, _linebuf, ((valid) ? "OK" : "NO"));

    struct range_finder_report report;

    /* this should be fairly close to the end of the measurement, so the best approximation of the time */
    report.timestamp = hrt_absolute_time();
    report.error_count = perf_event_count(_comms_errors);
    report.distance = si_units;
    report.minimum_distance = get_minimum_distance();
    report.maximum_distance = get_maximum_distance();
    report.valid = valid && (si_units > get_minimum_distance() && si_units < get_maximum_distance() ? 1 : 0);

    /* publish it */
    orb_publish(ORB_ID(sensor_range_finder), _range_finder_topic, &report);

    if (_reports->force(&report)) {
        perf_count(_buffer_overflows);
    }

    /* notify anyone waiting for data */
    poll_notify(POLLIN);

    ret = OK;

    perf_end(_sample_perf);
    return ret;
}
Example #26
0
void
FXOS8700CQ::measure()
{
	/* status register and data as read back from the device */

#pragma pack(push, 1)
	struct {
		uint8_t		cmd[2];
		uint8_t		status;
		int16_t		x;
		int16_t		y;
		int16_t		z;
		int16_t		mx;
		int16_t		my;
		int16_t		mz;
	} raw_accel_mag_report;
#pragma pack(pop)

	accel_report accel_report;

	/* start the performance counter */
	perf_begin(_accel_sample_perf);

	check_registers();

	if (_register_wait != 0) {
		// we are waiting for some good transfers before using
		// the sensor again.
		_register_wait--;
		perf_end(_accel_sample_perf);
		return;
	}

	/* fetch data from the sensor */
	memset(&raw_accel_mag_report, 0, sizeof(raw_accel_mag_report));
	raw_accel_mag_report.cmd[0] = DIR_READ(FXOS8700CQ_DR_STATUS);
	raw_accel_mag_report.cmd[1] = ADDR_7(FXOS8700CQ_DR_STATUS);
	transfer((uint8_t *)&raw_accel_mag_report, (uint8_t *)&raw_accel_mag_report, sizeof(raw_accel_mag_report));

	if (!(raw_accel_mag_report.status & DR_STATUS_ZYXDR)) {
		perf_end(_accel_sample_perf);
		perf_count(_accel_duplicates);
		return;
	}

	/*
	 * 1) Scale raw value to SI units using scaling from datasheet.
	 * 2) Subtract static offset (in SI units)
	 * 3) Scale the statically calibrated values with a linear
	 *    dynamically obtained factor
	 *
	 * Note: the static sensor offset is the number the sensor outputs
	 * 	 at a nominally 'zero' input. Therefore the offset has to
	 * 	 be subtracted.
	 *
	 *	 Example: A gyro outputs a value of 74 at zero angular rate
	 *	 	  the offset is 74 from the origin and subtracting
	 *		  74 from all measurements centers them around zero.
	 */

	accel_report.timestamp = hrt_absolute_time();

	/*
	 * Eight-bit 2’s complement sensor temperature value with 0.96 °C/LSB sensitivity.
	 * Temperature data is only valid between –40 °C and 125 °C. The temperature sensor
	 * output is only valid when M_CTRL_REG1[m_hms] > 0b00. Please note that the
	 * temperature sensor is uncalibrated and its output for a given temperature will vary from
	 * one device to the next
	 */

	write_checked_reg(FXOS8700CQ_M_CTRL_REG1, M_CTRL_REG1_HMS_A | M_CTRL_REG1_OS(7));
	_last_temperature = (read_reg(FXOS8700CQ_TEMP)) * 0.96f;
	write_checked_reg(FXOS8700CQ_M_CTRL_REG1, M_CTRL_REG1_HMS_AM | M_CTRL_REG1_OS(7));

	accel_report.temperature = _last_temperature;

	// report the error count as the sum of the number of bad
	// register reads and bad values. This allows the higher level
	// code to decide if it should use this sensor based on
	// whether it has had failures
	accel_report.error_count = perf_event_count(_bad_registers) + perf_event_count(_bad_values);

	accel_report.x_raw = swap16RightJustify14(raw_accel_mag_report.x);
	accel_report.y_raw = swap16RightJustify14(raw_accel_mag_report.y);
	accel_report.z_raw = swap16RightJustify14(raw_accel_mag_report.z);

	/* Save off the Mag readings todo: revist integrating theses */

	_last_raw_mag_x = swap16(raw_accel_mag_report.mx);
	_last_raw_mag_y = swap16(raw_accel_mag_report.my);
	_last_raw_mag_z = swap16(raw_accel_mag_report.mz);

	float xraw_f = accel_report.x_raw;
	float yraw_f = accel_report.y_raw;
	float zraw_f = accel_report.z_raw;

	// apply user specified rotation
	rotate_3f(_rotation, xraw_f, yraw_f, zraw_f);

	float x_in_new = ((xraw_f * _accel_range_scale) - _accel_scale.x_offset) * _accel_scale.x_scale;
	float y_in_new = ((yraw_f * _accel_range_scale) - _accel_scale.y_offset) * _accel_scale.y_scale;
	float z_in_new = ((zraw_f * _accel_range_scale) - _accel_scale.z_offset) * _accel_scale.z_scale;

	/*
	  we have logs where the accelerometers get stuck at a fixed
	  large value. We want to detect this and mark the sensor as
	  being faulty
	 */
	if (fabsf(_last_accel[0] - x_in_new) < 0.001f &&
	    fabsf(_last_accel[1] - y_in_new) < 0.001f &&
	    fabsf(_last_accel[2] - z_in_new) < 0.001f &&
	    fabsf(x_in_new) > 20 &&
	    fabsf(y_in_new) > 20 &&
	    fabsf(z_in_new) > 20) {
		_constant_accel_count += 1;

	} else {
		_constant_accel_count = 0;
	}

	if (_constant_accel_count > 100) {
		// we've had 100 constant accel readings with large
		// values. The sensor is almost certainly dead. We
		// will raise the error_count so that the top level
		// flight code will know to avoid this sensor, but
		// we'll still give the data so that it can be logged
		// and viewed
		perf_count(_bad_values);
		_constant_accel_count = 0;
	}

	_last_accel[0] = x_in_new;
	_last_accel[1] = y_in_new;
	_last_accel[2] = z_in_new;

	accel_report.x = _accel_filter_x.apply(x_in_new);
	accel_report.y = _accel_filter_y.apply(y_in_new);
	accel_report.z = _accel_filter_z.apply(z_in_new);

	math::Vector<3> aval(x_in_new, y_in_new, z_in_new);
	math::Vector<3> aval_integrated;

	bool accel_notify = _accel_int.put(accel_report.timestamp, aval, aval_integrated, accel_report.integral_dt);
	accel_report.x_integral = aval_integrated(0);
	accel_report.y_integral = aval_integrated(1);
	accel_report.z_integral = aval_integrated(2);

	accel_report.scaling = _accel_range_scale;
	accel_report.range_m_s2 = _accel_range_m_s2;

	/* return device ID */
	accel_report.device_id = _device_id.devid;

	_accel_reports->force(&accel_report);

	/* notify anyone waiting for data */
	if (accel_notify) {
		poll_notify(POLLIN);

		if (!(_pub_blocked)) {
			/* publish it */
			orb_publish(ORB_ID(sensor_accel), _accel_topic, &accel_report);
		}
	}

	_accel_read++;

	/* stop the perf counter */
	perf_end(_accel_sample_perf);
}
Example #27
0
int LidarLiteI2C::collect()
{
	int ret = -EIO;

	/* read from the sensor */
	uint8_t val[2] = {0, 0};

	perf_begin(_sample_perf);

	// read the high and low byte distance registers
	uint8_t distance_reg = LL40LS_DISTHIGH_REG | LL40LS_AUTO_INCREMENT;
	ret = lidar_transfer(&distance_reg, 1, &val[0], sizeof(val));

	// if the transfer failed or if the high bit of distance is
	// set then the distance is invalid
	if (ret < 0 || (val[0] & 0x80)) {
		if (hrt_absolute_time() - _acquire_time_usec > LL40LS_CONVERSION_TIMEOUT) {
			/*
			  NACKs from the sensor are expected when we
			  read before it is ready, so only consider it
			  an error if more than 100ms has elapsed.
			 */
			DEVICE_DEBUG("error reading from sensor: %d", ret);
			perf_count(_comms_errors);

			if (perf_event_count(_comms_errors) % 10 == 0) {
				perf_count(_sensor_resets);
				reset_sensor();
			}
		}

		perf_end(_sample_perf);
		// if we are getting lots of I2C transfer errors try
		// resetting the sensor
		return ret;
	}

	uint16_t distance_cm = (val[0] << 8) | val[1];
	float distance_m = float(distance_cm) * 1e-2f;
	struct distance_sensor_s report;

	if (distance_cm == 0) {
		_zero_counter++;

		if (_zero_counter == 20) {
			/* we have had 20 zeros in a row - reset the
			   sensor. This is a known bad state of the
			   sensor where it returns 16 bits of zero for
			   the distance with a trailing NACK, and
			   keeps doing that even when the target comes
			   into a valid range.
			*/
			_zero_counter = 0;
			perf_end(_sample_perf);
			perf_count(_sensor_zero_resets);
			return reset_sensor();
		}

	} else {
		_zero_counter = 0;
	}

	_last_distance = distance_cm;


	/* this should be fairly close to the end of the measurement, so the best approximation of the time */
	report.timestamp = hrt_absolute_time();
	report.current_distance = distance_m;
	report.min_distance = get_minimum_distance();
	report.max_distance = get_maximum_distance();
	report.covariance = 0.0f;
	/* the sensor is in fact a laser + sonar but there is no enum for this */
	report.type = distance_sensor_s::MAV_DISTANCE_SENSOR_LASER;
	report.orientation = 8;
	/* TODO: set proper ID */
	report.id = 0;

	/* publish it, if we are the primary */
	if (_distance_sensor_topic != nullptr) {
		orb_publish(ORB_ID(distance_sensor), _distance_sensor_topic, &report);
	}

	if (_reports->force(&report)) {
		perf_count(_buffer_overflows);
	}

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	ret = OK;

	perf_end(_sample_perf);
	return ret;
}
Example #28
0
void
FXOS8700CQ::mag_measure()
{
	/* status register and data as read back from the device */

	mag_report mag_report {};

	/* start the performance counter */
	perf_begin(_mag_sample_perf);

	/*
	 * 1) Scale raw value to SI units using scaling from datasheet.
	 * 2) Subtract static offset (in SI units)
	 * 3) Scale the statically calibrated values with a linear
	 *    dynamically obtained factor
	 *
	 * Note: the static sensor offset is the number the sensor outputs
	 * 	 at a nominally 'zero' input. Therefore the offset has to
	 * 	 be subtracted.
	 *
	 *	 Example: A gyro outputs a value of 74 at zero angular rate
	 *	 	  the offset is 74 from the origin and subtracting
	 *		  74 from all measurements centers them around zero.
	 */

	mag_report.timestamp = hrt_absolute_time();
	mag_report.is_external = is_external();

	mag_report.x_raw = _last_raw_mag_x;
	mag_report.y_raw = _last_raw_mag_y;
	mag_report.z_raw = _last_raw_mag_z;

	float xraw_f = mag_report.x_raw;
	float yraw_f = mag_report.y_raw;
	float zraw_f = mag_report.z_raw;

	/* apply user specified rotation */
	rotate_3f(_rotation, xraw_f, yraw_f, zraw_f);

	mag_report.x = ((xraw_f * _mag_range_scale) - _mag_scale.x_offset) * _mag_scale.x_scale;
	mag_report.y = ((yraw_f * _mag_range_scale) - _mag_scale.y_offset) * _mag_scale.y_scale;
	mag_report.z = ((zraw_f * _mag_range_scale) - _mag_scale.z_offset) * _mag_scale.z_scale;
	mag_report.scaling = _mag_range_scale;
	mag_report.range_ga = (float)_mag_range_ga;
	mag_report.error_count = perf_event_count(_bad_registers) + perf_event_count(_bad_values);

	mag_report.temperature = _last_temperature;
	mag_report.device_id = _mag->_device_id.devid;

	_mag_reports->force(&mag_report);

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	if (!(_pub_blocked)) {
		/* publish it */
		orb_publish(ORB_ID(sensor_mag), _mag->_mag_topic, &mag_report);
	}

	_mag_read++;

	/* stop the perf counter */
	perf_end(_mag_sample_perf);
}
int
PX4FLOW::collect()
{
	int	ret = -EIO;

	/* read from the sensor */
	uint8_t val[22] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};

	perf_begin(_sample_perf);

	ret = transfer(nullptr, 0, &val[0], 22);

	if (ret < 0) {
		log("error reading from sensor: %d", ret);
		perf_count(_comms_errors);
		perf_end(_sample_perf);
		return ret;
	}

//	f.frame_count = val[1] << 8 | val[0];
//	f.pixel_flow_x_sum= val[3] << 8 | val[2];
//	f.pixel_flow_y_sum= val[5] << 8 | val[4];
//	f.flow_comp_m_x= val[7] << 8 | val[6];
//	f.flow_comp_m_y= val[9] << 8 | val[8];
//	f.qual= val[11] << 8 | val[10];
//	f.gyro_x_rate= val[13] << 8 | val[12];
//	f.gyro_y_rate= val[15] << 8 | val[14];
//	f.gyro_z_rate= val[17] << 8 | val[16];
//	f.gyro_range= val[18];
//	f.sonar_timestamp= val[19];
//	f.ground_distance= val[21] << 8 | val[20];

	int16_t flowcx = val[7] << 8 | val[6];
	int16_t flowcy = val[9] << 8 | val[8];
	int16_t gdist = val[21] << 8 | val[20];

	struct optical_flow_s report;
	report.flow_comp_x_m = float(flowcx) / 1000.0f;
	report.flow_comp_y_m = float(flowcy) / 1000.0f;
	report.flow_raw_x = val[3] << 8 | val[2];
	report.flow_raw_y = val[5] << 8 | val[4];
	report.ground_distance_m = float(gdist) / 1000.0f;
	report.quality =  val[10];
	report.sensor_id = 0;
	report.timestamp = hrt_absolute_time();


	/* publish it */
	orb_publish(ORB_ID(optical_flow), _px4flow_topic, &report);

	/* post a report to the ring */
	if (_reports->force(&report)) {
		perf_count(_buffer_overflows);
	}

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	ret = OK;

	perf_end(_sample_perf);
	return ret;
}
Example #30
0
int
MEASAirspeed::collect()
{
	int	ret = -EIO;

	/* read from the sensor */
	uint8_t val[4] = {0, 0, 0, 0};


	perf_begin(_sample_perf);

	ret = transfer(nullptr, 0, &val[0], 4);

	if (ret < 0) {
                perf_count(_comms_errors);
                perf_end(_sample_perf);
		return ret;
	}

	uint8_t status = val[0] & 0xC0;

	if (status == 2) {
		log("err: stale data");
                perf_count(_comms_errors);
                perf_end(_sample_perf);
		return ret;
	} else if (status == 3) {
		log("err: fault");
                perf_count(_comms_errors);
                perf_end(_sample_perf);
		return ret;                
	}

	//uint16_t diff_pres_pa = (val[1]) | ((val[0] & ~(0xC0)) << 8);
	uint16_t temp = (val[3] & 0xE0) << 8 | val[2];

	// XXX leaving this in until new calculation method has been cross-checked
	//diff_pres_pa = abs(diff_pres_pa - (16384 / 2.0f));
	//diff_pres_pa -= _diff_pres_offset;
	int16_t dp_raw = 0, dT_raw = 0;
	dp_raw = (val[0] << 8) + val[1];
	dp_raw = 0x3FFF & dp_raw; //mask the used bits
	dT_raw = (val[2] << 8) + val[3];
	dT_raw = (0xFFE0 & dT_raw) >> 5;
	float temperature = ((200 * dT_raw) / 2047) - 50;

	// XXX we may want to smooth out the readings to remove noise.

	// Calculate differential pressure. As its centered around 8000
	// and can go positive or negative, enforce absolute value
//	uint16_t diff_press_pa = abs(dp_raw - (16384 / 2.0f));
	const float P_min = -1.0f;
	const float P_max = 1.0f;
	float diff_press_pa = math::max(0.0f, fabsf( ( ((float)dp_raw - 0.1f*16383.0f) * (P_max-P_min)/(0.8f*16383.0f) + P_min) * 6894.8f)   - _diff_pres_offset);

	struct differential_pressure_s report;

	// Track maximum differential pressure measured (so we can work out top speed).
	if (diff_press_pa > _max_differential_pressure_pa) {
	    _max_differential_pressure_pa = diff_press_pa;
	}

	report.timestamp = hrt_absolute_time();
        report.error_count = perf_event_count(_comms_errors);
	report.temperature = temperature;
	report.differential_pressure_pa = diff_press_pa;
	report.voltage = 0;
	report.max_differential_pressure_pa = _max_differential_pressure_pa;

	/* announce the airspeed if needed, just publish else */
	orb_publish(ORB_ID(differential_pressure), _airspeed_pub, &report);

	new_report(report);

	/* notify anyone waiting for data */
	poll_notify(POLLIN);

	ret = OK;

	perf_end(_sample_perf);

	return ret;
}