Merge remote-tracking branch 'upstream/master' into dev_ros

25 files changed, 1688 insertions, 325 deletions

diff --git a/src/drivers/airspeed/airspeed.cpp b/src/drivers/airspeed/airspeed.cpp
index 3a1e1b7b5..6db6713c4 100644
--- a/src/drivers/airspeed/airspeed.cpp
+++ b/src/drivers/airspeed/airspeed.cpp
@@ -159,13 +159,15 @@ out:
 int
 Airspeed::probe()
 {
-	/* on initial power up the device needs more than one retry
-	   for detection. Once it is running then retries aren't
-	   needed 
+	/* on initial power up the device may need more than one retry
+	   for detection. Once it is running the number of retries can
+	   be reduced
 	*/
 	_retries = 4;
 	int ret = measure();
-	_retries = 0;
+
+        // drop back to 2 retries once initialised
+	_retries = 2;
 	return ret;
 }
 
diff --git a/src/drivers/hmc5883/hmc5883.cpp b/src/drivers/hmc5883/hmc5883.cpp
index 81f767965..d4dbf3778 100644
--- a/src/drivers/hmc5883/hmc5883.cpp
+++ b/src/drivers/hmc5883/hmc5883.cpp
@@ -1349,7 +1349,7 @@ HMC5883	*g_dev_ext = nullptr;
 void	start(int bus, enum Rotation rotation);
 void	test(int bus);
 void	reset(int bus);
-void	info(int bus);
+int	info(int bus);
 int	calibrate(int bus);
 void	usage();
 
@@ -1595,17 +1595,23 @@ reset(int bus)
 /**
  * Print a little info about the driver.
  */
-void
+int
 info(int bus)
 {
-	HMC5883 *g_dev = (bus == PX4_I2C_BUS_ONBOARD?g_dev_int:g_dev_ext);
-	if (g_dev == nullptr)
-		errx(1, "driver not running");
+	int ret = 1;
+
+	HMC5883 *g_dev = (bus == PX4_I2C_BUS_ONBOARD ? g_dev_int : g_dev_ext);
+	if (g_dev == nullptr) {
+		warnx("not running on bus %d", bus);
+	} else {
 
-	printf("state @ %p\n", g_dev);
-	g_dev->print_info();
+		warnx("running on bus: %d (%s)\n", bus, ((PX4_I2C_BUS_ONBOARD) ? "onboard" : "offboard"));
 
-	exit(0);
+		g_dev->print_info();
+		ret = 0;
+	}
+
+	return ret;
 }
 
 void
@@ -1685,8 +1691,21 @@ hmc5883_main(int argc, char *argv[])
 	/*
 	 * Print driver information.
 	 */
-	if (!strcmp(verb, "info") || !strcmp(verb, "status"))
-		hmc5883::info(bus);
+	if (!strcmp(verb, "info") || !strcmp(verb, "status")) {
+		if (bus == -1) {
+			int ret = 0;
+			if (hmc5883::info(PX4_I2C_BUS_ONBOARD)) {
+				ret = 1;
+			}
+
+			if (hmc5883::info(PX4_I2C_BUS_EXPANSION)) {
+				ret = 1;
+			}
+			exit(ret);
+		} else {
+			exit(hmc5883::info(bus));
+		}
+	}
 
 	/*
 	 * Autocalibrate the scaling
diff --git a/src/drivers/px4flow/px4flow.cpp b/src/drivers/px4flow/px4flow.cpp
index 804027b05..09ec4bf96 100644
--- a/src/drivers/px4flow/px4flow.cpp
+++ b/src/drivers/px4flow/px4flow.cpp
@@ -1,6 +1,6 @@
 /****************************************************************************
  *
- *   Copyright (c) 2013 PX4 Development Team. All rights reserved.
+ *   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
@@ -73,15 +73,13 @@
 #include <board_config.h>
 
 /* Configuration Constants */
-#define PX4FLOW_BUS 			PX4_I2C_BUS_EXPANSION
 #define I2C_FLOW_ADDRESS 		0x42 //* 7-bit address. 8-bit address is 0x84
 //range 0x42 - 0x49
 
 /* PX4FLOW Registers addresses */
-#define PX4FLOW_REG	0x00		/* Measure Register */
-
-#define PX4FLOW_CONVERSION_INTERVAL 8000 /* 8ms 125Hz */
+#define PX4FLOW_REG		0x16	/* Measure Register 22*/
 
+#define PX4FLOW_CONVERSION_INTERVAL 20000 //in microseconds! 20000 = 50 Hz 100000 = 10Hz
 /* oddly, ERROR is not defined for c++ */
 #ifdef ERROR
 # undef ERROR
@@ -92,28 +90,42 @@ static const int ERROR = -1;
 # error This requires CONFIG_SCHED_WORKQUEUE.
 #endif
 
-//struct i2c_frame
-//{
-//    uint16_t frame_count;
-//    int16_t pixel_flow_x_sum;
-//    int16_t pixel_flow_y_sum;
-//    int16_t flow_comp_m_x;
-//    int16_t flow_comp_m_y;
-//    int16_t qual;
-//    int16_t gyro_x_rate;
-//    int16_t gyro_y_rate;
-//    int16_t gyro_z_rate;
-//    uint8_t gyro_range;
-//    uint8_t sonar_timestamp;
-//    int16_t ground_distance;
-//};
-//
-//struct i2c_frame f;
-
-class PX4FLOW : public device::I2C
+struct i2c_frame {
+	uint16_t frame_count;
+	int16_t pixel_flow_x_sum;
+	int16_t pixel_flow_y_sum;
+	int16_t flow_comp_m_x;
+	int16_t flow_comp_m_y;
+	int16_t qual;
+	int16_t gyro_x_rate;
+	int16_t gyro_y_rate;
+	int16_t gyro_z_rate;
+	uint8_t gyro_range;
+	uint8_t sonar_timestamp;
+	int16_t ground_distance;
+};
+struct i2c_frame f;
+
+typedef struct i2c_integral_frame {
+	uint16_t frame_count_since_last_readout;
+	int16_t pixel_flow_x_integral;
+	int16_t pixel_flow_y_integral;
+	int16_t gyro_x_rate_integral;
+	int16_t gyro_y_rate_integral;
+	int16_t gyro_z_rate_integral;
+	uint32_t integration_timespan;
+	uint32_t time_since_last_sonar_update;
+	uint16_t ground_distance;
+	int16_t gyro_temperature;
+	uint8_t qual;
+} __attribute__((packed));
+struct i2c_integral_frame f_integral;
+
+
+class PX4FLOW: public device::I2C
 {
 public:
-	PX4FLOW(int bus = PX4FLOW_BUS, int address = I2C_FLOW_ADDRESS);
+	PX4FLOW(int bus, int address = I2C_FLOW_ADDRESS);
 	virtual ~PX4FLOW();
 
 	virtual int 		init();
@@ -122,8 +134,8 @@ public:
 	virtual int			ioctl(struct file *filp, int cmd, unsigned long arg);
 
 	/**
-	* Diagnostics - print some basic information about the driver.
-	*/
+	 * Diagnostics - print some basic information about the driver.
+	 */
 	void				print_info();
 
 protected:
@@ -144,42 +156,41 @@ private:
 	perf_counter_t		_buffer_overflows;
 
 	/**
-	* Test whether the device supported by the driver is present at a
-	* specific address.
-	*
-	* @param address	The I2C bus address to probe.
-	* @return		True if the device is present.
-	*/
+	 * Test whether the device supported by the driver is present at a
+	 * specific address.
+	 *
+	 * @param address	The I2C bus address to probe.
+	 * @return		True if the device is present.
+	 */
 	int					probe_address(uint8_t address);
 
 	/**
-	* Initialise the automatic measurement state machine and start it.
-	*
-	* @note This function is called at open and error time.  It might make sense
-	*       to make it more aggressive about resetting the bus in case of errors.
-	*/
+	 * Initialise the automatic measurement state machine and start it.
+	 *
+	 * @note This function is called at open and error time.  It might make sense
+	 *       to make it more aggressive about resetting the bus in case of errors.
+	 */
 	void				start();
 
 	/**
-	* Stop the automatic measurement state machine.
-	*/
+	 * Stop the automatic measurement state machine.
+	 */
 	void				stop();
 
 	/**
-	* Perform a poll cycle; collect from the previous measurement
-	* and start a new one.
-	*/
+	 * Perform a poll cycle; collect from the previous measurement
+	 * and start a new one.
+	 */
 	void				cycle();
 	int					measure();
 	int					collect();
 	/**
-	* Static trampoline from the workq context; because we don't have a
-	* generic workq wrapper yet.
-	*
-	* @param arg		Instance pointer for the driver that is polling.
-	*/
-	static void		cycle_trampoline(void *arg);
-
+	 * Static trampoline from the workq context; because we don't have a
+	 * generic workq wrapper yet.
+	 *
+	 * @param arg		Instance pointer for the driver that is polling.
+	 */
+	static void			cycle_trampoline(void *arg);
 
 };
 
@@ -189,7 +200,7 @@ private:
 extern "C" __EXPORT int px4flow_main(int argc, char *argv[]);
 
 PX4FLOW::PX4FLOW(int bus, int address) :
-	I2C("PX4FLOW", PX4FLOW_DEVICE_PATH, bus, address, 400000),//400khz
+	I2C("PX4FLOW", PX4FLOW_DEVICE_PATH, bus, address, 400000), //400khz
 	_reports(nullptr),
 	_sensor_ok(false),
 	_measure_ticks(0),
@@ -228,21 +239,12 @@ PX4FLOW::init()
 	}
 
 	/* allocate basic report buffers */
-	_reports = new RingBuffer(2, sizeof(struct optical_flow_s));
+	_reports = new RingBuffer(2, sizeof(optical_flow_s));
 
 	if (_reports == nullptr) {
 		goto out;
 	}
 
-	/* get a publish handle on the px4flow topic */
-	struct optical_flow_s zero_report;
-	memset(&zero_report, 0, sizeof(zero_report));
-	_px4flow_topic = orb_advertise(ORB_ID(optical_flow), &zero_report);
-
-	if (_px4flow_topic < 0) {
-		warnx("failed to create px4flow object. Did you start uOrb?");
-	}
-
 	ret = OK;
 	/* sensor is ok, but we don't really know if it is within range */
 	_sensor_ok = true;
@@ -410,9 +412,6 @@ PX4FLOW::read(struct file *filp, char *buffer, size_t buflen)
 			break;
 		}
 
-		/* wait for it to complete */
-		usleep(PX4FLOW_CONVERSION_INTERVAL);
-
 		/* run the collection phase */
 		if (OK != collect()) {
 			ret = -EIO;
@@ -442,6 +441,7 @@ PX4FLOW::measure()
 
 	if (OK != ret) {
 		perf_count(_comms_errors);
+		debug("i2c::transfer returned %d", ret);
 		return ret;
 	}
 
@@ -453,14 +453,20 @@ PX4FLOW::measure()
 int
 PX4FLOW::collect()
 {
-	int	ret = -EIO;
+	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};
+	uint8_t val[47] = { 0 };
 
 	perf_begin(_sample_perf);
 
-	ret = transfer(nullptr, 0, &val[0], 22);
+	if (PX4FLOW_REG == 0x00) {
+		ret = transfer(nullptr, 0, &val[0], 47); // read 47 bytes (22+25 : frame1 + frame2)
+	}
+
+	if (PX4FLOW_REG == 0x16) {
+		ret = transfer(nullptr, 0, &val[0], 25); // read 25 bytes (only frame2)
+	}
 
 	if (ret < 0) {
 		debug("error reading from sensor: %d", ret);
@@ -469,36 +475,74 @@ PX4FLOW::collect()
 		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];
+	if (PX4FLOW_REG == 0) {
+		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];
+
+		f_integral.frame_count_since_last_readout = val[23] << 8 | val[22];
+		f_integral.pixel_flow_x_integral = val[25] << 8 | val[24];
+		f_integral.pixel_flow_y_integral = val[27] << 8 | val[26];
+		f_integral.gyro_x_rate_integral = val[29] << 8 | val[28];
+		f_integral.gyro_y_rate_integral = val[31] << 8 | val[30];
+		f_integral.gyro_z_rate_integral = val[33] << 8 | val[32];
+		f_integral.integration_timespan = val[37] << 24 | val[36] << 16
+						  | val[35] << 8 | val[34];
+		f_integral.time_since_last_sonar_update = val[41] << 24 | val[40] << 16
+				| val[39] << 8 | val[38];
+		f_integral.ground_distance = val[43] << 8 | val[42];
+		f_integral.gyro_temperature = val[45] << 8 | val[44];
+		f_integral.qual = val[46];
+	}
+
+	if (PX4FLOW_REG == 0x16) {
+		f_integral.frame_count_since_last_readout = val[1] << 8 | val[0];
+		f_integral.pixel_flow_x_integral = val[3] << 8 | val[2];
+		f_integral.pixel_flow_y_integral = val[5] << 8 | val[4];
+		f_integral.gyro_x_rate_integral = val[7] << 8 | val[6];
+		f_integral.gyro_y_rate_integral = val[9] << 8 | val[8];
+		f_integral.gyro_z_rate_integral = val[11] << 8 | val[10];
+		f_integral.integration_timespan = val[15] << 24 | val[14] << 16 | val[13] << 8 | val[12];
+		f_integral.time_since_last_sonar_update = val[19] << 24 | val[18] << 16 | val[17] << 8 | val[16];
+		f_integral.ground_distance = val[21] << 8 | val[20];
+		f_integral.gyro_temperature = val[23] << 8 | val[22];
+		f_integral.qual = val[24];
+	}
 
-	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();
+	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.time_since_last_sonar_update;//microseconds
+	report.gyro_temperature = f_integral.gyro_temperature;//Temperature * 100 in centi-degrees Celsius
+
+	report.sensor_id = 0;
 
+	if (_px4flow_topic < 0) {
+		_px4flow_topic = orb_advertise(ORB_ID(optical_flow), &report);
 
-	/* publish it */
-	orb_publish(ORB_ID(optical_flow), _px4flow_topic, &report);
+	} else {
+		/* publish it */
+		orb_publish(ORB_ID(optical_flow), _px4flow_topic, &report);
+	}
 
 	/* post a report to the ring */
 	if (_reports->force(&report)) {
@@ -558,50 +602,21 @@ PX4FLOW::cycle_trampoline(void *arg)
 void
 PX4FLOW::cycle()
 {
-	/* collection phase? */
-	if (_collect_phase) {
-
-		/* perform collection */
-		if (OK != collect()) {
-			debug("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(PX4FLOW_CONVERSION_INTERVAL)) {
-
-			/* schedule a fresh cycle call when we are ready to measure again */
-			work_queue(HPWORK,
-				   &_work,
-				   (worker_t)&PX4FLOW::cycle_trampoline,
-				   this,
-				   _measure_ticks - USEC2TICK(PX4FLOW_CONVERSION_INTERVAL));
-
-			return;
-		}
-	}
-
-	/* measurement phase */
 	if (OK != measure()) {
 		debug("measure error");
 	}
 
-	/* next phase is collection */
-	_collect_phase = true;
+	/* perform collection */
+	if (OK != collect()) {
+		debug("collection error");
+		/* restart the measurement state machine */
+		start();
+		return;
+	}
+
+	work_queue(HPWORK, &_work, (worker_t)&PX4FLOW::cycle_trampoline, this,
+		   _measure_ticks);
 
-	/* schedule a fresh cycle call when the measurement is done */
-	work_queue(HPWORK,
-		   &_work,
-		   (worker_t)&PX4FLOW::cycle_trampoline,
-		   this,
-		   USEC2TICK(PX4FLOW_CONVERSION_INTERVAL));
 }
 
 void
@@ -647,14 +662,41 @@ start()
 	}
 
 	/* create the driver */
-	g_dev = new PX4FLOW(PX4FLOW_BUS);
+	g_dev = new PX4FLOW(PX4_I2C_BUS_EXPANSION);
 
 	if (g_dev == nullptr) {
 		goto fail;
 	}
 
 	if (OK != g_dev->init()) {
-		goto fail;
+
+		#ifdef PX4_I2C_BUS_ESC
+		delete g_dev;
+		/* try 2nd bus */
+		g_dev = new PX4FLOW(PX4_I2C_BUS_ESC);
+
+		if (g_dev == nullptr) {
+			goto fail;
+		}
+
+		if (OK != g_dev->init()) {
+		#endif
+
+			delete g_dev;
+			/* try 3rd bus */
+			g_dev = new PX4FLOW(PX4_I2C_BUS_ONBOARD);
+
+			if (g_dev == nullptr) {
+				goto fail;
+			}
+
+			if (OK != g_dev->init()) {
+				goto fail;
+			}
+
+		#ifdef PX4_I2C_BUS_ESC
+		}
+		#endif
 	}
 
 	/* set the poll rate to default, starts automatic data collection */
@@ -683,7 +725,8 @@ fail:
 /**
  * Stop the driver
  */
-void stop()
+void
+stop()
 {
 	if (g_dev != nullptr) {
 		delete g_dev;
@@ -714,6 +757,7 @@ test()
 		err(1, "%s open failed (try 'px4flow start' if the driver is not running", PX4FLOW_DEVICE_PATH);
 	}
 
+
 	/* do a simple demand read */
 	sz = read(fd, &report, sizeof(report));
 
@@ -723,18 +767,18 @@ test()
 	}
 
 	warnx("single read");
-	warnx("flowx: %0.2f m/s", (double)report.flow_comp_x_m);
-	warnx("flowy: %0.2f m/s", (double)report.flow_comp_y_m);
-	warnx("time:        %lld", report.timestamp);
-
+	warnx("pixel_flow_x_integral: %i", f_integral.pixel_flow_x_integral);
+	warnx("pixel_flow_y_integral: %i", f_integral.pixel_flow_y_integral);
+	warnx("framecount_integral: %u",
+	      f_integral.frame_count_since_last_readout);
 
-	/* start the sensor polling at 2Hz */
-	if (OK != ioctl(fd, SENSORIOCSPOLLRATE, 2)) {
-		errx(1, "failed to set 2Hz poll rate");
+	/* start the sensor polling at 10Hz */
+	if (OK != ioctl(fd, SENSORIOCSPOLLRATE, 10)) {
+		errx(1, "failed to set 10Hz poll rate");
 	}
 
 	/* read the sensor 5x and report each value */
-	for (unsigned i = 0; i < 5; i++) {
+	for (unsigned i = 0; i < 10; i++) {
 		struct pollfd fds;
 
 		/* wait for data to be ready */
@@ -754,9 +798,22 @@ test()
 		}
 
 		warnx("periodic read %u", i);
-		warnx("flowx: %0.2f m/s", (double)report.flow_comp_x_m);
-		warnx("flowy: %0.2f m/s", (double)report.flow_comp_y_m);
-		warnx("time:        %lld", report.timestamp);
+
+		warnx("framecount_total: %u", f.frame_count);
+		warnx("framecount_integral: %u",
+		      f_integral.frame_count_since_last_readout);
+		warnx("pixel_flow_x_integral: %i", f_integral.pixel_flow_x_integral);
+		warnx("pixel_flow_y_integral: %i", f_integral.pixel_flow_y_integral);
+		warnx("gyro_x_rate_integral: %i", f_integral.gyro_x_rate_integral);
+		warnx("gyro_y_rate_integral: %i", f_integral.gyro_y_rate_integral);
+		warnx("gyro_z_rate_integral: %i", f_integral.gyro_z_rate_integral);
+		warnx("integration_timespan [us]: %u", f_integral.integration_timespan);
+		warnx("ground_distance: %0.2f m",
+		      (double) f_integral.ground_distance / 1000);
+		warnx("time since last sonar update [us]: %i",
+		      f_integral.time_since_last_sonar_update);
+		warnx("quality integration average : %i", f_integral.qual);
+		warnx("quality : %i", f.qual);
 
 
 	}
diff --git a/src/drivers/px4io/px4io.cpp b/src/drivers/px4io/px4io.cpp
index 6f02ba62c..58390ba4c 100644
--- a/src/drivers/px4io/px4io.cpp
+++ b/src/drivers/px4io/px4io.cpp
@@ -1160,52 +1160,54 @@ PX4IO::io_set_arming_state()
 	actuator_armed_s	armed;		///< system armed state
 	vehicle_control_mode_s	control_mode;	///< vehicle_control_mode
 
-	orb_copy(ORB_ID(actuator_armed), _t_actuator_armed, &armed);
-	orb_copy(ORB_ID(vehicle_control_mode), _t_vehicle_control_mode, &control_mode);
+	int have_armed = orb_copy(ORB_ID(actuator_armed), _t_actuator_armed, &armed);
+	int have_control_mode = orb_copy(ORB_ID(vehicle_control_mode), _t_vehicle_control_mode, &control_mode);
 
 	uint16_t set = 0;
 	uint16_t clear = 0;
 
-	if (armed.armed) {
-		set |= PX4IO_P_SETUP_ARMING_FMU_ARMED;
-
-	} else {
-		clear |= PX4IO_P_SETUP_ARMING_FMU_ARMED;
-	}
-
-	if (armed.lockdown && !_lockdown_override) {
-		set |= PX4IO_P_SETUP_ARMING_LOCKDOWN;
-	} else {
-		clear |= PX4IO_P_SETUP_ARMING_LOCKDOWN;
-	}
+        if (have_armed == OK) {
+		if (armed.armed) {
+			set |= PX4IO_P_SETUP_ARMING_FMU_ARMED;
+		} else {
+			clear |= PX4IO_P_SETUP_ARMING_FMU_ARMED;
+		}
 
-	/* Do not set failsafe if circuit breaker is enabled */
-	if (armed.force_failsafe && !_cb_flighttermination) {
-		set |= PX4IO_P_SETUP_ARMING_FORCE_FAILSAFE;
-	} else {
-		clear |= PX4IO_P_SETUP_ARMING_FORCE_FAILSAFE;
-	}
+		if (armed.lockdown && !_lockdown_override) {
+			set |= PX4IO_P_SETUP_ARMING_LOCKDOWN;
+		} else {
+			clear |= PX4IO_P_SETUP_ARMING_LOCKDOWN;
+		}
 
-	// XXX this is for future support in the commander
-	// but can be removed if unneeded
-	// if (armed.termination_failsafe) {
-	// 	set |= PX4IO_P_SETUP_ARMING_TERMINATION_FAILSAFE;
-	// } else {
-	// 	clear |= PX4IO_P_SETUP_ARMING_TERMINATION_FAILSAFE;
-	// }
+		/* Do not set failsafe if circuit breaker is enabled */
+		if (armed.force_failsafe && !_cb_flighttermination) {
+			set |= PX4IO_P_SETUP_ARMING_FORCE_FAILSAFE;
+		} else {
+			clear |= PX4IO_P_SETUP_ARMING_FORCE_FAILSAFE;
+		}
 
-	if (armed.ready_to_arm) {
-		set |= PX4IO_P_SETUP_ARMING_IO_ARM_OK;
+		// XXX this is for future support in the commander
+		// but can be removed if unneeded
+		// if (armed.termination_failsafe) {
+		// 	set |= PX4IO_P_SETUP_ARMING_TERMINATION_FAILSAFE;
+		// } else {
+		// 	clear |= PX4IO_P_SETUP_ARMING_TERMINATION_FAILSAFE;
+		// }
 
-	} else {
-		clear |= PX4IO_P_SETUP_ARMING_IO_ARM_OK;
+		if (armed.ready_to_arm) {
+			set |= PX4IO_P_SETUP_ARMING_IO_ARM_OK;
+			
+		} else {
+			clear |= PX4IO_P_SETUP_ARMING_IO_ARM_OK;
+		}
 	}
 
-	if (control_mode.flag_external_manual_override_ok) {
-		set |= PX4IO_P_SETUP_ARMING_MANUAL_OVERRIDE_OK;
-
-	} else {
-		clear |= PX4IO_P_SETUP_ARMING_MANUAL_OVERRIDE_OK;
+	if (have_control_mode == OK) {
+		if (control_mode.flag_external_manual_override_ok) {
+			set |= PX4IO_P_SETUP_ARMING_MANUAL_OVERRIDE_OK;
+		} else {
+			clear |= PX4IO_P_SETUP_ARMING_MANUAL_OVERRIDE_OK;
+		}
 	}
 
 	return io_reg_modify(PX4IO_PAGE_SETUP, PX4IO_P_SETUP_ARMING, clear, set);
@@ -2198,7 +2200,7 @@ PX4IO::ioctl(file * filep, int cmd, unsigned long arg)
 		struct pwm_output_values* pwm = (struct pwm_output_values*)arg;
 		if (pwm->channel_count > _max_actuators)
 			/* fail with error */
-			return E2BIG;
+			return -E2BIG;
 
 		/* copy values to registers in IO */
 		ret = io_reg_set(PX4IO_PAGE_FAILSAFE_PWM, 0, pwm->values, pwm->channel_count);
@@ -2217,7 +2219,7 @@ PX4IO::ioctl(file * filep, int cmd, unsigned long arg)
 		struct pwm_output_values* pwm = (struct pwm_output_values*)arg;
 		if (pwm->channel_count > _max_actuators)
 			/* fail with error */
-			return E2BIG;
+			return -E2BIG;
 
 		/* copy values to registers in IO */
 		ret = io_reg_set(PX4IO_PAGE_DISARMED_PWM, 0, pwm->values, pwm->channel_count);
@@ -2236,7 +2238,7 @@ PX4IO::ioctl(file * filep, int cmd, unsigned long arg)
 		struct pwm_output_values* pwm = (struct pwm_output_values*)arg;
 		if (pwm->channel_count > _max_actuators)
 			/* fail with error */
-			return E2BIG;
+			return -E2BIG;
 
 		/* copy values to registers in IO */
 		ret = io_reg_set(PX4IO_PAGE_CONTROL_MIN_PWM, 0, pwm->values, pwm->channel_count);
@@ -2255,7 +2257,7 @@ PX4IO::ioctl(file * filep, int cmd, unsigned long arg)
 		struct pwm_output_values* pwm = (struct pwm_output_values*)arg;
 		if (pwm->channel_count > _max_actuators)
 			/* fail with error */
-			return E2BIG;
+			return -E2BIG;
 
 		/* copy values to registers in IO */
 		ret = io_reg_set(PX4IO_PAGE_CONTROL_MAX_PWM, 0, pwm->values, pwm->channel_count);
@@ -2592,9 +2594,9 @@ PX4IO::ioctl(file * filep, int cmd, unsigned long arg)
 		   on param_get() 
 		*/
 		struct pwm_output_rc_config* config = (struct pwm_output_rc_config*)arg;
-		if (config->channel >= _max_actuators) {
+		if (config->channel >= RC_INPUT_MAX_CHANNELS) {
 			/* fail with error */
-			return E2BIG;
+			return -E2BIG;
 		}
 
 		/* copy values to registers in IO */
diff --git a/src/drivers/trone/module.mk b/src/drivers/trone/module.mk
new file mode 100644
index 000000000..38499c6c3
--- /dev/null
+++ b/src/drivers/trone/module.mk
@@ -0,0 +1,44 @@
+############################################################################
+#
+#   Copyright (c) 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.
+#
+############################################################################
+
+#
+# Makefile to build the TeraRanger One range finder driver
+#
+
+MODULE_COMMAND	= trone
+
+SRCS		= trone.cpp
+
+MODULE_STACKSIZE = 1200
+
+MAXOPTIMIZATION = -Os
diff --git a/src/drivers/trone/trone.cpp b/src/drivers/trone/trone.cpp
new file mode 100644
index 000000000..2f2f692a1
--- /dev/null
+++ b/src/drivers/trone/trone.cpp
@@ -0,0 +1,913 @@
+/****************************************************************************
+ *
+ *   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 trone.cpp
+ * @author Luis Rodrigues
+ *
+ * Driver for the TeraRanger One range finders connected via I2C.
+ */
+
+#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 <systemlib/perf_counter.h>
+#include <systemlib/err.h>
+
+#include <drivers/drv_hrt.h>
+#include <drivers/drv_range_finder.h>
+#include <drivers/device/ringbuffer.h>
+
+#include <uORB/uORB.h>
+#include <uORB/topics/subsystem_info.h>
+
+#include <board_config.h>
+
+/* Configuration Constants */
+#define TRONE_BUS 		PX4_I2C_BUS_EXPANSION
+#define TRONE_BASEADDR 		0x30 /* 7-bit address */
+#define TRONE_DEVICE_PATH 	"/dev/trone"
+
+/* TRONE Registers addresses */
+
+#define TRONE_MEASURE_REG	0x00		/* Measure range register */
+
+/* Device limits */
+#define TRONE_MIN_DISTANCE (0.20f)
+#define TRONE_MAX_DISTANCE (14.00f)
+
+#define TRONE_CONVERSION_INTERVAL 50000 /* 50ms */
+
+/* oddly, ERROR is not defined for c++ */
+#ifdef ERROR
+# undef ERROR
+#endif
+static const int ERROR = -1;
+
+#ifndef CONFIG_SCHED_WORKQUEUE
+# error This requires CONFIG_SCHED_WORKQUEUE.
+#endif
+
+class TRONE : public device::I2C
+{
+public:
+	TRONE(int bus = TRONE_BUS, int address = TRONE_BASEADDR);
+	virtual ~TRONE();
+
+	virtual int 		init();
+
+	virtual ssize_t		read(struct file *filp, char *buffer, size_t buflen);
+	virtual int			ioctl(struct file *filp, int cmd, unsigned long arg);
+
+	/**
+	* Diagnostics - print some basic information about the driver.
+	*/
+	void				print_info();
+
+protected:
+	virtual int			probe();
+
+private:
+	float				_min_distance;
+	float				_max_distance;
+	work_s				_work;
+	RingBuffer			*_reports;
+	bool				_sensor_ok;
+	int					_measure_ticks;
+	bool				_collect_phase;
+	int					_class_instance;
+
+	orb_advert_t		_range_finder_topic;
+
+	perf_counter_t		_sample_perf;
+	perf_counter_t		_comms_errors;
+	perf_counter_t		_buffer_overflows;
+
+	/**
+	* Test whether the device supported by the driver is present at a
+	* specific address.
+	*
+	* @param address	The I2C bus address to probe.
+	* @return		True if the device is present.
+	*/
+	int					probe_address(uint8_t address);
+
+	/**
+	* Initialise the automatic measurement state machine and start it.
+	*
+	* @note This function is called at open and error time.  It might make sense
+	*       to make it more aggressive about resetting the bus in case of errors.
+	*/
+	void				start();
+
+	/**
+	* Stop the automatic measurement state machine.
+	*/
+	void				stop();
+
+	/**
+	* Set the min and max distance thresholds if you want the end points of the sensors
+	* range to be brought in at all, otherwise it will use the defaults TRONE_MIN_DISTANCE
+	* and TRONE_MAX_DISTANCE
+	*/
+	void				set_minimum_distance(float min);
+	void				set_maximum_distance(float max);
+	float				get_minimum_distance();
+	float				get_maximum_distance();
+
+	/**
+	* Perform a poll cycle; collect from the previous measurement
+	* and start a new one.
+	*/
+	void				cycle();
+	int					measure();
+	int					collect();
+	/**
+	* Static trampoline from the workq context; because we don't have a
+	* generic workq wrapper yet.
+	*
+	* @param arg		Instance pointer for the driver that is polling.
+	*/
+	static void		cycle_trampoline(void *arg);
+
+
+};
+
+static const uint8_t crc_table[] = {
+    0x00, 0x07, 0x0e, 0x09, 0x1c, 0x1b, 0x12, 0x15, 0x38, 0x3f, 0x36, 0x31,
+    0x24, 0x23, 0x2a, 0x2d, 0x70, 0x77, 0x7e, 0x79, 0x6c, 0x6b, 0x62, 0x65,
+    0x48, 0x4f, 0x46, 0x41, 0x54, 0x53, 0x5a, 0x5d, 0xe0, 0xe7, 0xee, 0xe9,
+    0xfc, 0xfb, 0xf2, 0xf5, 0xd8, 0xdf, 0xd6, 0xd1, 0xc4, 0xc3, 0xca, 0xcd,
+    0x90, 0x97, 0x9e, 0x99, 0x8c, 0x8b, 0x82, 0x85, 0xa8, 0xaf, 0xa6, 0xa1,
+    0xb4, 0xb3, 0xba, 0xbd, 0xc7, 0xc0, 0xc9, 0xce, 0xdb, 0xdc, 0xd5, 0xd2,
+    0xff, 0xf8, 0xf1, 0xf6, 0xe3, 0xe4, 0xed, 0xea, 0xb7, 0xb0, 0xb9, 0xbe,
+    0xab, 0xac, 0xa5, 0xa2, 0x8f, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9d, 0x9a,
+    0x27, 0x20, 0x29, 0x2e, 0x3b, 0x3c, 0x35, 0x32, 0x1f, 0x18, 0x11, 0x16,
+    0x03, 0x04, 0x0d, 0x0a, 0x57, 0x50, 0x59, 0x5e, 0x4b, 0x4c, 0x45, 0x42,
+    0x6f, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7d, 0x7a, 0x89, 0x8e, 0x87, 0x80,
+    0x95, 0x92, 0x9b, 0x9c, 0xb1, 0xb6, 0xbf, 0xb8, 0xad, 0xaa, 0xa3, 0xa4,
+    0xf9, 0xfe, 0xf7, 0xf0, 0xe5, 0xe2, 0xeb, 0xec, 0xc1, 0xc6, 0xcf, 0xc8,
+    0xdd, 0xda, 0xd3, 0xd4, 0x69, 0x6e, 0x67, 0x60, 0x75, 0x72, 0x7b, 0x7c,
+    0x51, 0x56, 0x5f, 0x58, 0x4d, 0x4a, 0x43, 0x44, 0x19, 0x1e, 0x17, 0x10,
+    0x05, 0x02, 0x0b, 0x0c, 0x21, 0x26, 0x2f, 0x28, 0x3d, 0x3a, 0x33, 0x34,
+    0x4e, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5c, 0x5b, 0x76, 0x71, 0x78, 0x7f,
+    0x6a, 0x6d, 0x64, 0x63, 0x3e, 0x39, 0x30, 0x37, 0x22, 0x25, 0x2c, 0x2b,
+    0x06, 0x01, 0x08, 0x0f, 0x1a, 0x1d, 0x14, 0x13, 0xae, 0xa9, 0xa0, 0xa7,
+    0xb2, 0xb5, 0xbc, 0xbb, 0x96, 0x91, 0x98, 0x9f, 0x8a, 0x8d, 0x84, 0x83,
+    0xde, 0xd9, 0xd0, 0xd7, 0xc2, 0xc5, 0xcc, 0xcb, 0xe6, 0xe1, 0xe8, 0xef,
+    0xfa, 0xfd, 0xf4, 0xf3
+};
+
+uint8_t crc8(uint8_t *p, uint8_t len){
+        uint16_t i;
+        uint16_t crc = 0x0;
+
+        while (len--) {
+                i = (crc ^ *p++) & 0xFF;
+                crc = (crc_table[i] ^ (crc << 8)) & 0xFF;
+        }
+
+        return crc & 0xFF;
+}
+
+/*
+ * Driver 'main' command.
+ */
+extern "C" __EXPORT int trone_main(int argc, char *argv[]);
+
+TRONE::TRONE(int bus, int address) :
+	I2C("TRONE", TRONE_DEVICE_PATH, bus, address, 100000),
+	_min_distance(TRONE_MIN_DISTANCE),
+	_max_distance(TRONE_MAX_DISTANCE),
+	_reports(nullptr),
+	_sensor_ok(false),
+	_measure_ticks(0),
+	_collect_phase(false),
+	_class_instance(-1),
+	_range_finder_topic(-1),
+	_sample_perf(perf_alloc(PC_ELAPSED, "trone_read")),
+	_comms_errors(perf_alloc(PC_COUNT, "trone_comms_errors")),
+	_buffer_overflows(perf_alloc(PC_COUNT, "trone_buffer_overflows"))
+{
+	// up the retries since the device misses the first measure attempts
+	I2C::_retries = 3;
+
+	// enable debug() calls
+	_debug_enabled = false;
+
+	// work_cancel in the dtor will explode if we don't do this...
+	memset(&_work, 0, sizeof(_work));
+}
+
+TRONE::~TRONE()
+{
+	/* make sure we are truly inactive */
+	stop();
+
+	/* free any existing reports */
+	if (_reports != nullptr) {
+		delete _reports;
+	}
+	
+	if (_class_instance != -1) {
+		unregister_class_devname(RANGE_FINDER_DEVICE_PATH, _class_instance);
+	}
+	
+	// free perf counters
+	perf_free(_sample_perf);
+	perf_free(_comms_errors);
+	perf_free(_buffer_overflows);
+}
+
+int
+TRONE::init()
+{
+	int ret = ERROR;
+
+	/* do I2C init (and probe) first */
+	if (I2C::init() != OK) {
+		goto out;
+	}
+
+	/* allocate basic report buffers */
+	_reports = new RingBuffer(2, sizeof(range_finder_report));
+
+	if (_reports == nullptr) {
+		goto out;
+	}
+
+	_class_instance = register_class_devname(RANGE_FINDER_DEVICE_PATH);
+
+	if (_class_instance == CLASS_DEVICE_PRIMARY) {	
+		/* get a publish handle on the range finder topic */
+		struct range_finder_report rf_report;
+		measure();
+		_reports->get(&rf_report);
+		_range_finder_topic = orb_advertise(ORB_ID(sensor_range_finder), &rf_report);
+
+		if (_range_finder_topic < 0) {
+			debug("failed to create sensor_range_finder object. Did you start uOrb?");
+		}
+	}
+
+	ret = OK;
+	/* sensor is ok, but we don't really know if it is within range */
+	_sensor_ok = true;
+out:
+	return ret;
+}
+
+int
+TRONE::probe()
+{
+	return measure();
+}
+
+void
+TRONE::set_minimum_distance(float min)
+{
+	_min_distance = min;
+}
+
+void
+TRONE::set_maximum_distance(float max)
+{
+	_max_distance = max;
+}
+
+float
+TRONE::get_minimum_distance()
+{
+	return _min_distance;
+}
+
+float
+TRONE::get_maximum_distance()
+{
+	return _max_distance;
+}
+
+int
+TRONE::ioctl(struct file *filp, int cmd, unsigned long arg)
+{
+	switch (cmd) {
+
+	case SENSORIOCSPOLLRATE: {
+			switch (arg) {
+
+			/* switching to manual polling */
+			case SENSOR_POLLRATE_MANUAL:
+				stop();
+				_measure_ticks = 0;
+				return OK;
+
+			/* external signalling (DRDY) not supported */
+			case SENSOR_POLLRATE_EXTERNAL:
+
+			/* zero would be bad */
+			case 0:
+				return -EINVAL;
+
+			/* set default/max polling rate */
+			case SENSOR_POLLRATE_MAX:
+			case SENSOR_POLLRATE_DEFAULT: {
+					/* do we need to start internal polling? */
+					bool want_start = (_measure_ticks == 0);
+
+					/* set interval for next measurement to minimum legal value */
+					_measure_ticks = USEC2TICK(TRONE_CONVERSION_INTERVAL);
+
+					/* if we need to start the poll state machine, do it */
+					if (want_start) {
+						start();
+					}
+
+					return OK;
+				}
+
+			/* adjust to a legal polling interval in Hz */
+			default: {
+					/* do we need to start internal polling? */
+					bool want_start = (_measure_ticks == 0);
+
+					/* convert hz to tick interval via microseconds */
+					unsigned ticks = USEC2TICK(1000000 / arg);
+
+					/* check against maximum rate */
+					if (ticks < USEC2TICK(TRONE_CONVERSION_INTERVAL)) {
+						return -EINVAL;
+					}
+
+					/* update interval for next measurement */
+					_measure_ticks = ticks;
+
+					/* if we need to start the poll state machine, do it */
+					if (want_start) {
+						start();
+					}
+
+					return OK;
+				}
+			}
+		}
+
+	case SENSORIOCGPOLLRATE:
+		if (_measure_ticks == 0) {
+			return SENSOR_POLLRATE_MANUAL;
+		}
+
+		return (1000 / _measure_ticks);
+
+	case SENSORIOCSQUEUEDEPTH: {
+			/* lower bound is mandatory, upper bound is a sanity check */
+			if ((arg < 1) || (arg > 100)) {
+				return -EINVAL;
+			}
+
+			irqstate_t flags = irqsave();
+
+			if (!_reports->resize(arg)) {
+				irqrestore(flags);
+				return -ENOMEM;
+			}
+
+			irqrestore(flags);
+
+			return OK;
+		}
+
+	case SENSORIOCGQUEUEDEPTH:
+		return _reports->size();
+
+	case SENSORIOCRESET:
+		/* XXX implement this */
+		return -EINVAL;
+
+	case RANGEFINDERIOCSETMINIUMDISTANCE: {
+			set_minimum_distance(*(float *)arg);
+			return 0;
+		}
+		break;
+
+	case RANGEFINDERIOCSETMAXIUMDISTANCE: {
+			set_maximum_distance(*(float *)arg);
+			return 0;
+		}
+		break;
+
+	default:
+		/* give it to the superclass */
+		return I2C::ioctl(filp, cmd, arg);
+	}
+}
+
+ssize_t
+TRONE::read(struct file *filp, char *buffer, size_t buflen)
+{
+	unsigned count = buflen / sizeof(struct range_finder_report);
+	struct range_finder_report *rbuf = reinterpret_cast<struct range_finder_report *>(buffer);
+	int ret = 0;
+
+	/* buffer must be large enough */
+	if (count < 1) {
+		return -ENOSPC;
+	}
+
+	/* if automatic measurement is enabled */
+	if (_measure_ticks > 0) {
+
+		/*
+		 * While there is space in the caller's buffer, and reports, copy them.
+		 * Note that we may be pre-empted by the workq thread while we are doing this;
+		 * we are careful to avoid racing with them.
+		 */
+		while (count--) {
+			if (_reports->get(rbuf)) {
+				ret += sizeof(*rbuf);
+				rbuf++;
+			}
+		}
+
+		/* if there was no data, warn the caller */
+		return ret ? ret : -EAGAIN;
+	}
+
+	/* manual measurement - run one conversion */
+	do {
+		_reports->flush();
+
+		/* trigger a measurement */
+		if (OK != measure()) {
+			ret = -EIO;
+			break;
+		}
+
+		/* wait for it to complete */
+		usleep(TRONE_CONVERSION_INTERVAL);
+
+		/* run the collection phase */
+		if (OK != collect()) {
+			ret = -EIO;
+			break;
+		}
+
+		/* state machine will have generated a report, copy it out */
+		if (_reports->get(rbuf)) {
+			ret = sizeof(*rbuf);
+		}
+
+	} while (0);
+
+	return ret;
+}
+
+int
+TRONE::measure()
+{
+	int ret;
+
+	/*
+	 * Send the command to begin a measurement.
+	 */
+	const uint8_t cmd = TRONE_MEASURE_REG;
+	ret = transfer(&cmd, sizeof(cmd), nullptr, 0);
+
+	if (OK != ret) {
+		perf_count(_comms_errors);
+		log("i2c::transfer returned %d", ret);
+		return ret;
+	}
+
+	ret = OK;
+
+	return ret;
+}
+
+int
+TRONE::collect()
+{
+	int	ret = -EIO;
+
+        /* read from the sensor */
+	uint8_t val[3] = {0, 0, 0};
+
+	perf_begin(_sample_perf);
+
+	ret = transfer(nullptr, 0, &val[0], 3);
+
+	if (ret < 0) {
+		log("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 *  0.001f; /* mm 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);
+	report.distance = si_units;
+	report.valid = crc8(val, 2) == val[2] && 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;
+}
+
+void
+TRONE::start()
+{
+	/* reset the report ring and state machine */
+	_collect_phase = false;
+	_reports->flush();
+
+	/* schedule a cycle to start things */
+	work_queue(HPWORK, &_work, (worker_t)&TRONE::cycle_trampoline, this, 1);
+
+	/* notify about state change */
+	struct subsystem_info_s info = {
+		true,
+		true,
+		true,
+		SUBSYSTEM_TYPE_RANGEFINDER
+	};
+	static orb_advert_t pub = -1;
+
+	if (pub > 0) {
+		orb_publish(ORB_ID(subsystem_info), pub, &info);
+
+	} else {
+		pub = orb_advertise(ORB_ID(subsystem_info), &info);
+	}
+}
+
+void
+TRONE::stop()
+{
+	work_cancel(HPWORK, &_work);
+}
+
+void
+TRONE::cycle_trampoline(void *arg)
+{
+	TRONE *dev = (TRONE *)arg;
+
+	dev->cycle();
+}
+
+void
+TRONE::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(TRONE_CONVERSION_INTERVAL)) {
+
+			/* schedule a fresh cycle call when we are ready to measure again */
+			work_queue(HPWORK,
+				   &_work,
+				   (worker_t)&TRONE::cycle_trampoline,
+				   this,
+				   _measure_ticks - USEC2TICK(TRONE_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)&TRONE::cycle_trampoline,
+		   this,
+		   USEC2TICK(TRONE_CONVERSION_INTERVAL));
+}
+
+void
+TRONE::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);
+	_reports->print_info("report queue");
+}
+
+/**
+ * Local functions in support of the shell command.
+ */
+namespace trone
+{
+
+/* oddly, ERROR is not defined for c++ */
+#ifdef ERROR
+# undef ERROR
+#endif
+const int ERROR = -1;
+
+TRONE	*g_dev;
+
+void	start();
+void	stop();
+void	test();
+void	reset();
+void	info();
+
+/**
+ * Start the driver.
+ */
+void
+start()
+{
+	int fd;
+
+	if (g_dev != nullptr) {
+		errx(1, "already started");
+	}
+
+	/* create the driver */
+	g_dev = new TRONE(TRONE_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(TRONE_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 range_finder_report report;
+	ssize_t sz;
+	int ret;
+
+	int fd = open(TRONE_DEVICE_PATH, O_RDONLY);
+
+	if (fd < 0) {
+		err(1, "%s open failed (try 'trone start' if the driver is not running", TRONE_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("measurement: %0.2f m", (double)report.distance);
+	warnx("time:        %lld", report.timestamp);
+
+	/* start the sensor polling at 2Hz */
+	if (OK != ioctl(fd, SENSORIOCSPOLLRATE, 2)) {
+		errx(1, "failed to set 2Hz poll rate");
+	}
+
+	/* read the sensor 50x and report each value */
+	for (unsigned i = 0; i < 50; 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("valid %u", report.valid);
+		warnx("measurement: %0.3f", (double)report.distance);
+		warnx("time:        %lld", report.timestamp);
+	}
+
+	/* reset the sensor polling to default rate */
+	if (OK != ioctl(fd, SENSORIOCSPOLLRATE, SENSOR_POLLRATE_DEFAULT)) {
+		errx(1, "failed to set default poll rate");
+	}
+
+	errx(0, "PASS");
+}
+
+/**
+ * Reset the driver.
+ */
+void
+reset()
+{
+	int fd = open(TRONE_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
+
+int
+trone_main(int argc, char *argv[])
+{
+	/*
+	 * Start/load the driver.
+	 */
+	if (!strcmp(argv[1], "start")) {
+		trone::start();
+	}
+
+	/*
+	 * Stop the driver
+	 */
+	if (!strcmp(argv[1], "stop")) {
+		trone::stop();
+	}
+
+	/*
+	 * Test the driver/device.
+	 */
+	if (!strcmp(argv[1], "test")) {
+		trone::test();
+	}
+
+	/*
+	 * Reset the driver.
+	 */
+	if (!strcmp(argv[1], "reset")) {
+		trone::reset();
+	}
+
+	/*
+	 * Print driver information.
+	 */
+	if (!strcmp(argv[1], "info") || !strcmp(argv[1], "status")) {
+		trone::info();
+	}
+
+	errx(1, "unrecognized command, try 'start', 'test', 'reset' or 'info'");
+}
diff --git a/src/examples/flow_position_estimator/flow_position_estimator_main.c b/src/examples/flow_position_estimator/flow_position_estimator_main.c
index c775428ef..0b8c01f79 100644
--- a/src/examples/flow_position_estimator/flow_position_estimator_main.c
+++ b/src/examples/flow_position_estimator/flow_position_estimator_main.c
@@ -308,8 +308,8 @@ int flow_position_estimator_thread_main(int argc, char *argv[])
 					if (vehicle_liftoff || params.debug)
 					{
 						/* copy flow */
-						flow_speed[0] = flow.flow_comp_x_m;
-						flow_speed[1] = flow.flow_comp_y_m;
+						flow_speed[0] = flow.pixel_flow_x_integral / (flow.integration_timespan / 1e6f) * flow.ground_distance_m;
+						flow_speed[1] = flow.pixel_flow_y_integral / (flow.integration_timespan / 1e6f) * flow.ground_distance_m;
 						flow_speed[2] = 0.0f;
 
 						/* convert to bodyframe velocity */
diff --git a/src/modules/mavlink/mavlink_main.cpp b/src/modules/mavlink/mavlink_main.cpp
index fb9f65cf5..29b7ec7b7 100644
--- a/src/modules/mavlink/mavlink_main.cpp
+++ b/src/modules/mavlink/mavlink_main.cpp
@@ -1405,7 +1405,7 @@ Mavlink::task_main(int argc, char *argv[])
 		configure_stream("POSITION_TARGET_GLOBAL_INT", 3.0f);
 		configure_stream("ATTITUDE_TARGET", 3.0f);
 		configure_stream("DISTANCE_SENSOR", 0.5f);
-		configure_stream("OPTICAL_FLOW", 5.0f);
+		configure_stream("OPTICAL_FLOW_RAD", 5.0f);
 		break;
 
 	case MAVLINK_MODE_ONBOARD:
diff --git a/src/modules/mavlink/mavlink_messages.cpp b/src/modules/mavlink/mavlink_messages.cpp
index 978aee118..a8f956ad0 100644
--- a/src/modules/mavlink/mavlink_messages.cpp
+++ b/src/modules/mavlink/mavlink_messages.cpp
@@ -1834,33 +1834,32 @@ protected:
 	}
 };
 
-
-class MavlinkStreamOpticalFlow : public MavlinkStream
+class MavlinkStreamOpticalFlowRad : public MavlinkStream
 {
 public:
 	const char *get_name() const
 	{
-		return MavlinkStreamOpticalFlow::get_name_static();
+		return MavlinkStreamOpticalFlowRad::get_name_static();
 	}
 
 	static const char *get_name_static()
 	{
-		return "OPTICAL_FLOW";
+		return "OPTICAL_FLOW_RAD";
 	}
 
 	uint8_t get_id()
 	{
-		return MAVLINK_MSG_ID_OPTICAL_FLOW;
+		return MAVLINK_MSG_ID_OPTICAL_FLOW_RAD;
 	}
 
 	static MavlinkStream *new_instance(Mavlink *mavlink)
 	{
-		return new MavlinkStreamOpticalFlow(mavlink);
+		return new MavlinkStreamOpticalFlowRad(mavlink);
 	}
 
 	unsigned get_size()
 	{
-		return _flow_sub->is_published() ? (MAVLINK_MSG_ID_OPTICAL_FLOW_LEN + MAVLINK_NUM_NON_PAYLOAD_BYTES) : 0;
+		return _flow_sub->is_published() ? (MAVLINK_MSG_ID_OPTICAL_FLOW_RAD_LEN + MAVLINK_NUM_NON_PAYLOAD_BYTES) : 0;
 	}
 
 private:
@@ -1868,11 +1867,11 @@ private:
 	uint64_t _flow_time;
 
 	/* do not allow top copying this class */
-	MavlinkStreamOpticalFlow(MavlinkStreamOpticalFlow &);
-	MavlinkStreamOpticalFlow& operator = (const MavlinkStreamOpticalFlow &);
+	MavlinkStreamOpticalFlowRad(MavlinkStreamOpticalFlowRad &);
+	MavlinkStreamOpticalFlowRad& operator = (const MavlinkStreamOpticalFlowRad &);
 
 protected:
-	explicit MavlinkStreamOpticalFlow(Mavlink *mavlink) : MavlinkStream(mavlink),
+	explicit MavlinkStreamOpticalFlowRad(Mavlink *mavlink) : MavlinkStream(mavlink),
 		_flow_sub(_mavlink->add_orb_subscription(ORB_ID(optical_flow))),
 		_flow_time(0)
 	{}
@@ -1882,18 +1881,23 @@ protected:
 		struct optical_flow_s flow;
 
 		if (_flow_sub->update(&_flow_time, &flow)) {
-			mavlink_optical_flow_t msg;
+			mavlink_optical_flow_rad_t msg;
 
 			msg.time_usec = flow.timestamp;
 			msg.sensor_id = flow.sensor_id;
-			msg.flow_x = flow.flow_raw_x;
-			msg.flow_y = flow.flow_raw_y;
-			msg.flow_comp_m_x = flow.flow_comp_x_m;
-			msg.flow_comp_m_y = flow.flow_comp_y_m;
+			msg.integrated_x = flow.pixel_flow_x_integral;
+			msg.integrated_y = flow.pixel_flow_y_integral;
+			msg.integrated_xgyro = flow.gyro_x_rate_integral;
+			msg.integrated_ygyro = flow.gyro_y_rate_integral;
+			msg.integrated_zgyro = flow.gyro_z_rate_integral;
+			msg.distance = flow.ground_distance_m;
 			msg.quality = flow.quality;
-			msg.ground_distance = flow.ground_distance_m;
+			msg.integration_time_us = flow.integration_timespan;
+			msg.sensor_id = flow.sensor_id;
+			msg.time_delta_distance_us = flow.time_since_last_sonar_update;
+			msg.temperature = flow.gyro_temperature;
 
-			_mavlink->send_message(MAVLINK_MSG_ID_OPTICAL_FLOW, &msg);
+			_mavlink->send_message(MAVLINK_MSG_ID_OPTICAL_FLOW_RAD, &msg);
 		}
 	}
 };
@@ -2199,7 +2203,7 @@ StreamListItem *streams_list[] = {
 	new StreamListItem(&MavlinkStreamAttitudeTarget::new_instance, &MavlinkStreamAttitudeTarget::get_name_static),
 	new StreamListItem(&MavlinkStreamRCChannelsRaw::new_instance, &MavlinkStreamRCChannelsRaw::get_name_static),
 	new StreamListItem(&MavlinkStreamManualControl::new_instance, &MavlinkStreamManualControl::get_name_static),
-	new StreamListItem(&MavlinkStreamOpticalFlow::new_instance, &MavlinkStreamOpticalFlow::get_name_static),
+	new StreamListItem(&MavlinkStreamOpticalFlowRad::new_instance, &MavlinkStreamOpticalFlowRad::get_name_static),
 	new StreamListItem(&MavlinkStreamAttitudeControls::new_instance, &MavlinkStreamAttitudeControls::get_name_static),
 	new StreamListItem(&MavlinkStreamNamedValueFloat::new_instance, &MavlinkStreamNamedValueFloat::get_name_static),
 	new StreamListItem(&MavlinkStreamCameraCapture::new_instance, &MavlinkStreamCameraCapture::get_name_static),
diff --git a/src/modules/mavlink/mavlink_receiver.cpp b/src/modules/mavlink/mavlink_receiver.cpp
index ca00d1a67..e98d72afe 100644
--- a/src/modules/mavlink/mavlink_receiver.cpp
+++ b/src/modules/mavlink/mavlink_receiver.cpp
@@ -144,8 +144,8 @@ MavlinkReceiver::handle_message(mavlink_message_t *msg)
 		handle_message_command_int(msg);
 		break;
 
-	case MAVLINK_MSG_ID_OPTICAL_FLOW:
-		handle_message_optical_flow(msg);
+	case MAVLINK_MSG_ID_OPTICAL_FLOW_RAD:
+		handle_message_optical_flow_rad(msg);
 		break;
 
 	case MAVLINK_MSG_ID_SET_MODE:
@@ -352,24 +352,27 @@ MavlinkReceiver::handle_message_command_int(mavlink_message_t *msg)
 }
 
 void
-MavlinkReceiver::handle_message_optical_flow(mavlink_message_t *msg)
+MavlinkReceiver::handle_message_optical_flow_rad(mavlink_message_t *msg)
 {
 	/* optical flow */
-	mavlink_optical_flow_t flow;
-	mavlink_msg_optical_flow_decode(msg, &flow);
+	mavlink_optical_flow_rad_t flow;
+	mavlink_msg_optical_flow_rad_decode(msg, &flow);
 
 	struct optical_flow_s f;
 	memset(&f, 0, sizeof(f));
 
-	f.timestamp = hrt_absolute_time();
-	f.flow_timestamp = flow.time_usec;
-	f.flow_raw_x = flow.flow_x;
-	f.flow_raw_y = flow.flow_y;
-	f.flow_comp_x_m = flow.flow_comp_m_x;
-	f.flow_comp_y_m = flow.flow_comp_m_y;
-	f.ground_distance_m = flow.ground_distance;
+	f.timestamp = flow.time_usec;
+	f.integration_timespan = flow.integration_time_us;
+	f.pixel_flow_x_integral = flow.integrated_x;
+	f.pixel_flow_y_integral = flow.integrated_y;
+	f.gyro_x_rate_integral = flow.integrated_xgyro;
+	f.gyro_y_rate_integral = flow.integrated_ygyro;
+	f.gyro_z_rate_integral = flow.integrated_zgyro;
+	f.time_since_last_sonar_update = flow.time_delta_distance_us;
+	f.ground_distance_m = flow.distance;
 	f.quality = flow.quality;
 	f.sensor_id = flow.sensor_id;
+	f.gyro_temperature = flow.temperature;
 
 	if (_flow_pub < 0) {
 		_flow_pub = orb_advertise(ORB_ID(optical_flow), &f);
@@ -389,13 +392,18 @@ MavlinkReceiver::handle_message_hil_optical_flow(mavlink_message_t *msg)
 	struct optical_flow_s f;
 	memset(&f, 0, sizeof(f));
 
-	f.timestamp = hrt_absolute_time();
-	f.flow_timestamp = flow.time_usec;
-	f.flow_raw_x = flow.integrated_x;
-	f.flow_raw_y = flow.integrated_y;
+	f.timestamp = hrt_absolute_time(); // XXX we rely on the system time for now and not flow.time_usec;
+	f.integration_timespan = flow.integration_time_us;
+	f.pixel_flow_x_integral = flow.integrated_x;
+	f.pixel_flow_y_integral = flow.integrated_y;
+	f.gyro_x_rate_integral = flow.integrated_xgyro;
+	f.gyro_y_rate_integral = flow.integrated_ygyro;
+	f.gyro_z_rate_integral = flow.integrated_zgyro;
+	f.time_since_last_sonar_update = flow.time_delta_distance_us;
 	f.ground_distance_m = flow.distance;
 	f.quality = flow.quality;
 	f.sensor_id = flow.sensor_id;
+	f.gyro_temperature = flow.temperature;
 
 	if (_flow_pub < 0) {
 		_flow_pub = orb_advertise(ORB_ID(optical_flow), &f);
diff --git a/src/modules/mavlink/mavlink_receiver.h b/src/modules/mavlink/mavlink_receiver.h
index e5f2c6a73..a057074a7 100644
--- a/src/modules/mavlink/mavlink_receiver.h
+++ b/src/modules/mavlink/mavlink_receiver.h
@@ -112,7 +112,7 @@ private:
 	void handle_message(mavlink_message_t *msg);
 	void handle_message_command_long(mavlink_message_t *msg);
 	void handle_message_command_int(mavlink_message_t *msg);
-	void handle_message_optical_flow(mavlink_message_t *msg);
+	void handle_message_optical_flow_rad(mavlink_message_t *msg);
 	void handle_message_hil_optical_flow(mavlink_message_t *msg);
 	void handle_message_set_mode(mavlink_message_t *msg);
 	void handle_message_vicon_position_estimate(mavlink_message_t *msg);
diff --git a/src/modules/position_estimator_inav/position_estimator_inav_main.c b/src/modules/position_estimator_inav/position_estimator_inav_main.c
index e736a86d7..296919c04 100644
--- a/src/modules/position_estimator_inav/position_estimator_inav_main.c
+++ b/src/modules/position_estimator_inav/position_estimator_inav_main.c
@@ -296,7 +296,7 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 	float w_flow = 0.0f;
 
 	float sonar_prev = 0.0f;
-	hrt_abstime flow_prev = 0;			// time of last flow measurement
+	//hrt_abstime flow_prev = 0;			// time of last flow measurement
 	hrt_abstime sonar_time = 0;			// time of last sonar measurement (not filtered)
 	hrt_abstime sonar_valid_time = 0;	// time of last sonar measurement used for correction (filtered)
 
@@ -489,8 +489,8 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 				orb_copy(ORB_ID(optical_flow), optical_flow_sub, &flow);
 
 				/* calculate time from previous update */
-				float flow_dt = flow_prev > 0 ? (flow.flow_timestamp - flow_prev) * 1e-6f : 0.1f;
-				flow_prev = flow.flow_timestamp;
+//				float flow_dt = flow_prev > 0 ? (flow.flow_timestamp - flow_prev) * 1e-6f : 0.1f;
+//				flow_prev = flow.flow_timestamp;
 
 				if ((flow.ground_distance_m > 0.31f) &&
 					(flow.ground_distance_m < 4.0f) &&
@@ -548,8 +548,9 @@ int position_estimator_inav_thread_main(int argc, char *argv[])
 
 					/* convert raw flow to angular flow (rad/s) */
 					float flow_ang[2];
-					flow_ang[0] = flow.flow_raw_x * params.flow_k / 1000.0f / flow_dt;
-					flow_ang[1] = flow.flow_raw_y * params.flow_k / 1000.0f / flow_dt;
+					//todo check direction of x und y axis
+					flow_ang[0] = flow.pixel_flow_x_integral/(float)flow.integration_timespan*1000000.0f;//flow.flow_raw_x * params.flow_k / 1000.0f / flow_dt;
+					flow_ang[1] = flow.pixel_flow_y_integral/(float)flow.integration_timespan*1000000.0f;//flow.flow_raw_y * params.flow_k / 1000.0f / flow_dt;
 					/* flow measurements vector */
 					float flow_m[3];
 					flow_m[0] = -flow_ang[0] * flow_dist;
diff --git a/src/modules/px4iofirmware/registers.c b/src/modules/px4iofirmware/registers.c
index a1a02965f..f0c2cfd26 100644
--- a/src/modules/px4iofirmware/registers.c
+++ b/src/modules/px4iofirmware/registers.c
@@ -412,7 +412,6 @@ registers_set(uint8_t page, uint8_t offset, const uint16_t *values, unsigned num
 		 * text handling function.
 		 */
 		return mixer_handle_text(values, num_values * sizeof(*values));
-		break;
 
 	default:
 		/* avoid offset wrap */
@@ -584,10 +583,7 @@ registers_set_one(uint8_t page, uint8_t offset, uint16_t value)
 			break;
 
 		case PX4IO_P_SETUP_REBOOT_BL:
-			// do not reboot if FMU is armed and IO's safety is off
-			// this state defines an active system.
-			if ((r_status_flags & PX4IO_P_STATUS_FLAGS_SAFETY_OFF) &&
-			    (r_status_flags & PX4IO_P_SETUP_ARMING_FMU_ARMED)) {
+			if (r_status_flags & PX4IO_P_STATUS_FLAGS_SAFETY_OFF) {
 				// don't allow reboot while armed
 				break;
 			}
@@ -633,12 +629,9 @@ registers_set_one(uint8_t page, uint8_t offset, uint16_t value)
 	case PX4IO_PAGE_RC_CONFIG: {
 
 		/**
-		 * do not allow a RC config change while outputs armed
-		 * = FMU is armed and IO's safety is off
-		 * this state defines an active system.
+		 * do not allow a RC config change while safety is off
 		 */
-		if ((r_status_flags & PX4IO_P_STATUS_FLAGS_SAFETY_OFF) &&
-			    (r_status_flags & PX4IO_P_SETUP_ARMING_FMU_ARMED)) {
+		if (r_status_flags & PX4IO_P_STATUS_FLAGS_SAFETY_OFF) {
 			break;
 		}
 
diff --git a/src/modules/sdlog2/sdlog2.c b/src/modules/sdlog2/sdlog2.c
index 8638a4904..0b6861d2a 100644
--- a/src/modules/sdlog2/sdlog2.c
+++ b/src/modules/sdlog2/sdlog2.c
@@ -1518,11 +1518,14 @@ int sdlog2_thread_main(int argc, char *argv[])
 		/* --- FLOW --- */
 		if (copy_if_updated(ORB_ID(optical_flow), subs.flow_sub, &buf.flow)) {
 			log_msg.msg_type = LOG_FLOW_MSG;
-			log_msg.body.log_FLOW.flow_raw_x = buf.flow.flow_raw_x;
-			log_msg.body.log_FLOW.flow_raw_y = buf.flow.flow_raw_y;
-			log_msg.body.log_FLOW.flow_comp_x = buf.flow.flow_comp_x_m;
-			log_msg.body.log_FLOW.flow_comp_y = buf.flow.flow_comp_y_m;
-			log_msg.body.log_FLOW.distance = buf.flow.ground_distance_m;
+			log_msg.body.log_FLOW.ground_distance_m = buf.flow.ground_distance_m;
+			log_msg.body.log_FLOW.gyro_temperature = buf.flow.gyro_temperature;
+			log_msg.body.log_FLOW.gyro_x_rate_integral = buf.flow.gyro_x_rate_integral;
+			log_msg.body.log_FLOW.gyro_y_rate_integral = buf.flow.gyro_y_rate_integral;
+			log_msg.body.log_FLOW.gyro_z_rate_integral = buf.flow.gyro_z_rate_integral;
+			log_msg.body.log_FLOW.integration_timespan = buf.flow.integration_timespan;
+			log_msg.body.log_FLOW.pixel_flow_x_integral = buf.flow.pixel_flow_x_integral;
+			log_msg.body.log_FLOW.pixel_flow_y_integral = buf.flow.pixel_flow_y_integral;
 			log_msg.body.log_FLOW.quality = buf.flow.quality;
 			log_msg.body.log_FLOW.sensor_id = buf.flow.sensor_id;
 			LOGBUFFER_WRITE_AND_COUNT(FLOW);
diff --git a/src/modules/sdlog2/sdlog2_messages.h b/src/modules/sdlog2/sdlog2_messages.h
index fa9bdacb8..30491036a 100644
--- a/src/modules/sdlog2/sdlog2_messages.h
+++ b/src/modules/sdlog2/sdlog2_messages.h
@@ -200,13 +200,19 @@ struct log_ARSP_s {
 /* --- FLOW - OPTICAL FLOW --- */
 #define LOG_FLOW_MSG 15
 struct log_FLOW_s {
-	int16_t flow_raw_x;
-	int16_t flow_raw_y;
-	float flow_comp_x;
-	float flow_comp_y;
-	float distance;
-	uint8_t	quality;
+	uint64_t timestamp;
 	uint8_t sensor_id;
+	float pixel_flow_x_integral;
+	float pixel_flow_y_integral;
+	float gyro_x_rate_integral;
+	float gyro_y_rate_integral;
+	float gyro_z_rate_integral;
+	float ground_distance_m;
+	uint32_t integration_timespan;
+	uint32_t time_since_last_sonar_update;
+	uint16_t frame_count_since_last_readout;
+	int16_t gyro_temperature;
+	uint8_t	quality;
 };
 
 /* --- GPOS - GLOBAL POSITION ESTIMATE --- */
diff --git a/src/modules/uORB/Publication.cpp b/src/modules/uORB/Publication.cpp
index 05605417d..41a866968 100644
--- a/src/modules/uORB/Publication.cpp
+++ b/src/modules/uORB/Publication.cpp
@@ -46,6 +46,7 @@
 #include "topics/vehicle_attitude_setpoint.h"
 #include "topics/vehicle_rates_setpoint.h"
 #include "topics/actuator_outputs.h"
+#include "topics/actuator_direct.h"
 #include "topics/encoders.h"
 #include "topics/tecs_status.h"
 #include "topics/rc_channels.h"
@@ -77,6 +78,7 @@ template class __EXPORT Publication<vehicle_global_velocity_setpoint_s>;
 template class __EXPORT Publication<vehicle_attitude_setpoint_s>;
 template class __EXPORT Publication<vehicle_rates_setpoint_s>;
 template class __EXPORT Publication<actuator_outputs_s>;
+template class __EXPORT Publication<actuator_direct_s>;
 template class __EXPORT Publication<encoders_s>;
 template class __EXPORT Publication<tecs_status_s>;
 template class __EXPORT Publication<rc_channels_s>;
diff --git a/src/modules/uORB/objects_common.cpp b/src/modules/uORB/objects_common.cpp
index b91a00c1e..49dfc7834 100644
--- a/src/modules/uORB/objects_common.cpp
+++ b/src/modules/uORB/objects_common.cpp
@@ -192,6 +192,9 @@ ORB_DEFINE(actuator_outputs_1, struct actuator_outputs_s);
 ORB_DEFINE(actuator_outputs_2, struct actuator_outputs_s);
 ORB_DEFINE(actuator_outputs_3, struct actuator_outputs_s);
 
+#include "topics/actuator_direct.h"
+ORB_DEFINE(actuator_direct, struct actuator_direct_s);
+
 #include "topics/multirotor_motor_limits.h"
 ORB_DEFINE(multirotor_motor_limits, struct multirotor_motor_limits_s);
 
diff --git a/src/modules/uORB/topics/actuator_direct.h b/src/modules/uORB/topics/actuator_direct.h
new file mode 100644
index 000000000..5f9d0f56d
--- /dev/null
+++ b/src/modules/uORB/topics/actuator_direct.h
@@ -0,0 +1,69 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 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 actuator_direct.h
+ *
+ * Actuator direct values.
+ *
+ * Values published to this topic are the direct actuator values which
+ * should be passed to actuators, bypassing mixing
+ */
+
+#ifndef TOPIC_ACTUATOR_DIRECT_H
+#define TOPIC_ACTUATOR_DIRECT_H
+
+#include <stdint.h>
+#include "../uORB.h"
+
+#define NUM_ACTUATORS_DIRECT		16
+
+/**
+ * @addtogroup topics
+ * @{
+ */
+
+struct actuator_direct_s {
+	uint64_t timestamp;				/**< timestamp in us since system boot */
+	float values[NUM_ACTUATORS_DIRECT];		/**< actuator values, from -1 to 1 */
+	unsigned nvalues;				/**< number of valid values */
+};
+
+/**
+ * @}
+ */
+
+/* actuator direct ORB */
+ORB_DECLARE(actuator_direct);
+
+#endif // TOPIC_ACTUATOR_DIRECT_H
diff --git a/src/modules/uORB/topics/optical_flow.h b/src/modules/uORB/topics/optical_flow.h
index 0196ae86b..d3dc46ee0 100644
--- a/src/modules/uORB/topics/optical_flow.h
+++ b/src/modules/uORB/topics/optical_flow.h
@@ -55,16 +55,22 @@
  */
 struct optical_flow_s {
 
-	uint64_t timestamp;		/**< in microseconds since system start          */
-
-	uint64_t flow_timestamp;		/**< timestamp from flow sensor */
-	int16_t flow_raw_x;		/**< flow in pixels in X direction, not rotation-compensated */
-	int16_t flow_raw_y;		/**< flow in pixels in Y direction, not rotation-compensated */
-	float flow_comp_x_m;		/**< speed over ground in meters, rotation-compensated */
-	float flow_comp_y_m;		/**< speed over ground in meters, rotation-compensated */
-	float ground_distance_m;	/**< Altitude / distance to ground in meters */
-	uint8_t	quality;		/**< Quality of the measurement, 0: bad quality, 255: maximum quality */
+	uint64_t timestamp;		/**< in microseconds since system start  */
 	uint8_t sensor_id;		/**< id of the sensor emitting the flow value */
+	float pixel_flow_x_integral; /**< accumulated optical flow in radians around x axis */
+	float pixel_flow_y_integral; /**< accumulated optical flow in radians around y axis */
+	float gyro_x_rate_integral;	 /**< accumulated gyro value in radians around x axis */
+	float gyro_y_rate_integral;  /**< accumulated gyro value in radians around y axis */
+	float gyro_z_rate_integral;   /**< accumulated gyro value in radians around z axis */
+	float ground_distance_m;	 /**< Altitude / distance to ground in meters */
+	uint32_t integration_timespan; /**<accumulation timespan in microseconds     */
+	uint32_t time_since_last_sonar_update;/**< time since last sonar update in microseconds */
+	uint16_t frame_count_since_last_readout;/**< number of accumulated frames in timespan */
+	int16_t gyro_temperature;/**< 	Temperature * 100 in centi-degrees Celsius */
+	uint8_t	quality;		/**< Average of quality of accumulated frames, 0: bad quality, 255: maximum quality */
+
+
+
 
 };
 
diff --git a/src/modules/uavcan/actuators/esc.cpp b/src/modules/uavcan/actuators/esc.cpp
index 1d23099f3..9f682c7e1 100644
--- a/src/modules/uavcan/actuators/esc.cpp
+++ b/src/modules/uavcan/actuators/esc.cpp
@@ -76,7 +76,9 @@ int UavcanEscController::init()
 
 void UavcanEscController::update_outputs(float *outputs, unsigned num_outputs)
 {
-	if ((outputs == nullptr) || (num_outputs > uavcan::equipment::esc::RawCommand::FieldTypes::cmd::MaxSize)) {
+	if ((outputs == nullptr) || 
+            (num_outputs > uavcan::equipment::esc::RawCommand::FieldTypes::cmd::MaxSize) ||
+            (num_outputs > CONNECTED_ESC_MAX)) {
 		perf_count(_perfcnt_invalid_input);
 		return;
 	}
@@ -101,10 +103,15 @@ void UavcanEscController::update_outputs(float *outputs, unsigned num_outputs)
 	for (unsigned i = 0; i < num_outputs; i++) {
 		if (_armed_mask & MOTOR_BIT(i)) {
 			float scaled = (outputs[i] + 1.0F) * 0.5F * cmd_max;
-			if (scaled < 1.0F) {
-				scaled = 1.0F;  // Since we're armed, we don't want to stop it completely
-			}
-
+                        // trim negative values back to 0. Previously
+                        // we set this to 0.1, which meant motors kept
+                        // spinning when armed, but that should be a
+                        // policy decision for a specific vehicle
+                        // type, as it is not appropriate for all
+                        // types of vehicles (eg. fixed wing).
+			if (scaled < 0.0F) {
+				scaled = 0.0F;
+                        }
 			if (scaled > cmd_max) {
 				scaled = cmd_max;
 				perf_count(_perfcnt_scaling_error);
diff --git a/src/modules/uavcan/uavcan_main.cpp b/src/modules/uavcan/uavcan_main.cpp
index 2c543462e..8147a8b89 100644
--- a/src/modules/uavcan/uavcan_main.cpp
+++ b/src/modules/uavcan/uavcan_main.cpp
@@ -269,6 +269,24 @@ void UavcanNode::node_spin_once()
 	}
 }
 
+/*
+  add a fd to the list of polled events. This assumes you want
+  POLLIN for now.
+ */
+int UavcanNode::add_poll_fd(int fd)
+{
+	int ret = _poll_fds_num;
+	if (_poll_fds_num >= UAVCAN_NUM_POLL_FDS) {
+		errx(1, "uavcan: too many poll fds, exiting");
+	}
+	_poll_fds[_poll_fds_num] = ::pollfd();
+	_poll_fds[_poll_fds_num].fd = fd;
+	_poll_fds[_poll_fds_num].events = POLLIN;
+	_poll_fds_num += 1;
+	return ret;
+}
+
+
 int UavcanNode::run()
 {
 	(void)pthread_mutex_lock(&_node_mutex);
@@ -280,9 +298,9 @@ int UavcanNode::run()
 
 	_armed_sub = orb_subscribe(ORB_ID(actuator_armed));
 	_test_motor_sub = orb_subscribe(ORB_ID(test_motor));
+	_actuator_direct_sub = orb_subscribe(ORB_ID(actuator_direct));
 
-	actuator_outputs_s outputs;
-	memset(&outputs, 0, sizeof(outputs));
+	memset(&_outputs, 0, sizeof(_outputs));
 
 	const int busevent_fd = ::open(uavcan_stm32::BusEvent::DevName, 0);
 	if (busevent_fd < 0)
@@ -304,11 +322,15 @@ int UavcanNode::run()
 	 * the value returned from poll() to detect whether actuator control has timed out or not.
 	 * Instead, all ORB events need to be checked individually (see below).
 	 */
-	_poll_fds_num = 0;
-	_poll_fds[_poll_fds_num] = ::pollfd();
-	_poll_fds[_poll_fds_num].fd = busevent_fd;
-	_poll_fds[_poll_fds_num].events = POLLIN;
-	_poll_fds_num += 1;
+	add_poll_fd(busevent_fd);
+
+	/*
+	 * setup poll to look for actuator direct input if we are
+	 * subscribed to the topic
+	 */
+	if (_actuator_direct_sub != -1) {
+		_actuator_direct_poll_fd_num = add_poll_fd(_actuator_direct_sub);
+	}
 
 	while (!_task_should_exit) {
 		// update actuator controls subscriptions if needed
@@ -326,6 +348,8 @@ int UavcanNode::run()
 
 		node_spin_once();  // Non-blocking
 
+		bool new_output = false;
+
 		// this would be bad...
 		if (poll_ret < 0) {
 			log("poll error %d", errno);
@@ -333,24 +357,39 @@ int UavcanNode::run()
 		} else {
 			// get controls for required topics
 			bool controls_updated = false;
-			unsigned poll_id = 1;
 			for (unsigned i = 0; i < NUM_ACTUATOR_CONTROL_GROUPS; i++) {
 				if (_control_subs[i] > 0) {
-					if (_poll_fds[poll_id].revents & POLLIN) {
+					if (_poll_fds[_poll_ids[i]].revents & POLLIN) {
 						controls_updated = true;
 						orb_copy(_control_topics[i], _control_subs[i], &_controls[i]);
 					}
-					poll_id++;
 				}
 			}
 
+			/*
+			  see if we have any direct actuator updates
+			 */
+			if (_actuator_direct_sub != -1 && 
+			    (_poll_fds[_actuator_direct_poll_fd_num].revents & POLLIN) &&
+			    orb_copy(ORB_ID(actuator_direct), _actuator_direct_sub, &_actuator_direct) == OK &&
+			    !_test_in_progress) {
+				if (_actuator_direct.nvalues > NUM_ACTUATOR_OUTPUTS) {
+					_actuator_direct.nvalues = NUM_ACTUATOR_OUTPUTS;
+				}
+				memcpy(&_outputs.output[0], &_actuator_direct.values[0], 
+				       _actuator_direct.nvalues*sizeof(float));
+				_outputs.noutputs = _actuator_direct.nvalues;
+				new_output = true;
+			}
+
 			// can we mix?
 			if (_test_in_progress) {
-				float test_outputs[NUM_ACTUATOR_OUTPUTS] = {};
-				test_outputs[_test_motor.motor_number] = _test_motor.value*2.0f-1.0f;
-
-				// Output to the bus
-				_esc_controller.update_outputs(test_outputs, NUM_ACTUATOR_OUTPUTS);
+				memset(&_outputs, 0, sizeof(_outputs));
+				if (_test_motor.motor_number < NUM_ACTUATOR_OUTPUTS) {
+					_outputs.output[_test_motor.motor_number] = _test_motor.value*2.0f-1.0f;
+					_outputs.noutputs = _test_motor.motor_number+1;
+				}
+				new_output = true;
 			} else if (controls_updated && (_mixers != nullptr)) {
 
 				// XXX one output group has 8 outputs max,
@@ -358,39 +397,41 @@ int UavcanNode::run()
 				unsigned num_outputs_max = 8;
 
 				// Do mixing
-				outputs.noutputs = _mixers->mix(&outputs.output[0], num_outputs_max);
-				outputs.timestamp = hrt_absolute_time();
-
-				// iterate actuators
-				for (unsigned i = 0; i < outputs.noutputs; i++) {
-					// last resort: catch NaN, INF and out-of-band errors
-					if (!isfinite(outputs.output[i])) {
-						/*
-						 * Value is NaN, INF or out of band - set to the minimum value.
-						 * This will be clearly visible on the servo status and will limit the risk of accidentally
-						 * spinning motors. It would be deadly in flight.
-						 */
-						outputs.output[i] = -1.0f;
-					}
+				_outputs.noutputs = _mixers->mix(&_outputs.output[0], num_outputs_max);
 
-					// limit outputs to valid range
+				new_output = true;
+			}
+		}
 
-					// never go below min
-					if (outputs.output[i] < -1.0f) {
-						outputs.output[i] = -1.0f;
-					}
+		if (new_output) {
+			// iterate actuators, checking for valid values
+			for (uint8_t i = 0; i < _outputs.noutputs; i++) {
+				// last resort: catch NaN, INF and out-of-band errors
+				if (!isfinite(_outputs.output[i])) {
+					/*
+					 * Value is NaN, INF or out of band - set to the minimum value.
+					 * This will be clearly visible on the servo status and will limit the risk of accidentally
+					 * spinning motors. It would be deadly in flight.
+					 */
+					_outputs.output[i] = -1.0f;
+				}
 
-					// never go below max
-					if (outputs.output[i] > 1.0f) {
-						outputs.output[i] = 1.0f;
-					}
+				// never go below min
+				if (_outputs.output[i] < -1.0f) {
+					_outputs.output[i] = -1.0f;
 				}
 
-				// Output to the bus
-				_esc_controller.update_outputs(outputs.output, outputs.noutputs);
+				// never go above max
+				if (_outputs.output[i] > 1.0f) {
+					_outputs.output[i] = 1.0f;
+				}
 			}
+			// Output to the bus
+			_outputs.timestamp = hrt_absolute_time();
+			_esc_controller.update_outputs(_outputs.output, _outputs.noutputs);
 		}
 
+
 		// Check motor test state
 		bool updated = false;
 		orb_check(_test_motor_sub, &updated);
@@ -459,7 +500,6 @@ UavcanNode::subscribe()
 	uint32_t sub_groups = _groups_required & ~_groups_subscribed;
 	uint32_t unsub_groups = _groups_subscribed & ~_groups_required;
 	// the first fd used by CAN
-	_poll_fds_num = 1;
 	for (unsigned i = 0; i < NUM_ACTUATOR_CONTROL_GROUPS; i++) {
 		if (sub_groups & (1 << i)) {
 			warnx("subscribe to actuator_controls_%d", i);
@@ -472,9 +512,7 @@ UavcanNode::subscribe()
 		}
 
 		if (_control_subs[i] > 0) {
-			_poll_fds[_poll_fds_num].fd = _control_subs[i];
-			_poll_fds[_poll_fds_num].events = POLLIN;
-			_poll_fds_num++;
+			_poll_ids[i] = add_poll_fd(_control_subs[i]);
 		}
 	}
 }
@@ -572,6 +610,14 @@ UavcanNode::print_info()
 	       (unsigned)_groups_subscribed, (unsigned)_groups_required, _poll_fds_num);
 	printf("ESC mixer: %s\n", (_mixers == nullptr) ? "NONE" : "OK");
 
+	if (_outputs.noutputs != 0) {
+		printf("ESC output: ");
+		for (uint8_t i=0; i<_outputs.noutputs; i++) {
+			printf("%d ", (int)(_outputs.output[i]*1000));
+		}
+		printf("\n");
+	}
+
 	// Sensor bridges
 	auto br = _sensor_bridges.getHead();
 	while (br != nullptr) {
@@ -590,7 +636,7 @@ UavcanNode::print_info()
 static void print_usage()
 {
 	warnx("usage: \n"
-	      "\tuavcan {start|status|stop}");
+	      "\tuavcan {start|status|stop|arm|disarm}");
 }
 
 extern "C" __EXPORT int uavcan_main(int argc, char *argv[]);
@@ -637,6 +683,16 @@ int uavcan_main(int argc, char *argv[])
 		::exit(0);
 	}
 
+	if (!std::strcmp(argv[1], "arm")) {
+		inst->arm_actuators(true);
+		::exit(0);
+	}
+
+	if (!std::strcmp(argv[1], "disarm")) {
+		inst->arm_actuators(false);
+		::exit(0);
+	}
+
 	if (!std::strcmp(argv[1], "stop")) {
 		delete inst;
 		::exit(0);
diff --git a/src/modules/uavcan/uavcan_main.hpp b/src/modules/uavcan/uavcan_main.hpp
index 274321f0d..98f2e5ad4 100644
--- a/src/modules/uavcan/uavcan_main.hpp
+++ b/src/modules/uavcan/uavcan_main.hpp
@@ -42,6 +42,7 @@
 #include <uORB/topics/actuator_outputs.h>
 #include <uORB/topics/actuator_armed.h>
 #include <uORB/topics/test_motor.h>
+#include <uORB/topics/actuator_direct.h>
 
 #include "actuators/esc.hpp"
 #include "sensors/sensor_bridge.hpp"
@@ -57,6 +58,9 @@
 #define NUM_ACTUATOR_CONTROL_GROUPS_UAVCAN	4
 #define UAVCAN_DEVICE_PATH	"/dev/uavcan/esc"
 
+// we add two to allow for actuator_direct and busevent
+#define UAVCAN_NUM_POLL_FDS (NUM_ACTUATOR_CONTROL_GROUPS_UAVCAN+2)
+
 /**
  * A UAVCAN node.
  */
@@ -97,6 +101,8 @@ private:
 	int		init(uavcan::NodeID node_id);
 	void		node_spin_once();
 	int		run();
+	int		add_poll_fd(int fd);			///< add a fd to poll list, returning index into _poll_fds[]
+
 
 	int			_task = -1;			///< handle to the OS task
 	bool			_task_should_exit = false;	///< flag to indicate to tear down the CAN driver
@@ -125,6 +131,15 @@ private:
 	int			_control_subs[NUM_ACTUATOR_CONTROL_GROUPS_UAVCAN] = {};
 	actuator_controls_s 	_controls[NUM_ACTUATOR_CONTROL_GROUPS_UAVCAN] = {};
 	orb_id_t		_control_topics[NUM_ACTUATOR_CONTROL_GROUPS_UAVCAN] = {};
-	pollfd			_poll_fds[NUM_ACTUATOR_CONTROL_GROUPS_UAVCAN + 1] = {};	///< +1 for /dev/uavcan/busevent
+	pollfd			_poll_fds[UAVCAN_NUM_POLL_FDS] = {};
 	unsigned		_poll_fds_num = 0;
+
+	int			_actuator_direct_sub = -1;   ///< uORB subscription of the actuator_direct topic
+	uint8_t			_actuator_direct_poll_fd_num;
+	actuator_direct_s	_actuator_direct;
+
+	actuator_outputs_s	_outputs;
+
+	// index into _poll_fds for each _control_subs handle
+	uint8_t			_poll_ids[NUM_ACTUATOR_CONTROL_GROUPS_UAVCAN];
 };
diff --git a/src/systemcmds/motor_test/motor_test.c b/src/systemcmds/motor_test/motor_test.c
index 1b7ff75f7..77dc2f0d5 100644
--- a/src/systemcmds/motor_test/motor_test.c
+++ b/src/systemcmds/motor_test/motor_test.c
@@ -59,9 +59,10 @@ __EXPORT int motor_test_main(int argc, char *argv[]);
 static void motor_test(unsigned channel, float value);
 static void usage(const char *reason);
 
+static orb_advert_t _test_motor_pub;
+
 void motor_test(unsigned channel, float value)
 {
-	orb_advert_t        _test_motor_pub;
 	struct test_motor_s _test_motor;
 
 	_test_motor.motor_number = channel;
diff --git a/src/systemcmds/reflect/module.mk b/src/systemcmds/reflect/module.mk
new file mode 100644
index 000000000..973eb775d
--- /dev/null
+++ b/src/systemcmds/reflect/module.mk
@@ -0,0 +1,41 @@
+############################################################################
+#
+#   Copyright (c) 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.
+#
+############################################################################
+
+#
+# Dump file utility
+#
+
+MODULE_COMMAND	 = reflect
+SRCS		 = reflect.c
+
+MAXOPTIMIZATION	 = -Os
diff --git a/src/systemcmds/reflect/reflect.c b/src/systemcmds/reflect/reflect.c
new file mode 100644
index 000000000..6bb53c71a
--- /dev/null
+++ b/src/systemcmds/reflect/reflect.c
@@ -0,0 +1,111 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2014 Andrew Tridgell. 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 reflect.c
+ *
+ * simple data reflector for load testing terminals (especially USB)
+ *
+ * @author Andrew Tridgell
+ */
+
+#include <nuttx/config.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <assert.h>
+#include <systemlib/err.h>
+
+__EXPORT int reflect_main(int argc, char *argv[]);
+
+// memory corruption checking
+#define MAX_BLOCKS 1000
+static uint32_t nblocks;
+struct block {
+    uint32_t v[256];
+};
+static struct block *blocks[MAX_BLOCKS];
+
+#define VALUE(i) ((i*7) ^ 0xDEADBEEF)
+
+static void allocate_blocks(void)
+{
+    while (nblocks < MAX_BLOCKS) {
+        blocks[nblocks] = calloc(1, sizeof(struct block));
+        if (blocks[nblocks] == NULL) {
+            break;
+        }
+        for (uint32_t i=0; i<sizeof(blocks[nblocks]->v)/sizeof(uint32_t); i++) {
+            blocks[nblocks]->v[i] = VALUE(i);
+        }
+        nblocks++;
+    }
+    printf("Allocated %u blocks\n", nblocks);
+}
+
+static void check_blocks(void)
+{
+    for (uint32_t n=0; n<nblocks; n++) {
+        for (uint32_t i=0; i<sizeof(blocks[nblocks]->v)/sizeof(uint32_t); i++) {
+            assert(blocks[n]->v[i] == VALUE(i));
+        }
+    }
+}
+
+int
+reflect_main(int argc, char *argv[])
+{
+    uint32_t total = 0;
+    printf("Starting reflector\n");
+
+    allocate_blocks();
+
+    while (true) {
+        char buf[128];
+        ssize_t n = read(0, buf, sizeof(buf));
+        if (n < 0) {
+            break;
+        }
+        if (n > 0) {
+            write(1, buf, n);
+        }
+        total += n;
+        if (total > 1024000) {
+            check_blocks();
+            total = 0;
+        }
+    }
+    return OK;
+}