forked from Archive/PX4-Autopilot
1183 lines
27 KiB
C++
1183 lines
27 KiB
C++
/****************************************************************************
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*
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* Copyright (C) 2012 PX4 Development Team. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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* 3. Neither the name PX4 nor the names of its contributors may be
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* used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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****************************************************************************/
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/**
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* @file ms5611.cpp
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* Driver for the MS5611 barometric pressure sensor connected via I2C.
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*/
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#include <nuttx/config.h>
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#include <drivers/device/i2c.h>
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#include <sys/types.h>
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#include <stdint.h>
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#include <stdbool.h>
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#include <stdlib.h>
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#include <semaphore.h>
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#include <string.h>
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#include <fcntl.h>
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#include <poll.h>
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#include <errno.h>
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#include <stdio.h>
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#include <math.h>
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#include <unistd.h>
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#include <nuttx/arch.h>
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#include <nuttx/wqueue.h>
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#include <nuttx/clock.h>
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#include <arch/board/board.h>
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#include <drivers/drv_hrt.h>
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#include <systemlib/perf_counter.h>
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#include <systemlib/err.h>
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#include <drivers/drv_baro.h>
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/* oddly, ERROR is not defined for c++ */
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#ifdef ERROR
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# undef ERROR
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#endif
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static const int ERROR = -1;
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#ifndef CONFIG_SCHED_WORKQUEUE
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# error This requires CONFIG_SCHED_WORKQUEUE.
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#endif
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/**
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* Calibration PROM as reported by the device.
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*/
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#pragma pack(push,1)
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struct ms5611_prom_s {
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uint16_t factory_setup;
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uint16_t c1_pressure_sens;
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uint16_t c2_pressure_offset;
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uint16_t c3_temp_coeff_pres_sens;
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uint16_t c4_temp_coeff_pres_offset;
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uint16_t c5_reference_temp;
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uint16_t c6_temp_coeff_temp;
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uint16_t serial_and_crc;
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};
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/**
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* Grody hack for crc4()
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*/
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union ms5611_prom_u {
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uint16_t c[8];
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struct ms5611_prom_s s;
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};
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#pragma pack(pop)
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class MS5611 : public device::I2C
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{
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public:
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MS5611(int bus);
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~MS5611();
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virtual int init();
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virtual ssize_t read(struct file *filp, char *buffer, size_t buflen);
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virtual int ioctl(struct file *filp, int cmd, unsigned long arg);
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/**
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* Diagnostics - print some basic information about the driver.
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*/
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void print_info();
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protected:
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virtual int probe();
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private:
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union ms5611_prom_u _prom;
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struct work_s _work;
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unsigned _measure_ticks;
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unsigned _num_reports;
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volatile unsigned _next_report;
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volatile unsigned _oldest_report;
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struct baro_report *_reports;
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bool _collect_phase;
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unsigned _measure_phase;
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/* intermediate temperature values per MS5611 datasheet */
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int32_t _TEMP;
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int64_t _OFF;
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int64_t _SENS;
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/* altitude conversion calibration */
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unsigned _msl_pressure; /* in kPa */
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orb_advert_t _baro_topic;
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perf_counter_t _sample_perf;
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perf_counter_t _comms_errors;
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perf_counter_t _buffer_overflows;
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/**
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* Test whether the device supported by the driver is present at a
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* specific address.
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*
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* @param address The I2C bus address to probe.
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* @return True if the device is present.
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*/
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int probe_address(uint8_t address);
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/**
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* Initialise the automatic measurement state machine and start it.
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*
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* @note This function is called at open and error time. It might make sense
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* to make it more aggressive about resetting the bus in case of errors.
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*/
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void start();
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/**
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* Stop the automatic measurement state machine.
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*/
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void stop();
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/**
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* Perform a poll cycle; collect from the previous measurement
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* and start a new one.
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*
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* This is the heart of the measurement state machine. This function
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* alternately starts a measurement, or collects the data from the
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* previous measurement.
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*
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* When the interval between measurements is greater than the minimum
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* measurement interval, a gap is inserted between collection
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* and measurement to provide the most recent measurement possible
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* at the next interval.
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*/
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void cycle();
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/**
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* Static trampoline from the workq context; because we don't have a
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* generic workq wrapper yet.
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*
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* @param arg Instance pointer for the driver that is polling.
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*/
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static void cycle_trampoline(void *arg);
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/**
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* Issue a measurement command for the current state.
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*
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* @return OK if the measurement command was successful.
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*/
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int measure();
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/**
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* Collect the result of the most recent measurement.
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*/
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int collect();
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/**
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* Send a reset command to the MS5611.
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*
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* This is required after any bus reset.
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*/
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int cmd_reset();
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/**
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* Read the MS5611 PROM
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*
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* @return OK if the PROM reads successfully.
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*/
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int read_prom();
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/**
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* PROM CRC routine ported from MS5611 application note
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*
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* @param n_prom Pointer to words read from PROM.
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* @return True if the CRC matches.
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*/
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bool crc4(uint16_t *n_prom);
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};
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/* helper macro for handling report buffer indices */
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#define INCREMENT(_x, _lim) do { _x++; if (_x >= _lim) _x = 0; } while(0)
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/* helper macro for arithmetic - returns the square of the argument */
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#define POW2(_x) ((_x) * (_x))
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/*
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* MS5611 internal constants and data structures.
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*/
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/* internal conversion time: 9.17 ms, so should not be read at rates higher than 100 Hz */
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#define MS5611_CONVERSION_INTERVAL 10000 /* microseconds */
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#define MS5611_MEASUREMENT_RATIO 3 /* pressure measurements per temperature measurement */
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#define MS5611_BUS PX4_I2C_BUS_ONBOARD
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#define MS5611_ADDRESS_1 PX4_I2C_OBDEV_MS5611 /* address select pins pulled high (PX4FMU series v1.6+) */
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#define MS5611_ADDRESS_2 0x77 /* address select pins pulled low (PX4FMU prototypes) */
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#define ADDR_RESET_CMD 0x1E /* write to this address to reset chip */
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#define ADDR_CMD_CONVERT_D1 0x48 /* write to this address to start temperature conversion */
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#define ADDR_CMD_CONVERT_D2 0x58 /* write to this address to start pressure conversion */
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#define ADDR_DATA 0x00 /* address of 3 bytes / 32bit pressure data */
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#define ADDR_PROM_SETUP 0xA0 /* address of 8x 2 bytes factory and calibration data */
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#define ADDR_PROM_C1 0xA2 /* address of 6x 2 bytes calibration data */
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/*
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* Driver 'main' command.
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*/
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extern "C" __EXPORT int ms5611_main(int argc, char *argv[]);
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MS5611::MS5611(int bus) :
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I2C("MS5611", BARO_DEVICE_PATH, bus, 0, 400000),
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_measure_ticks(0),
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_num_reports(0),
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_next_report(0),
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_oldest_report(0),
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_reports(nullptr),
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_collect_phase(false),
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_measure_phase(0),
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_TEMP(0),
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_OFF(0),
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_SENS(0),
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_msl_pressure(101325),
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_baro_topic(-1),
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_sample_perf(perf_alloc(PC_ELAPSED, "ms5611_read")),
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_comms_errors(perf_alloc(PC_COUNT, "ms5611_comms_errors")),
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_buffer_overflows(perf_alloc(PC_COUNT, "ms5611_buffer_overflows"))
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{
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// enable debug() calls
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_debug_enabled = true;
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// work_cancel in the dtor will explode if we don't do this...
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memset(&_work, 0, sizeof(_work));
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}
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MS5611::~MS5611()
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{
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/* make sure we are truly inactive */
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stop();
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/* free any existing reports */
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if (_reports != nullptr)
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delete[] _reports;
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}
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int
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MS5611::init()
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{
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int ret = ERROR;
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/* do I2C init (and probe) first */
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if (I2C::init() != OK)
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goto out;
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/* allocate basic report buffers */
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_num_reports = 2;
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_reports = new struct baro_report[_num_reports];
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if (_reports == nullptr)
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goto out;
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_oldest_report = _next_report = 0;
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/* get a publish handle on the baro topic */
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memset(&_reports[0], 0, sizeof(_reports[0]));
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_baro_topic = orb_advertise(ORB_ID(sensor_baro), &_reports[0]);
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if (_baro_topic < 0)
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debug("failed to create sensor_baro object");
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ret = OK;
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out:
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return ret;
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}
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int
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MS5611::probe()
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{
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_retries = 10;
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if ((OK == probe_address(MS5611_ADDRESS_1)) ||
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(OK == probe_address(MS5611_ADDRESS_2))) {
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_retries = 1;
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return OK;
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}
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return -EIO;
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}
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int
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MS5611::probe_address(uint8_t address)
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{
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/* select the address we are going to try */
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set_address(address);
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/* send reset command */
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if (OK != cmd_reset())
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return -EIO;
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/* read PROM */
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if (OK != read_prom())
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return -EIO;
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return OK;
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}
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ssize_t
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MS5611::read(struct file *filp, char *buffer, size_t buflen)
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{
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unsigned count = buflen / sizeof(struct baro_report);
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int ret = 0;
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/* buffer must be large enough */
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if (count < 1)
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return -ENOSPC;
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/* if automatic measurement is enabled */
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if (_measure_ticks > 0) {
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/*
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* While there is space in the caller's buffer, and reports, copy them.
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* Note that we may be pre-empted by the workq thread while we are doing this;
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* we are careful to avoid racing with them.
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*/
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while (count--) {
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if (_oldest_report != _next_report) {
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memcpy(buffer, _reports + _oldest_report, sizeof(*_reports));
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ret += sizeof(_reports[0]);
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INCREMENT(_oldest_report, _num_reports);
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}
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}
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/* if there was no data, warn the caller */
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return ret ? ret : -EAGAIN;
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}
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/* manual measurement - run one conversion */
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/* XXX really it'd be nice to lock against other readers here */
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do {
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_measure_phase = 0;
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_oldest_report = _next_report = 0;
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/* do temperature first */
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if (OK != measure()) {
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ret = -EIO;
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break;
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}
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usleep(MS5611_CONVERSION_INTERVAL);
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if (OK != collect()) {
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ret = -EIO;
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break;
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}
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/* now do a pressure measurement */
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if (OK != measure()) {
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ret = -EIO;
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break;
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}
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usleep(MS5611_CONVERSION_INTERVAL);
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if (OK != collect()) {
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ret = -EIO;
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break;
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}
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/* state machine will have generated a report, copy it out */
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memcpy(buffer, _reports, sizeof(*_reports));
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ret = sizeof(*_reports);
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} while (0);
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return ret;
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}
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int
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MS5611::ioctl(struct file *filp, int cmd, unsigned long arg)
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{
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switch (cmd) {
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case SENSORIOCSPOLLRATE: {
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switch (arg) {
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/* switching to manual polling */
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case SENSOR_POLLRATE_MANUAL:
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stop();
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_measure_ticks = 0;
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return OK;
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/* external signalling not supported */
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case SENSOR_POLLRATE_EXTERNAL:
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/* zero would be bad */
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case 0:
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return -EINVAL;
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/* set default/max polling rate */
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case SENSOR_POLLRATE_MAX:
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case SENSOR_POLLRATE_DEFAULT: {
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/* do we need to start internal polling? */
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bool want_start = (_measure_ticks == 0);
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/* set interval for next measurement to minimum legal value */
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_measure_ticks = USEC2TICK(MS5611_CONVERSION_INTERVAL);
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/* if we need to start the poll state machine, do it */
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if (want_start)
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start();
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return OK;
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}
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/* adjust to a legal polling interval in Hz */
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default: {
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/* do we need to start internal polling? */
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bool want_start = (_measure_ticks == 0);
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/* convert hz to tick interval via microseconds */
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unsigned ticks = USEC2TICK(1000000 / arg);
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/* check against maximum rate */
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if (ticks < USEC2TICK(MS5611_CONVERSION_INTERVAL))
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return -EINVAL;
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/* update interval for next measurement */
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_measure_ticks = ticks;
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/* if we need to start the poll state machine, do it */
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if (want_start)
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start();
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return OK;
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}
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}
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}
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case SENSORIOCGPOLLRATE:
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if (_measure_ticks == 0)
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return SENSOR_POLLRATE_MANUAL;
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return (1000 / _measure_ticks);
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case SENSORIOCSQUEUEDEPTH: {
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/* add one to account for the sentinel in the ring */
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arg++;
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/* lower bound is mandatory, upper bound is a sanity check */
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if ((arg < 2) || (arg > 100))
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return -EINVAL;
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/* allocate new buffer */
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struct baro_report *buf = new struct baro_report[arg];
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if (nullptr == buf)
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return -ENOMEM;
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/* reset the measurement state machine with the new buffer, free the old */
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stop();
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delete[] _reports;
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_num_reports = arg;
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_reports = buf;
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start();
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return OK;
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}
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case SENSORIOCGQUEUEDEPTH:
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return _num_reports - 1;
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case SENSORIOCRESET:
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/* XXX implement this */
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return -EINVAL;
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case BAROIOCSMSLPRESSURE:
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/* range-check for sanity */
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if ((arg < 80000) || (arg > 120000))
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return -EINVAL;
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_msl_pressure = arg;
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return OK;
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case BAROIOCGMSLPRESSURE:
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return _msl_pressure;
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default:
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break;
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}
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/* give it to the superclass */
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return I2C::ioctl(filp, cmd, arg);
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}
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void
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MS5611::start()
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{
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/* reset the report ring and state machine */
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_collect_phase = false;
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_measure_phase = 0;
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_oldest_report = _next_report = 0;
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/* schedule a cycle to start things */
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work_queue(HPWORK, &_work, (worker_t)&MS5611::cycle_trampoline, this, 1);
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}
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void
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MS5611::stop()
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{
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work_cancel(HPWORK, &_work);
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}
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|
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void
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MS5611::cycle_trampoline(void *arg)
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{
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MS5611 *dev = (MS5611 *)arg;
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dev->cycle();
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}
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|
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void
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MS5611::cycle()
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{
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|
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/* collection phase? */
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if (_collect_phase) {
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|
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/* perform collection */
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if (OK != collect()) {
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log("collection error");
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/* reset the collection state machine and try again */
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start();
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return;
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}
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|
|
/* next phase is measurement */
|
|
_collect_phase = false;
|
|
|
|
/*
|
|
* Is there a collect->measure gap?
|
|
* Don't inject one after temperature measurements, so we can keep
|
|
* doing pressure measurements at something close to the desired rate.
|
|
*/
|
|
if ((_measure_phase != 0) &&
|
|
(_measure_ticks > USEC2TICK(MS5611_CONVERSION_INTERVAL))) {
|
|
|
|
/* schedule a fresh cycle call when we are ready to measure again */
|
|
work_queue(HPWORK,
|
|
&_work,
|
|
(worker_t)&MS5611::cycle_trampoline,
|
|
this,
|
|
_measure_ticks - USEC2TICK(MS5611_CONVERSION_INTERVAL));
|
|
|
|
return;
|
|
}
|
|
}
|
|
|
|
/* measurement phase */
|
|
if (OK != measure())
|
|
log("measure error");
|
|
|
|
/* next phase is collection */
|
|
_collect_phase = true;
|
|
|
|
/* schedule a fresh cycle call when the measurement is done */
|
|
work_queue(HPWORK,
|
|
&_work,
|
|
(worker_t)&MS5611::cycle_trampoline,
|
|
this,
|
|
USEC2TICK(MS5611_CONVERSION_INTERVAL));
|
|
}
|
|
|
|
int
|
|
MS5611::measure()
|
|
{
|
|
int ret;
|
|
|
|
/*
|
|
* In phase zero, request temperature; in other phases, request pressure.
|
|
*/
|
|
uint8_t cmd_data = (_measure_phase == 0) ? ADDR_CMD_CONVERT_D2 : ADDR_CMD_CONVERT_D1;
|
|
|
|
/*
|
|
* Send the command to begin measuring.
|
|
*/
|
|
ret = transfer(&cmd_data, 1, nullptr, 0);
|
|
|
|
if (OK != ret)
|
|
perf_count(_comms_errors);
|
|
|
|
return ret;
|
|
}
|
|
|
|
int
|
|
MS5611::collect()
|
|
{
|
|
uint8_t cmd;
|
|
uint8_t data[3];
|
|
union {
|
|
uint8_t b[4];
|
|
uint32_t w;
|
|
} cvt;
|
|
|
|
/* read the most recent measurement */
|
|
cmd = 0;
|
|
|
|
perf_begin(_sample_perf);
|
|
|
|
/* this should be fairly close to the end of the conversion, so the best approximation of the time */
|
|
_reports[_next_report].timestamp = hrt_absolute_time();
|
|
|
|
if (OK != transfer(&cmd, 1, &data[0], 3)) {
|
|
perf_count(_comms_errors);
|
|
return -EIO;
|
|
}
|
|
|
|
/* fetch the raw value */
|
|
cvt.b[0] = data[2];
|
|
cvt.b[1] = data[1];
|
|
cvt.b[2] = data[0];
|
|
cvt.b[3] = 0;
|
|
uint32_t raw = cvt.w;
|
|
|
|
/* handle a measurement */
|
|
if (_measure_phase == 0) {
|
|
|
|
/* temperature offset (in ADC units) */
|
|
int32_t dT = (int32_t)raw - ((int32_t)_prom.s.c5_reference_temp << 8);
|
|
|
|
/* absolute temperature in centidegrees - note intermediate value is outside 32-bit range */
|
|
_TEMP = 2000 + (int32_t)(((int64_t)dT * _prom.s.c6_temp_coeff_temp) >> 23);
|
|
|
|
/* base sensor scale/offset values */
|
|
_SENS = ((int64_t)_prom.s.c1_pressure_sens << 15) + (((int64_t)_prom.s.c3_temp_coeff_pres_sens * dT) >> 8);
|
|
_OFF = ((int64_t)_prom.s.c2_pressure_offset << 16) + (((int64_t)_prom.s.c4_temp_coeff_pres_offset * dT) >> 7);
|
|
|
|
/* temperature compensation */
|
|
if (_TEMP < 2000) {
|
|
|
|
int32_t T2 = POW2(dT) >> 31;
|
|
|
|
int64_t f = POW2((int64_t)_TEMP - 2000);
|
|
int64_t OFF2 = 5 * f >> 1;
|
|
int64_t SENS2 = 5 * f >> 2;
|
|
|
|
if (_TEMP < -1500) {
|
|
int64_t f2 = POW2(_TEMP + 1500);
|
|
OFF2 += 7 * f2;
|
|
SENS2 += 11 * f2 >> 1;
|
|
}
|
|
|
|
_TEMP -= T2;
|
|
_OFF -= OFF2;
|
|
_SENS -= SENS2;
|
|
}
|
|
|
|
} else {
|
|
|
|
/* pressure calculation, result in Pa */
|
|
int32_t P = (((raw * _SENS) >> 21) - _OFF) >> 15;
|
|
|
|
/* generate a new report */
|
|
_reports[_next_report].temperature = _TEMP / 100.0f;
|
|
_reports[_next_report].pressure = P / 100.0f; /* convert to millibar */
|
|
|
|
/* altitude calculations based on http://www.kansasflyer.org/index.asp?nav=Avi&sec=Alti&tab=Theory&pg=1 */
|
|
|
|
/*
|
|
* PERFORMANCE HINT:
|
|
*
|
|
* The single precision calculation is 50 microseconds faster than the double
|
|
* precision variant. It is however not obvious if double precision is required.
|
|
* Pending more inspection and tests, we'll leave the double precision variant active.
|
|
*
|
|
* Measurements:
|
|
* double precision: ms5611_read: 992 events, 258641us elapsed, min 202us max 305us
|
|
* single precision: ms5611_read: 963 events, 208066us elapsed, min 202us max 241us
|
|
*/
|
|
#if 0/* USE_FLOAT */
|
|
/* tropospheric properties (0-11km) for standard atmosphere */
|
|
const float T1 = 15.0f + 273.15f; /* temperature at base height in Kelvin */
|
|
const float a = -6.5f / 1000f; /* temperature gradient in degrees per metre */
|
|
const float g = 9.80665f; /* gravity constant in m/s/s */
|
|
const float R = 287.05f; /* ideal gas constant in J/kg/K */
|
|
|
|
/* current pressure at MSL in kPa */
|
|
float p1 = _msl_pressure / 1000.0f;
|
|
|
|
/* measured pressure in kPa */
|
|
float p = P / 1000.0f;
|
|
|
|
/*
|
|
* Solve:
|
|
*
|
|
* / -(aR / g) \
|
|
* | (p / p1) . T1 | - T1
|
|
* \ /
|
|
* h = ------------------------------- + h1
|
|
* a
|
|
*/
|
|
_reports[_next_report].altitude = (((powf((p / p1), (-(a * R) / g))) * T1) - T1) / a;
|
|
#else
|
|
/* tropospheric properties (0-11km) for standard atmosphere */
|
|
const double T1 = 15.0 + 273.15; /* temperature at base height in Kelvin */
|
|
const double a = -6.5 / 1000; /* temperature gradient in degrees per metre */
|
|
const double g = 9.80665; /* gravity constant in m/s/s */
|
|
const double R = 287.05; /* ideal gas constant in J/kg/K */
|
|
|
|
/* current pressure at MSL in kPa */
|
|
double p1 = _msl_pressure / 1000.0;
|
|
|
|
/* measured pressure in kPa */
|
|
double p = P / 1000.0;
|
|
|
|
/*
|
|
* Solve:
|
|
*
|
|
* / -(aR / g) \
|
|
* | (p / p1) . T1 | - T1
|
|
* \ /
|
|
* h = ------------------------------- + h1
|
|
* a
|
|
*/
|
|
_reports[_next_report].altitude = (((pow((p / p1), (-(a * R) / g))) * T1) - T1) / a;
|
|
#endif
|
|
/* publish it */
|
|
orb_publish(ORB_ID(sensor_baro), _baro_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);
|
|
}
|
|
|
|
/* update the measurement state machine */
|
|
INCREMENT(_measure_phase, MS5611_MEASUREMENT_RATIO + 1);
|
|
|
|
perf_end(_sample_perf);
|
|
|
|
return OK;
|
|
}
|
|
|
|
int
|
|
MS5611::cmd_reset()
|
|
{
|
|
unsigned old_retrycount = _retries;
|
|
uint8_t cmd = ADDR_RESET_CMD;
|
|
int result;
|
|
|
|
/* bump the retry count */
|
|
_retries = 10;
|
|
result = transfer(&cmd, 1, nullptr, 0);
|
|
_retries = old_retrycount;
|
|
|
|
return result;
|
|
}
|
|
|
|
int
|
|
MS5611::read_prom()
|
|
{
|
|
uint8_t prom_buf[2];
|
|
union {
|
|
uint8_t b[2];
|
|
uint16_t w;
|
|
} cvt;
|
|
|
|
/*
|
|
* Wait for PROM contents to be in the device (2.8 ms) in the case we are
|
|
* called immediately after reset.
|
|
*/
|
|
usleep(3000);
|
|
|
|
/* read and convert PROM words */
|
|
for (int i = 0; i < 8; i++) {
|
|
uint8_t cmd = ADDR_PROM_SETUP + (i * 2);
|
|
|
|
if (OK != transfer(&cmd, 1, &prom_buf[0], 2))
|
|
break;
|
|
|
|
/* assemble 16 bit value and convert from big endian (sensor) to little endian (MCU) */
|
|
cvt.b[0] = prom_buf[1];
|
|
cvt.b[1] = prom_buf[0];
|
|
_prom.c[i] = cvt.w;
|
|
}
|
|
|
|
/* calculate CRC and return success/failure accordingly */
|
|
return crc4(&_prom.c[0]) ? OK : -EIO;
|
|
}
|
|
|
|
bool
|
|
MS5611::crc4(uint16_t *n_prom)
|
|
{
|
|
int16_t cnt;
|
|
uint16_t n_rem;
|
|
uint16_t crc_read;
|
|
uint8_t n_bit;
|
|
|
|
n_rem = 0x00;
|
|
|
|
/* save the read crc */
|
|
crc_read = n_prom[7];
|
|
|
|
/* remove CRC byte */
|
|
n_prom[7] = (0xFF00 & (n_prom[7]));
|
|
|
|
for (cnt = 0; cnt < 16; cnt++) {
|
|
/* uneven bytes */
|
|
if (cnt & 1) {
|
|
n_rem ^= (uint8_t)((n_prom[cnt >> 1]) & 0x00FF);
|
|
|
|
} else {
|
|
n_rem ^= (uint8_t)(n_prom[cnt >> 1] >> 8);
|
|
}
|
|
|
|
for (n_bit = 8; n_bit > 0; n_bit--) {
|
|
if (n_rem & 0x8000) {
|
|
n_rem = (n_rem << 1) ^ 0x3000;
|
|
|
|
} else {
|
|
n_rem = (n_rem << 1);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* final 4 bit remainder is CRC value */
|
|
n_rem = (0x000F & (n_rem >> 12));
|
|
n_prom[7] = crc_read;
|
|
|
|
/* return true if CRCs match */
|
|
return (0x000F & crc_read) == (n_rem ^ 0x00);
|
|
}
|
|
|
|
void
|
|
MS5611::print_info()
|
|
{
|
|
perf_print_counter(_sample_perf);
|
|
perf_print_counter(_comms_errors);
|
|
perf_print_counter(_buffer_overflows);
|
|
printf("poll interval: %u ticks\n", _measure_ticks);
|
|
printf("report queue: %u (%u/%u @ %p)\n",
|
|
_num_reports, _oldest_report, _next_report, _reports);
|
|
printf("TEMP: %d\n", _TEMP);
|
|
printf("SENS: %lld\n", _SENS);
|
|
printf("OFF: %lld\n", _OFF);
|
|
printf("MSL pressure: %10.4f\n", (double)(_msl_pressure / 100.f));
|
|
|
|
printf("factory_setup %u\n", _prom.s.factory_setup);
|
|
printf("c1_pressure_sens %u\n", _prom.s.c1_pressure_sens);
|
|
printf("c2_pressure_offset %u\n", _prom.s.c2_pressure_offset);
|
|
printf("c3_temp_coeff_pres_sens %u\n", _prom.s.c3_temp_coeff_pres_sens);
|
|
printf("c4_temp_coeff_pres_offset %u\n", _prom.s.c4_temp_coeff_pres_offset);
|
|
printf("c5_reference_temp %u\n", _prom.s.c5_reference_temp);
|
|
printf("c6_temp_coeff_temp %u\n", _prom.s.c6_temp_coeff_temp);
|
|
printf("serial_and_crc %u\n", _prom.s.serial_and_crc);
|
|
}
|
|
|
|
/**
|
|
* Local functions in support of the shell command.
|
|
*/
|
|
namespace ms5611
|
|
{
|
|
|
|
MS5611 *g_dev;
|
|
|
|
void start();
|
|
void test();
|
|
void reset();
|
|
void info();
|
|
void calibrate(unsigned altitude);
|
|
|
|
/**
|
|
* Start the driver.
|
|
*/
|
|
void
|
|
start()
|
|
{
|
|
int fd;
|
|
|
|
if (g_dev != nullptr)
|
|
errx(1, "already started");
|
|
|
|
/* create the driver */
|
|
g_dev = new MS5611(MS5611_BUS);
|
|
|
|
if (g_dev == nullptr)
|
|
goto fail;
|
|
|
|
if (OK != g_dev->init())
|
|
goto fail;
|
|
|
|
/* set the poll rate to default, starts automatic data collection */
|
|
fd = open(BARO_DEVICE_PATH, O_RDONLY);
|
|
|
|
if (fd < 0)
|
|
goto fail;
|
|
|
|
if (ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_DEFAULT) < 0)
|
|
goto fail;
|
|
|
|
exit(0);
|
|
|
|
fail:
|
|
|
|
if (g_dev != nullptr) {
|
|
delete g_dev;
|
|
g_dev = nullptr;
|
|
}
|
|
|
|
errx(1, "driver start failed");
|
|
}
|
|
|
|
/**
|
|
* Perform some basic functional tests on the driver;
|
|
* make sure we can collect data from the sensor in polled
|
|
* and automatic modes.
|
|
*/
|
|
void
|
|
test()
|
|
{
|
|
struct baro_report report;
|
|
ssize_t sz;
|
|
int ret;
|
|
|
|
int fd = open(BARO_DEVICE_PATH, O_RDONLY);
|
|
|
|
if (fd < 0)
|
|
err(1, "%s open failed (try 'ms5611 start' if the driver is not running)", BARO_DEVICE_PATH);
|
|
|
|
/* do a simple demand read */
|
|
sz = read(fd, &report, sizeof(report));
|
|
|
|
if (sz != sizeof(report))
|
|
err(1, "immediate read failed");
|
|
|
|
warnx("single read");
|
|
warnx("pressure: %10.4f", (double)report.pressure);
|
|
warnx("altitude: %11.4f", (double)report.altitude);
|
|
warnx("temperature: %8.4f", (double)report.temperature);
|
|
warnx("time: %lld", report.timestamp);
|
|
|
|
/* set the queue depth to 10 */
|
|
if (OK != ioctl(fd, SENSORIOCSQUEUEDEPTH, 10))
|
|
errx(1, "failed to set queue depth");
|
|
|
|
/* start the sensor polling at 2Hz */
|
|
if (OK != ioctl(fd, SENSORIOCSPOLLRATE, 2))
|
|
errx(1, "failed to set 2Hz poll rate");
|
|
|
|
/* read the sensor 5x and report each value */
|
|
for (unsigned i = 0; i < 5; i++) {
|
|
struct pollfd fds;
|
|
|
|
/* wait for data to be ready */
|
|
fds.fd = fd;
|
|
fds.events = POLLIN;
|
|
ret = poll(&fds, 1, 2000);
|
|
|
|
if (ret != 1)
|
|
errx(1, "timed out waiting for sensor data");
|
|
|
|
/* now go get it */
|
|
sz = read(fd, &report, sizeof(report));
|
|
|
|
if (sz != sizeof(report))
|
|
err(1, "periodic read failed");
|
|
|
|
warnx("periodic read %u", i);
|
|
warnx("pressure: %10.4f", (double)report.pressure);
|
|
warnx("altitude: %11.4f", (double)report.altitude);
|
|
warnx("temperature: %8.4f", (double)report.temperature);
|
|
warnx("time: %lld", report.timestamp);
|
|
}
|
|
|
|
errx(0, "PASS");
|
|
}
|
|
|
|
/**
|
|
* Reset the driver.
|
|
*/
|
|
void
|
|
reset()
|
|
{
|
|
int fd = open(BARO_DEVICE_PATH, O_RDONLY);
|
|
|
|
if (fd < 0)
|
|
err(1, "failed ");
|
|
|
|
if (ioctl(fd, SENSORIOCRESET, 0) < 0)
|
|
err(1, "driver reset failed");
|
|
|
|
if (ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_DEFAULT) < 0)
|
|
err(1, "driver poll restart failed");
|
|
|
|
exit(0);
|
|
}
|
|
|
|
/**
|
|
* Print a little info about the driver.
|
|
*/
|
|
void
|
|
info()
|
|
{
|
|
if (g_dev == nullptr)
|
|
errx(1, "driver not running");
|
|
|
|
printf("state @ %p\n", g_dev);
|
|
g_dev->print_info();
|
|
|
|
exit(0);
|
|
}
|
|
|
|
/**
|
|
* Calculate actual MSL pressure given current altitude
|
|
*/
|
|
void
|
|
calibrate(unsigned altitude)
|
|
{
|
|
struct baro_report report;
|
|
float pressure;
|
|
float p1;
|
|
|
|
int fd = open(BARO_DEVICE_PATH, O_RDONLY);
|
|
|
|
if (fd < 0)
|
|
err(1, "%s open failed (try 'ms5611 start' if the driver is not running)", BARO_DEVICE_PATH);
|
|
|
|
/* start the sensor polling at max */
|
|
if (OK != ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_MAX))
|
|
errx(1, "failed to set poll rate");
|
|
|
|
/* average a few measurements */
|
|
pressure = 0.0f;
|
|
|
|
for (unsigned i = 0; i < 20; i++) {
|
|
struct pollfd fds;
|
|
int ret;
|
|
ssize_t sz;
|
|
|
|
/* wait for data to be ready */
|
|
fds.fd = fd;
|
|
fds.events = POLLIN;
|
|
ret = poll(&fds, 1, 1000);
|
|
|
|
if (ret != 1)
|
|
errx(1, "timed out waiting for sensor data");
|
|
|
|
/* now go get it */
|
|
sz = read(fd, &report, sizeof(report));
|
|
|
|
if (sz != sizeof(report))
|
|
err(1, "sensor read failed");
|
|
|
|
pressure += report.pressure;
|
|
}
|
|
|
|
pressure /= 20; /* average */
|
|
pressure /= 10; /* scale from millibar to kPa */
|
|
|
|
/* tropospheric properties (0-11km) for standard atmosphere */
|
|
const float T1 = 15.0 + 273.15; /* temperature at base height in Kelvin */
|
|
const float a = -6.5 / 1000; /* temperature gradient in degrees per metre */
|
|
const float g = 9.80665f; /* gravity constant in m/s/s */
|
|
const float R = 287.05f; /* ideal gas constant in J/kg/K */
|
|
|
|
warnx("averaged pressure %10.4fkPa at %um", pressure, altitude);
|
|
|
|
p1 = pressure * (powf(((T1 + (a * (float)altitude)) / T1), (g / (a * R))));
|
|
|
|
warnx("calculated MSL pressure %10.4fkPa", p1);
|
|
|
|
/* save as integer Pa */
|
|
p1 *= 1000.0f;
|
|
|
|
if (ioctl(fd, BAROIOCSMSLPRESSURE, (unsigned long)p1) != OK)
|
|
err(1, "BAROIOCSMSLPRESSURE");
|
|
|
|
exit(0);
|
|
}
|
|
|
|
} // namespace
|
|
|
|
int
|
|
ms5611_main(int argc, char *argv[])
|
|
{
|
|
/*
|
|
* Start/load the driver.
|
|
*/
|
|
if (!strcmp(argv[1], "start"))
|
|
ms5611::start();
|
|
|
|
/*
|
|
* Test the driver/device.
|
|
*/
|
|
if (!strcmp(argv[1], "test"))
|
|
ms5611::test();
|
|
|
|
/*
|
|
* Reset the driver.
|
|
*/
|
|
if (!strcmp(argv[1], "reset"))
|
|
ms5611::reset();
|
|
|
|
/*
|
|
* Print driver information.
|
|
*/
|
|
if (!strcmp(argv[1], "info"))
|
|
ms5611::info();
|
|
|
|
/*
|
|
* Perform MSL pressure calibration given an altitude in metres
|
|
*/
|
|
if (!strcmp(argv[1], "calibrate")) {
|
|
if (argc < 2)
|
|
errx(1, "missing altitude");
|
|
|
|
long altitude = strtol(argv[2], nullptr, 10);
|
|
|
|
ms5611::calibrate(altitude);
|
|
}
|
|
|
|
errx(1, "unrecognised command, try 'start', 'test', 'reset' or 'info'");
|
|
}
|