diff --git a/.travis.yml b/.travis.yml
index dd4e5b4401..5806f9d232 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -97,6 +97,7 @@ script:
   - cat build_posix_sitl_simple/src/modules/systemlib/mixer/mixer_multirotor.generated.h
   - echo -en 'travis_fold:end:script.2\\r'
   - echo 'Building NuttX Firmware..' && echo -en 'travis_fold:start:script.3\\r'
+  - make px4fmu-v1_default
   - make px4fmu-v2_default
   - echo -en 'travis_fold:end:script.3\\r'
   - echo 'Running Tests..' && echo -en 'travis_fold:start:script.4\\r'
diff --git a/Makefile b/Makefile
index 1e4546a3f7..2473eeff43 100644
--- a/Makefile
+++ b/Makefile
@@ -31,6 +31,14 @@
 #
 ############################################################################
 
+# Enforce the presence of the GIT repository
+#
+# We depend on our submodules, so we have to prevent attempts to
+# compile without it being present.
+ifeq ($(wildcard .git),)
+	$(error YOU HAVE TO USE GIT TO DOWNLOAD THIS REPOSITORY. ABORTING.)
+endif
+
 # Help
 # --------------------------------------------------------------------
 # Don't be afraid of this makefile, it is just passing
diff --git a/ROMFS/px4fmu_common/init.d/rc.sensors b/ROMFS/px4fmu_common/init.d/rc.sensors
index 517c77b872..08a044329f 100644
--- a/ROMFS/px4fmu_common/init.d/rc.sensors
+++ b/ROMFS/px4fmu_common/init.d/rc.sensors
@@ -112,4 +112,6 @@ fi
 
 # Wait 20 ms for sensors (because we need to wait for the HRT and work queue callbacks to fire)
 usleep 20000
-sensors start
+if sensors start
+then
+fi
diff --git a/cmake/configs/nuttx_px4fmu-v1_default.cmake b/cmake/configs/nuttx_px4fmu-v1_default.cmake
index c8a178400a..d42d5adf75 100644
--- a/cmake/configs/nuttx_px4fmu-v1_default.cmake
+++ b/cmake/configs/nuttx_px4fmu-v1_default.cmake
@@ -63,7 +63,6 @@ set(config_module_list
 	modules/navigator
 	modules/mavlink
 	modules/gpio_led
-	modules/uavcan
 	modules/land_detector
 
 	#
@@ -99,6 +98,7 @@ set(config_module_list
 	modules/controllib
 	modules/uORB
 	modules/dataman
+	modules/uavcan
 
 	#
 	# Libraries
diff --git a/nuttx-configs/px4io-v1/scripts/ld.script b/nuttx-configs/px4io-v1/scripts/ld.script
index 1a73b432c1..6cc77e9623 100755
--- a/nuttx-configs/px4io-v1/scripts/ld.script
+++ b/nuttx-configs/px4io-v1/scripts/ld.script
@@ -108,6 +108,7 @@ SECTIONS
 		*(.gnu.linkonce.d.*)
 		CONSTRUCTORS
 		_edata = ABSOLUTE(.);
+		. = ALIGN(4);
 	} > sram AT > flash
 
 	.bss : {
diff --git a/src/drivers/ms5611/ms5611_i2c.cpp b/src/drivers/ms5611/ms5611_i2c.cpp
index 86aa28a389..3a86a7f064 100644
--- a/src/drivers/ms5611/ms5611_i2c.cpp
+++ b/src/drivers/ms5611/ms5611_i2c.cpp
@@ -45,7 +45,6 @@
 #include <stdint.h>
 #include <stdbool.h>
 #include <assert.h>
-//#include <debug.h>
 #include <errno.h>
 #include <unistd.h>
 
@@ -71,20 +70,16 @@ public:
 	virtual ~MS5611_I2C();
 
 	virtual int	init();
-	virtual ssize_t	read(device::file_t *handlep, char *data, size_t count);
-	virtual int	ioctl(device::file_t *handlep, int cmd, unsigned long arg);
+	virtual int	read(unsigned offset, void *data, unsigned count);
+	virtual int	ioctl(unsigned operation, unsigned &arg);
 
-#ifdef __PX4_NUTTX
 protected:
 	virtual int	probe();
-#endif
 
 private:
 	ms5611::prom_u	&_prom;
 
-#ifdef __PX4_NUTTX
 	int		_probe_address(uint8_t address);
-#endif
 
 	/**
 	 * Send a reset command to the MS5611.
@@ -116,13 +111,7 @@ MS5611_i2c_interface(ms5611::prom_u &prom_buf, uint8_t busnum)
 }
 
 MS5611_I2C::MS5611_I2C(uint8_t bus, ms5611::prom_u &prom) :
-	I2C("MS5611_I2C",
-#ifdef __PX4_NUTTX
-	    nullptr, bus, 0, 400000
-#else
-	    "/dev/MS5611_I2C", bus, 0
-#endif
-	   ),
+	I2C("MS5611_I2C", nullptr, bus, 0, 400000),
 	_prom(prom)
 {
 }
@@ -138,8 +127,8 @@ MS5611_I2C::init()
 	return I2C::init();
 }
 
-ssize_t
-MS5611_I2C::read(device::file_t *handlep, char *data, size_t buflen)
+int
+MS5611_I2C::read(unsigned offset, void *data, unsigned count)
 {
 	union _cvt {
 		uint8_t	b[4];
@@ -163,11 +152,11 @@ MS5611_I2C::read(device::file_t *handlep, char *data, size_t buflen)
 }
 
 int
-MS5611_I2C::ioctl(device::file_t *handlep, int cmd, unsigned long arg)
+MS5611_I2C::ioctl(unsigned operation, unsigned &arg)
 {
 	int ret;
 
-	switch (cmd) {
+	switch (operation) {
 	case IOCTL_RESET:
 		ret = _reset();
 		break;
@@ -183,7 +172,6 @@ MS5611_I2C::ioctl(device::file_t *handlep, int cmd, unsigned long arg)
 	return ret;
 }
 
-#ifdef __PX4_NUTTX
 int
 MS5611_I2C::probe()
 {
@@ -220,8 +208,6 @@ MS5611_I2C::_probe_address(uint8_t address)
 
 	return PX4_OK;
 }
-#endif
-
 
 int
 MS5611_I2C::_reset()
diff --git a/src/drivers/ms5611/ms5611_nuttx.cpp b/src/drivers/ms5611/ms5611_nuttx.cpp
index 7c336dfcab..91dd785bc6 100644
--- a/src/drivers/ms5611/ms5611_nuttx.cpp
+++ b/src/drivers/ms5611/ms5611_nuttx.cpp
@@ -963,7 +963,7 @@ start(enum MS5611_BUS busid)
 			continue;
 		}
 
-		started |= start_bus(bus_options[i]);
+		started = started || start_bus(bus_options[i]);
 	}
 
 	if (!started) {
diff --git a/src/modules/mavlink/mavlink_messages.cpp b/src/modules/mavlink/mavlink_messages.cpp
index c6dde06677..fed42bef2b 100644
--- a/src/modules/mavlink/mavlink_messages.cpp
+++ b/src/modules/mavlink/mavlink_messages.cpp
@@ -556,7 +556,7 @@ protected:
 			msg.errors_count2 = status.errors_count2;
 			msg.errors_count3 = status.errors_count3;
 			msg.errors_count4 = status.errors_count4;
-			msg.battery_remaining = (msg.voltage_battery > 0) ?
+			msg.battery_remaining = (status.condition_battery_voltage_valid) ?
 							status.battery_remaining * 100.0f : -1;
 
 			_mavlink->send_message(MAVLINK_MSG_ID_SYS_STATUS, &msg);
@@ -571,14 +571,22 @@ protected:
 				if (i < status.battery_cell_count) {
 					bat_msg.voltages[i] = (status.battery_voltage / status.battery_cell_count) * 1000.0f;
 				} else {
-					bat_msg.voltages[i] = 0;
+					bat_msg.voltages[i] = UINT16_MAX;
 				}
 			}
-			bat_msg.current_battery = status.battery_current * 100.0f;
-			bat_msg.current_consumed = status.battery_discharged_mah;
+
+			if (status.condition_battery_voltage_valid) {
+				bat_msg.current_battery = (bat_msg.current_battery >= 0.0f) ?
+								status.battery_current * 100.0f : -1;
+				bat_msg.current_consumed = (bat_msg.current_consumed >= 0.0f) ?
+								status.battery_discharged_mah : -1;
+				bat_msg.battery_remaining = status.battery_remaining * 100.0f;
+			} else {
+				bat_msg.current_battery = -1.0f;
+				bat_msg.current_consumed = -1.0f;
+				bat_msg.battery_remaining = -1.0f;
+			}
 			bat_msg.energy_consumed = -1.0f;
-			bat_msg.battery_remaining = (status.battery_voltage > 0) ?
-							status.battery_remaining * 100.0f : -1;
 
 			_mavlink->send_message(MAVLINK_MSG_ID_BATTERY_STATUS, &bat_msg);
 		}
diff --git a/src/modules/sensors/sensor_params.c b/src/modules/sensors/sensor_params.c
index 06f57a26a9..1db6ed1b77 100644
--- a/src/modules/sensors/sensor_params.c
+++ b/src/modules/sensors/sensor_params.c
@@ -1810,7 +1810,6 @@ PARAM_DEFINE_INT32(BAT_V_SCALE_IO, 10000);
 /**
  * Scaling factor for battery voltage sensor on FMU v2.
  *
- * @board CONFIG_ARCH_BOARD_PX4FMU_V2
  * @group Battery Calibration
  */
 PARAM_DEFINE_FLOAT(BAT_V_SCALING, -1.0f);
diff --git a/src/modules/uavcan/uavcan_main.cpp b/src/modules/uavcan/uavcan_main.cpp
index 57bc6c1809..1ba9d345fb 100644
--- a/src/modules/uavcan/uavcan_main.cpp
+++ b/src/modules/uavcan/uavcan_main.cpp
@@ -530,8 +530,10 @@ int UavcanNode::start(uavcan::NodeID node_id, uint32_t bitrate)
 	 * If no transceiver is connected, the RX pin will float, occasionally causing CAN controller to
 	 * fail during initialization.
 	 */
+	#ifdef GPIO_CAN1_RX
 	stm32_configgpio(GPIO_CAN1_RX);
 	stm32_configgpio(GPIO_CAN1_TX);
+	#endif
 	stm32_configgpio(GPIO_CAN2_RX | GPIO_PULLUP);
 	stm32_configgpio(GPIO_CAN2_TX);