From 290ca1f9bf973a9ef957cb413930f7aac06054e4 Mon Sep 17 00:00:00 2001 From: Lorenz Meier Date: Wed, 10 Jul 2013 21:45:59 +0200 Subject: Reworked airspeed driver to keep most of it abstract --- src/drivers/meas_airspeed/meas_airspeed.cpp | 482 ++++++++++++++++++++++++++++ src/drivers/meas_airspeed/module.mk | 41 +++ 2 files changed, 523 insertions(+) create mode 100644 src/drivers/meas_airspeed/meas_airspeed.cpp create mode 100644 src/drivers/meas_airspeed/module.mk (limited to 'src/drivers/meas_airspeed') diff --git a/src/drivers/meas_airspeed/meas_airspeed.cpp b/src/drivers/meas_airspeed/meas_airspeed.cpp new file mode 100644 index 000000000..4fa02a20b --- /dev/null +++ b/src/drivers/meas_airspeed/meas_airspeed.cpp @@ -0,0 +1,482 @@ +/**************************************************************************** + * + * Copyright (C) 2013 PX4 Development Team. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * 3. Neither the name PX4 nor the names of its contributors may be + * used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + ****************************************************************************/ + +/** + * @file meas_airspeed.cpp + * @author Lorenz Meier + * @author Simon Wilks + * + * Driver for the MEAS Spec series connected via I2C. + */ + +#include + +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include + +#include +#include +#include +#include + +#include +#include + +#include +#include +#include + +#include + +/* Default I2C bus */ +#define PX4_I2C_BUS_DEFAULT PX4_I2C_BUS_EXPANSION + +/* I2C bus address */ +#define I2C_ADDRESS 0x75 /* 7-bit address. 8-bit address is 0xEA */ + +/* Register address */ +#define READ_CMD 0x07 /* Read the data */ + +/** + * The Eagle Tree Airspeed V3 cannot provide accurate reading below speeds of 15km/h. + * You can set this value to 12 if you want a zero reading below 15km/h. + */ +#define MIN_ACCURATE_DIFF_PRES_PA 0 + +/* Measurement rate is 100Hz */ +#define CONVERSION_INTERVAL (1000000 / 100) /* microseconds */ + +class MEASAirspeed : public Airspeed +{ +public: + MEASAirspeed(int bus, int address = I2C_ADDRESS); + virtual ~MEASAirspeed(); + +protected: + + /** + * Perform a poll cycle; collect from the previous measurement + * and start a new one. + */ + virtual void cycle(); + virtual int measure(); + virtual int collect(); + +}; + +/* + * Driver 'main' command. + */ +extern "C" __EXPORT int meas_airspeed_main(int argc, char *argv[]); + +MEASAirspeed::MEASAirspeed(int bus, int address) : Airspeed(bus, address, + CONVERSION_INTERVAL) +{ + +} + +int +MEASAirspeed::measure() +{ + int ret; + + /* + * Send the command to begin a measurement. + */ + uint8_t cmd = READ_CMD; + ret = transfer(&cmd, 1, nullptr, 0); + + if (OK != ret) { + perf_count(_comms_errors); + log("i2c::transfer returned %d", ret); + return ret; + } + + ret = OK; + + return ret; +} + +int +MEASAirspeed::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) { + log("error reading from sensor: %d", ret); + return ret; + } + + uint16_t diff_pres_pa = val[1] << 8 | val[0]; + + if (diff_pres_pa < _diff_pres_offset + MIN_ACCURATE_DIFF_PRES_PA) { + diff_pres_pa = 0; + + } else { + diff_pres_pa -= _diff_pres_offset; + } + + // XXX we may want to smooth out the readings to remove noise. + + _reports[_next_report].timestamp = hrt_absolute_time(); + _reports[_next_report].differential_pressure_pa = diff_pres_pa; + + // Track maximum differential pressure measured (so we can work out top speed). + if (diff_pres_pa > _reports[_next_report].max_differential_pressure_pa) { + _reports[_next_report].max_differential_pressure_pa = diff_pres_pa; + } + + /* announce the airspeed if needed, just publish else */ + orb_publish(ORB_ID(differential_pressure), _airspeed_pub, &_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; + + perf_end(_sample_perf); + + return ret; +} + +void +MEASAirspeed::cycle() +{ + /* collection phase? */ + if (_collect_phase) { + + /* perform collection */ + if (OK != collect()) { + log("collection error"); + /* restart the measurement state machine */ + start(); + return; + } + + /* next phase is measurement */ + _collect_phase = false; + + /* + * Is there a collect->measure gap? + */ + if (_measure_ticks > USEC2TICK(CONVERSION_INTERVAL)) { + + /* schedule a fresh cycle call when we are ready to measure again */ + work_queue(HPWORK, + &_work, + (worker_t)&Airspeed::cycle_trampoline, + this, + _measure_ticks - USEC2TICK(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)&Airspeed::cycle_trampoline, + this, + USEC2TICK(CONVERSION_INTERVAL)); +} + +/** + * Local functions in support of the shell command. + */ +namespace meas_airspeed +{ + +/* oddly, ERROR is not defined for c++ */ +#ifdef ERROR +# undef ERROR +#endif +const int ERROR = -1; + +MEASAirspeed *g_dev; + +void start(int i2c_bus); +void stop(); +void test(); +void reset(); +void info(); + +/** + * Start the driver. + */ +void +start(int i2c_bus) +{ + int fd; + + if (g_dev != nullptr) + errx(1, "already started"); + + /* create the driver */ + g_dev = new MEASAirspeed(i2c_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(AIRSPEED_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"); +} + +/** + * Stop the driver + */ +void +stop() +{ + if (g_dev != nullptr) { + delete g_dev; + g_dev = nullptr; + + } else { + errx(1, "driver not running"); + } + + exit(0); +} + +/** + * 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 differential_pressure_s report; + ssize_t sz; + int ret; + + int fd = open(AIRSPEED_DEVICE_PATH, O_RDONLY); + + if (fd < 0) + err(1, "%s open failed (try 'meas_airspeed start' if the driver is not running", AIRSPEED_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("diff pressure: %d pa", report.differential_pressure_pa); + + /* 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("diff pressure: %d pa", report.differential_pressure_pa); + } + + errx(0, "PASS"); +} + +/** + * Reset the driver. + */ +void +reset() +{ + int fd = open(AIRSPEED_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); +} + +} // namespace + + +static void +meas_airspeed_usage() +{ + warnx("usage: meas_airspeed command [options]"); + warnx("options:"); + warnx("\t-b --bus i2cbus (%d)", PX4_I2C_BUS_DEFAULT); + warnx("command:"); + warnx("\tstart|stop|reset|test|info"); +} + +int +meas_airspeed_main(int argc, char *argv[]) +{ + int i2c_bus = PX4_I2C_BUS_DEFAULT; + + int i; + + for (i = 1; i < argc; i++) { + if (strcmp(argv[i], "-b") == 0 || strcmp(argv[i], "--bus") == 0) { + if (argc > i + 1) { + i2c_bus = atoi(argv[i + 1]); + } + } + } + + /* + * Start/load the driver. + */ + if (!strcmp(argv[1], "start")) + meas_airspeed::start(i2c_bus); + + /* + * Stop the driver + */ + if (!strcmp(argv[1], "stop")) + meas_airspeed::stop(); + + /* + * Test the driver/device. + */ + if (!strcmp(argv[1], "test")) + meas_airspeed::test(); + + /* + * Reset the driver. + */ + if (!strcmp(argv[1], "reset")) + meas_airspeed::reset(); + + /* + * Print driver information. + */ + if (!strcmp(argv[1], "info") || !strcmp(argv[1], "status")) + meas_airspeed::info(); + + meas_airspeed_usage(); + exit(0); +} diff --git a/src/drivers/meas_airspeed/module.mk b/src/drivers/meas_airspeed/module.mk new file mode 100644 index 000000000..ddcd54351 --- /dev/null +++ b/src/drivers/meas_airspeed/module.mk @@ -0,0 +1,41 @@ +############################################################################ +# +# Copyright (c) 2013 PX4 Development Team. All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions +# are met: +# +# 1. Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# 2. Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in +# the documentation and/or other materials provided with the +# distribution. +# 3. Neither the name PX4 nor the names of its contributors may be +# used to endorse or promote products derived from this software +# without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS +# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE +# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, +# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, +# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS +# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED +# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN +# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +# POSSIBILITY OF SUCH DAMAGE. +# +############################################################################ + +# +# Makefile to build the MEAS Spec airspeed sensor driver. +# + +MODULE_COMMAND = meas_airspeed +MODULE_STACKSIZE = 1024 + +SRCS = meas_airspeed.cpp -- cgit v1.2.3