1 files changed, 520 insertions, 0 deletions
diff --git a/src/drivers/meas_airspeed/meas_airspeed.cpp b/src/drivers/meas_airspeed/meas_airspeed.cpp
new file mode 100644
index 000000000..05ae21c1f
--- /dev/null
+++ b/src/drivers/meas_airspeed/meas_airspeed.cpp
@@ -0,0 +1,520 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2013, 2014 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 Sarthak Kaingade
+ * @author Simon Wilks
+ * @author Thomas Gubler
+ *
+ * Driver for the MEAS Spec series connected via I2C.
+ *
+ * Supported sensors:
+ *
+ *    - MS4525DO (http://www.meas-spec.com/downloads/MS4525DO.pdf)
+ *    - untested: MS5525DSO (http://www.meas-spec.com/downloads/MS5525DSO.pdf)
+ *
+ * Interface application notes:
+ *
+ *    - Interfacing to MEAS Digital Pressure Modules (http://www.meas-spec.com/downloads/Interfacing_to_MEAS_Digital_Pressure_Modules.pdf)
+ */
+
+#include <nuttx/config.h>
+
+#include <drivers/device/i2c.h>
+
+#include <sys/types.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <semaphore.h>
+#include <string.h>
+#include <fcntl.h>
+#include <poll.h>
+#include <errno.h>
+#include <stdio.h>
+#include <math.h>
+#include <unistd.h>
+
+#include <nuttx/arch.h>
+#include <nuttx/wqueue.h>
+#include <nuttx/clock.h>
+
+#include <board_config.h>
+
+#include <systemlib/airspeed.h>
+#include <systemlib/err.h>
+#include <systemlib/param/param.h>
+#include <systemlib/perf_counter.h>
+
+#include <drivers/drv_airspeed.h>
+#include <drivers/drv_hrt.h>
+
+#include <uORB/uORB.h>
+#include <uORB/topics/differential_pressure.h>
+#include <uORB/topics/subsystem_info.h>
+
+#include <drivers/airspeed/airspeed.h>
+
+/* I2C bus address is 1010001x */
+#define I2C_ADDRESS_MS4525DO	0x28	//0x51 /* 7-bit address. */
+/* The MS5525DSO address is 111011Cx, where C is the complementary value of the pin CSB */
+#define I2C_ADDRESS_MS5525DSO	0x77	//0x77/* 7-bit address, addr. pin pulled low */
+
+/* Register address */
+#define ADDR_READ_MR			0x00	/* write to this address to start conversion */
+
+/* Measurement rate is 100Hz */
+#define CONVERSION_INTERVAL	(1000000 / 100)	/* microseconds */
+
+class MEASAirspeed : public Airspeed
+{
+public:
+	MEASAirspeed(int bus, int address = I2C_ADDRESS_MS4525DO);
+
+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 = 0;
+	ret = transfer(&cmd, 1, nullptr, 0);
+
+	if (OK != ret) {
+		perf_count(_comms_errors);
+	}
+
+	return ret;
+}
+
+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;                
+	}
+
+	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 * dT_raw) / 2047) - 50;
+
+	/* calculate differential pressure. As its centered around 8000
+	 * and can go positive or negative, enforce absolute value
+	*/
+	const float P_min = -1.0f;
+	const float P_max = 1.0f;
+	float diff_press_pa = fabsf( ( ((float)dp_raw - 0.1f*16383.0f) * (P_max-P_min)/(0.8f*16383.0f) + P_min) * 6894.8f) - _diff_pres_offset;
+        if (diff_press_pa < 0.0f)
+            diff_press_pa = 0.0f;
+
+	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;
+
+	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
+MEASAirspeed::cycle()
+{
+	/* collection phase? */
+	if (_collect_phase) {
+
+		/* perform collection */
+		if (OK != collect()) {
+			/* 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 = nullptr;
+
+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, try the MS4525DO first */
+	g_dev = new MEASAirspeed(i2c_bus, I2C_ADDRESS_MS4525DO);
+
+	/* check if the MS4525DO was instantiated */
+	if (g_dev == nullptr)
+		goto fail;
+
+	/* try the MS5525DSO next if init fails */
+	if (OK != g_dev->Airspeed::init()) {
+		delete g_dev;
+		g_dev = new MEASAirspeed(i2c_bus, I2C_ADDRESS_MS5525DSO);
+
+		/* check if the MS5525DSO was instantiated */
+		if (g_dev == nullptr)
+			goto fail;
+
+		/* both versions failed if the init for the MS5525DSO fails, give up */
+		if (OK != g_dev->Airspeed::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", (double)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);
+		warnx("temperature: %d C (0x%02x)", (int)report.temperature, (unsigned) report.temperature);
+	}
+
+	/* reset the sensor polling to its default rate */
+	if (OK != ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_DEFAULT))
+		errx(1, "failed to set default rate");
+
+	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);
+}