INAV 1.6

This version has some significant differences from 1.5.1, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

INAV is and will remain open-source and free, but if you are more than welcome to support the development.

This release was supported by our awesome sponsors CarbonBird.com, Airbot and ADPM Drones.

Known bugs

• Fixed wing launch mode may fail
• Failsafe Stage 2 doesn't show as enabled in Configurator (it is always enabled, it's only UI bug)

CLI parameter renaming

Some CLI parameters are renamed to support new features or to better reflect their meaning:

Old name	New name(s)
inav_gps_min_sats	gps_min_sats
nav_alt_p	nav_mc_pos_z_p, nav_fw_pos_z_p
nav_alt_i	nav_mc_pos_z_i, nav_fw_pos_z_i
nav_alt_d	nav_mc_pos_z_d, nav_fw_pos_z_d
nav_vel_p	nav_mc_vel_z_p
nav_vel_i	nav_mc_vel_z_i
nav_vel_d	nav_mc_vel_z_d
nav_pos_p	nav_mc_pos_xy_p
nav_pos_i	nav_mc_pos_xy_i
nav_pos_d	nav_mc_pos_xy_d
nav_posr_p	nav_mc_vel_xy_p
nav_posr_i	nav_mc_vel_xy_i
nav_posr_d	nav_mc_vel_xy_d
nav_navr_p	nav_fw_pos_xy_p
nav_navr_i	nav_fw_pos_xy_i
nav_navr_d	nav_fw_pos_xy_d
servo_lowpass_freq	servo_lpf_hz
servo_lowpass_enable	Removed. To disable filtering set servo_lpf_hz to zero
acc_soft_lpf_hz	acc_lpf_hz
gyro_soft_lpf_hz	gyro_lpf_hz
gyro_lpf	gyro_hardware_lpf
rssi_ppm_invert	rssi_invert
Non-Nav Paramters (for PIFF)
p_pitch	mc_p_pitch, fw_p_pitch
i_pitch	mc_i_pitch, fw_i_pitch
d_pitch	mc_d_pitch, fw_ff_pitch
p_roll	mc_p_roll, fw_p_roll
i_roll	mc_i_roll, fw_i_roll
d_roll	mc_d_roll, fw_ff_roll
p_yaw	mc_p_yaw, fw_p_yaw
i_yaw	mc_i_yaw, fw_i_yaw
d_yaw	mc_d_yaw, fw_ff_yaw
p_level	mc_p_level, fw_p_level
i_level	mc_i_level, fw_i_level
d_level	mc_d_level, fw_d_level

Non-volatile storage for waypoint missions

As requested a lot - you now have possibility to create and upload a waypoint mission at home, go to the field, plug in the battery and fly the mission without the need to re-upload it.

Until GCS support is done you have two stick combos to do this:

Function	Throttle	Yaw	Pitch	Roll
Save current waypoint mission	LOW	CENTER	HIGH	LOW
Load current waypoint mission	LOW	CENTER	HIGH	HIGH

Mission is saved in Configuration memory and only one mission at a time can be saved. Feature is only available on F3+ targets due to lack of space on F1.

New failsafe system

Failsafe Stage 1 is completely gone now, rxfail command is deprecated. Everything that is called "FAILSAFE" is now related to actual failsafe procedure. Failsafe FEATURE is deprecated - failsafe system is always functional and ready to catch you.

New "NONE" failsafe procedure is introduced to allow completely ignoring RC link loss. Be warned that you are no longer protected from flying out of range when using this feature.

A bunch of new parameters allow "LAND" procedure to work on fixed-wing aircraft as well. Failsafe will now command a slight dive, bank and yaw to bring the airplane down nicely in case of link loss. Previous behavior was to maintain level flight and fly-away.

New parameter rx_nosignal_throttle defines how throttle channel will behave in case of link loss. Options are DROP and HOLD. Roll, Pitch and Yaw channels are centered and this behavior can't be changed anymore. This behavior is only applied for a small amount of time before FAILSAFE kicks in and starts doing something smart.

New parameter failsafe_stick_threshold will allow you to keep FAILSAFE active even if the RC link is restored. You will have to move your sticks more than failsafe_stick_threshold to regain control. This is done to allow nice return-to-home in case of signal loss. Enabled by default so in case of failsafe your craft will continue to execute failsafe procedure until you move the sticks.

New PIFF controller for fixed-wing aircraft

Introducing new Proportional + Integral + Feed Forward controller for airplanes. It's more suitable for airplanes due to the nature of control they are using. It also puts less stress on servos. D-term in Configurator will now control Feed-Forward gain which passes angular rate target directly to servos bypassing closed loop gyroscope stabilisation. Use caution - too high Feed-Forward gain may cause violent oscillations in ANGLE mode. See this article about how it is different from PID and why it is better for airplanes.

If you want direct migration from INAV 1.5 to 1.6 without using the new FF part of the controller you need to do:
Keep P-Gain as it was
Divide I-Gain by 3.5
Zero out D-Gain / FF-gain. ( So you will loose the D-gain, but this was never recommended to use. )

Airplane launch mode improvements

It's now possible to specify idle throttle for pre-launch (nav_fw_launch_idle_thr) and time to gradually increase throttle after launch is detected (nav_fw_launch_spinup_time). This allows to have motor spinning even when using MOTOR_STOP feature and will put less stress on ESCs by allowing them to spin up the motor to launch throttle gradually instead of requesting an instantenious throttle change.

Waypoint mission pre-arming check

Navigation safety checks will now include check for waypoint mission sanity. If you have a mission uploaded to FC pre-arming check will verify that first (starting) waypoint is within nav_wp_safe_distance [cm](default 10000cm = 100m) from current UAV position. If starting waypoint is too far - machine won't allow you to arm. This check can also be bypassed with nav_extra_arming_safety setting.

RTH sanity checking

Misconfigured or malfunctioning compass can confuse the firmware in such a way that it won't realize where North direction is. This may cause the machine to fly in wrong direction when i.e. doing an RTH and fly away instead of returning to home.

Another case is flying in extremely strong wind which machine is unable to fight. In such case RTH will attempt to bring machine home but will never succeed and UAV will be blown away.

RTH sanity checking feature will notice if distance to home is increasing during RTH and once amount of increase exceeds a certain threshold defined by nav_rth_abort_threshold CLI parameter instead of continuing RTH machine will enter emergency landing, self-level and go down safely. Default threshold is set to 500m which is safe enough for both multirotor machines and airplanes.

New RTH configuration options

First option is nav_rth_allow_landing (default to ON). If it's set to ON UAV will land as the last stage of RTH. Landing will function on both multirotors and airplanes (the latter will gradually descent with motors running).

Second option is nav_rth_climb_ignore_emerg (default OFF). When this option is OFF (default) and when you initiate RTH without GPS fix - aircraft will initiate emergency descent and go down. If you set this option to ON - aircraft will reach the RTH target altitude before initiating emergency descent. This is done for cases where GPS coverage is poor (i.e. in the mountains) - allowing UAV to climb up might improve GPS coverage and allow safe return instead of landing in a place where UAV might be impossible to recover.

New navigation-specific OSD indications

Now board with build-in OSD (Omnibus FC) will have indications that make it suitable for navigation:

• GPS coordinates
• Home distance and direction
• Current heading
• Climb rate (vario)

New boards

• NAZE target is split to actual NAZE and AIRHERO32 for MWC AirHero32 board
• PIXRACER board initial support. Experimental - many features are not yet functional
• OMNIBUS F4 PRO target
• F4BY target

New features

• Initial support for STM32F7 boards. More CPU power for better performance
• Full support of SoftSerial ports on F4-based boards
• Gyro/D-term notch filter and D-term setpoint weight (as in Betaflight)
• TBS Crossfire native radio protocol and telemetry (CRSF)
• Firmware support for better UI for 6-point calibration
• Make max total PID output configurable, default limit reduced to 500 for better stability
• Inversion control for S.Bus - now it's possible to have non-inverted S.Bus (for OpenLRS compatibility)
• Airplane mixers defaults to use two motor outputs now
• PASSTHRU mode will now allow to mix sticks into motors for differential thrust support
• More authority for Altitude Hold PIDs. Please revisit ALT and VEL PIDs if aircraft misbehaves.
• Two banks of PIDs for Fixed-wing and Multirotor crafts. A small step towards VTOL support
• Configurable timeout for compass calibration (instead of hard-coded 30 seconds)
• When using new Configurator the Altitude graph in Sensor tab will now show both estimated altitude and raw BARO readings
• Extremely long flights are now possible on F3/F4/F7 targets. On F1 the system time will overflow at 1 hour, 11 minutes, 35 seconds and may cause some systems to malfunction (failsafe is one of suspects). Use caution when testing this feature.
• Option to control when relative altitude is zeroed (never, on first arming, on each arming)
• New rssi_invert setting replaces rssi_ppm_invert and now also affects analog RSSI
• Blackbox logging at rates dow...

INAV 1.6-RC2

This version has some significant differences from 1.5.1, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

INAV is and will remain open-source and free, but if you are more than welcome to support the development.

This release was supported by our awesome sponsors CarbonBird.com, Airbot and ADPM Drones.

CLI parameter renaming

Some CLI parameters are renamed to support new features or to better reflect their meaning:

Old name	New name(s)
inav_gps_min_sats	gps_min_sats
nav_alt_p	nav_mc_pos_z_p, nav_fw_pos_z_p
nav_alt_i	nav_mc_pos_z_i, nav_fw_pos_z_i
nav_alt_d	nav_mc_pos_z_d, nav_fw_pos_z_d
nav_vel_p	nav_mc_vel_z_p
nav_vel_i	nav_mc_vel_z_i
nav_vel_d	nav_mc_vel_z_d
nav_pos_p	nav_mc_pos_xy_p
nav_pos_i	nav_mc_pos_xy_i
nav_pos_d	nav_mc_pos_xy_d
nav_posr_p	nav_mc_vel_xy_p
nav_posr_i	nav_mc_vel_xy_i
nav_posr_d	nav_mc_vel_xy_d
nav_navr_p	nav_fw_pos_xy_p
nav_navr_i	nav_fw_pos_xy_i
nav_navr_d	nav_fw_pos_xy_d
servo_lowpass_freq	servo_lpf_hz
servo_lowpass_enable	Removed. To disable filtering set servo_lpf_hz to zero
acc_soft_lpf_hz	acc_lpf_hz
gyro_soft_lpf_hz	gyro_lpf_hz
gyro_lpf	gyro_hardware_lpf
rssi_ppm_invert	rssi_invert
Non-Nav Paramters (for PIFF)
p_pitch	mc_p_pitch, fw_p_pitch
i_pitch	mc_i_pitch, fw_i_pitch
d_pitch	mc_d_pitch, fw_ff_pitch
p_roll	mc_p_roll, fw_p_roll
i_roll	mc_i_roll, fw_i_roll
d_roll	mc_d_roll, fw_ff_roll
p_yaw	mc_p_yaw, fw_p_yaw
i_yaw	mc_i_yaw, fw_i_yaw
d_yaw	mc_d_yaw, fw_ff_yaw
p_level	mc_p_level, fw_p_level
i_level	mc_i_level, fw_i_level
d_level	mc_d_level, fw_d_level

Non-volatile storage for waypoint missions

As requested a lot - you now have possibility to create and upload a waypoint mission at home, go to the field, plug in the battery and fly the mission without the need to re-upload it.

Until GCS support is done you have two stick combos to do this:

Function	Throttle	Yaw	Pitch	Roll
Save current waypoint mission	LOW	CENTER	HIGH	LOW
Load current waypoint mission	LOW	CENTER	HIGH	HIGH

Mission is saved in Configuration memory and only one mission at a time can be saved. Feature is only available on F3+ targets due to lack of space on F1.

New failsafe system

Failsafe Stage 1 is completely gone now, rxfail command is deprecated. Everything that is called "FAILSAFE" is now related to actual failsafe procedure. Failsafe FEATURE is deprecated - failsafe system is always functional and ready to catch you.

New "NONE" failsafe procedure is introduced to allow completely ignoring RC link loss. Be warned that you are no longer protected from flying out of range when using this feature.

A bunch of new parameters allow "LAND" procedure to work on fixed-wing aircraft as well. Failsafe will now command a slight dive, bank and yaw to bring the airplane down nicely in case of link loss. Previous behavior was to maintain level flight and fly-away.

New parameter rx_nosignal_throttle defines how throttle channel will behave in case of link loss. Options are DROP and HOLD. Roll, Pitch and Yaw channels are centered and this behavior can't be changed anymore. This behavior is only applied for a small amount of time before FAILSAFE kicks in and starts doing something smart.

New parameter failsafe_stick_threshold will allow you to keep FAILSAFE active even if the RC link is restored. You will have to move your sticks more than failsafe_stick_threshold to regain control. This is done to allow nice return-to-home in case of signal loss. Enabled by default so in case of failsafe your craft will continue to execute failsafe procedure until you move the sticks.

New PIFF controller for fixed-wing aircraft

Introducing new Proportional + Integral + Feed Forward controller for airplanes. It's more suitable for airplanes due to the nature of control they are using. It also puts less stress on servos. D-term in Configurator will now control Feed-Forward gain which passes angular rate target directly to servos bypassing closed loop gyroscope stabilisation. Use caution - too high Feed-Forward gain may cause violent oscillations in ANGLE mode. See this article about how it is different from PID and why it is better for airplanes.

Airplane launch mode improvements

It's now possible to specify idle throttle for pre-launch (nav_fw_launch_idle_thr) and time to gradually increase throttle after launch is detected (nav_fw_launch_spinup_time). This allows to have motor spinning even when using MOTOR_STOP feature and will put less stress on ESCs by allowing them to spin up the motor to launch throttle gradually instead of requesting an instantenious throttle change.

Waypoint mission pre-arming check

Navigation safety checks will now include check for waypoint mission sanity. If you have a mission uploaded to FC pre-arming check will verify that first (starting) waypoint is within nav_wp_safe_distance [cm](default 10000cm = 100m) from current UAV position. If starting waypoint is too far - machine won't allow you to arm. This check can also be bypassed with nav_extra_arming_safety setting.

RTH sanity checking

Misconfigured or malfunctioning compass can confuse the firmware in such a way that it won't realize where North direction is. This may cause the machine to fly in wrong direction when i.e. doing an RTH and fly away instead of returning to home.

Another case is flying in extremely strong wind which machine is unable to fight. In such case RTH will attempt to bring machine home but will never succeed and UAV will be blown away.

RTH sanity checking feature will notice if distance to home is increasing during RTH and once amount of increase exceeds a certain threshold defined by nav_rth_abort_threshold CLI parameter instead of continuing RTH machine will enter emergency landing, self-level and go down safely. Default threshold is set to 500m which is safe enough for both multirotor machines and airplanes.

New RTH configuration options

First option is nav_rth_allow_landing (default to ON). If it's set to ON UAV will land as the last stage of RTH. Landing will function on both multirotors and airplanes (the latter will gradually descent with motors running).

Second option is nav_rth_climb_ignore_emerg (default OFF). When this option is OFF (default) and when you initiate RTH without GPS fix - aircraft will initiate emergency descent and go down. If you set this option to ON - aircraft will reach the RTH target altitude before initiating emergency descent. This is done for cases where GPS coverage is poor (i.e. in the mountains) - allowing UAV to climb up might improve GPS coverage and allow safe return instead of landing in a place where UAV might be impossible to recover.

New navigation-specific OSD indications

Now board with build-in OSD (Omnibus FC) will have indications that make it suitable for navigation:

• GPS coordinates
• Home distance and direction
• Current heading
• Climb rate (vario)

New boards

• NAZE target is split to actual NAZE and AIRHERO32 for MWC AirHero32 board
• PIXRACER board initial support. Experimental - many features are not yet functional
• OMNIBUS F4 PRO target
• F4BY target

New features

• Initial support for STM32F7 boards. More CPU power for better performance
• Full support of SoftSerial ports on F4-based boards
• Gyro/D-term notch filter and D-term setpoint weight (as in Betaflight)
• TBS Crossfire native radio protocol and telemetry (CRSF)
• Firmware support for better UI for 6-point calibration
• Make max total PID output configurable, default limit reduced to 500 for better stability
• Inversion control for S.Bus - now it's possible to have non-inverted S.Bus (for OpenLRS compatibility)
• Airplane mixers defaults to use two motor outputs now
• PASSTHRU mode will now allow to mix sticks into motors for differential thrust support
• More authority for Altitude Hold PIDs. Please revisit ALT and VEL PIDs if aircraft misbehaves.
• Two banks of PIDs for Fixed-wing and Multirotor crafts. A small step towards VTOL support
• Configurable timeout for compass calibration (instead of hard-coded 30 seconds)
• When using new Configurator the Altitude graph in Sensor tab will now show both estimated altitude and raw BARO readings
• Extremely long flights are now possible on F3/F4/F7 targets. On F1 the system time will overflow at 1 hour, 11 minutes, 35 seconds and may cause some systems to malfunction (failsafe is one of suspects). Use caution when testing this feature.
• Option to control when relative altitude is zeroed (never, on first arming, on each arming)
• New rssi_invert setting replaces rssi_ppm_invert and now also affects analog RSSI
• Blackbox logging at rates down to 1/255 is now possible for logging long flights to onboard memory

Bugs fixed

• Telemetry and MSP data corruption on F1 (UART1 only) and F4 (all UARTs) targets
• Motor 6 output on REVO is now functional
• Occasional reboot of the board when bluetooth module is disconnected
• Rare complete stall of attitude/navigation system due to invalid gyro/acceleration data
• LED STRIP was blinking out one extra satellite when signalling GPS fix
• 3d_deadband_throttle setting was handled incorrectly by MSP which caused corruption
• iBUS telemetry not...

INAV 1.6-RC1

This version has some significant differences from 1.5.1, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

INAV is and will remain open-source and free, but if you are more than welcome to support the development.

This release was supported by our awesome sponsors CarbonBird.com, Airbot and ADPM Drones.

CLI parameter renaming

Some CLI parameters are renamed to support new features or to better reflect their meaning:

Old name	New name(s)
inav_gps_min_sats	gps_min_sats
nav_alt_p	nav_mc_pos_z_p, nav_fw_pos_z_p
nav_alt_i	nav_mc_pos_z_i, nav_fw_pos_z_i
nav_alt_d	nav_mc_pos_z_d, nav_fw_pos_z_d
nav_vel_p	nav_mc_vel_z_p
nav_vel_i	nav_mc_vel_z_i
nav_vel_d	nav_mc_vel_z_d
nav_pos_p	nav_mc_pos_xy_p
nav_pos_i	nav_mc_pos_xy_i
nav_pos_d	nav_mc_pos_xy_d
nav_posr_p	nav_mc_vel_xy_p
nav_posr_i	nav_mc_vel_xy_i
nav_posr_d	nav_mc_vel_xy_d
nav_navr_p	nav_fw_pos_xy_p
nav_navr_i	nav_fw_pos_xy_i
nav_navr_d	nav_fw_pos_xy_d
servo_lowpass_freq	servo_lpf_hz
servo_lowpass_enable	Removed. To disable filtering set servo_lpf_hz to zero
acc_soft_lpf_hz	acc_lpf_hz
gyro_soft_lpf_hz	gyro_lpf_hz
gyro_lpf	gyro_hardware_lpf
rssi_ppm_invert	rssi_invert
Non-Nav Paramters (for PIFF)
p_pitch	mc_p_pitch, fw_p_pitch
i_pitch	mc_i_pitch, fw_i_pitch
d_pitch	mc_d_pitch, fw_ff_pitch
p_roll	mc_p_roll, fw_p_roll
i_roll	mc_i_roll, fw_i_roll
d_roll	mc_d_roll, fw_ff_roll
p_yaw	mc_p_yaw, fw_p_yaw
i_yaw	mc_i_yaw, fw_i_yaw
d_yaw	mc_d_yaw, fw_ff_yaw
p_level	mc_p_level, fw_p_level
i_level	mc_i_level, fw_i_level
d_level	mc_d_level, fw_d_level

Non-volatile storage for waypoint missions

As requested a lot - you now have possibility to create and upload a waypoint mission at home, go to the field, plug in the battery and fly the mission without the need to re-upload it.

This function is available in the mwp CGS, otherwise you have two stick combos to do this:

Function	Throttle	Yaw	Pitch	Roll
Save current waypoint mission	LOW	CENTER	HIGH	LOW
Load current waypoint mission	LOW	CENTER	HIGH	HIGH

Mission is saved in Configuration memory and only one mission at a time can be saved. Feature is only available on F3+ targets due to lack of space on F1.

New failsafe system

Failsafe Stage 1 is completely gone now, rxfail command is deprecated. Everything that is called "FAILSAFE" is now related to actual failsafe procedure. Failsafe FEATURE is deprecated - failsafe system is always functional and ready to catch you.

New "NONE" failsafe procedure is introduced to allow completely ignoring RC link loss. Be warned that you are no longer protected from flying out of range when using this feature.

A bunch of new parameters allow "LAND" procedure to work on fixed-wing aircraft as well. Failsafe will now command a slight dive, bank and yaw to bring the airplane down nicely in case of link loss. Previous behavior was to maintain level flight and fly-away.

New parameter rx_nosignal_throttle defines how throttle channel will behave in case of link loss. Options are DROP and HOLD. Roll, Pitch and Yaw channels are centered and this behavior can't be changed anymore. This behavior is only applied for a small amount of time before FAILSAFE kicks in and starts doing something smart.

New parameter failsafe_stick_threshold will allow you to keep FAILSAFE active even if the RC link is restored. You will have to move your sticks more than failsafe_stick_threshold to regain control. This is done to allow nice return-to-home in case of signal loss. Enabled by default so in case of failsafe your craft will continue to execute failsafe procedure until you move the sticks.

New PIFF controller for fixed-wing aircraft

Introducing new Proportional + Integral + Feed Forward controller for airplanes. It's more suitable for airplanes due to the nature of control they are using. It also puts less stress on servos. D-term in Configurator will now control Feed-Forward gain which passes angular rate target directly to servos bypassing closed loop gyroscope stabilisation. Use caution - too high Feed-Forward gain may cause violent oscillations in ANGLE mode. See this article about how it is different from PID and why it is better for airplanes.

Airplane launch mode improvements

It's now possible to specify idle throttle for pre-launch (nav_fw_launch_idle_thr) and time to gradually increase throttle after launch is detected (nav_fw_launch_spinup_time). This allows to have motor spinning even when using MOTOR_STOP feature and will put less stress on ESCs by allowing them to spin up the motor to launch throttle gradually instead of requesting an instantenious throttle change.

Waypoint mission pre-arming check

Navigation safety checks will now include check for waypoint mission sanity. If you have a mission uploaded to FC pre-arming check will verify that first (starting) waypoint is within nav_wp_safe_distance [cm](default 10000cm = 100m) from current UAV position. If starting waypoint is too far - machine won't allow you to arm. This check can also be bypassed with nav_extra_arming_safety setting.

RTH sanity checking

Misconfigured or malfunctioning compass can confuse the firmware in such a way that it won't realize where North direction is. This may cause the machine to fly in wrong direction when i.e. doing an RTH and fly away instead of returning to home.

Another case is flying in extremely strong wind which machine is unable to fight. In such case RTH will attempt to bring machine home but will never succeed and UAV will be blown away.

RTH sanity checking feature will notice if distance to home is increasing during RTH and once amount of increase exceeds a certain threshold defined by nav_rth_abort_threshold CLI parameter instead of continuing RTH machine will enter emergency landing, self-level and go down safely. Default threshold is set to 500m which is safe enough for both multirotor machines and airplanes.

New RTH configuration options

First option is nav_rth_allow_landing (default to ON). If it's set to ON UAV will land as the last stage of RTH. Landing will function on both multirotors and airplanes (the latter will gradually descent with motors running).

Second option is nav_rth_climb_ignore_emerg (default OFF). When this option is OFF (default) and when you initiate RTH without GPS fix - aircraft will initiate emergency descent and go down. If you set this option to ON - aircraft will reach the RTH target altitude before initiating emergency descent. This is done for cases where GPS coverage is poor (i.e. in the mountains) - allowing UAV to climb up might improve GPS coverage and allow safe return instead of landing in a place where UAV might be impossible to recover.

New boards

• NAZE target is split to actual NAZE and AIRHERO32 for MWC AirHero32 board
• PIXRACER board initial support. Experimental - many features are not yet functional
• OMNIBUS F4 PRO target
• F4BY target

New features

• Initial support for STM32F7 boards. More CPU power for better performance
• Full support of SoftSerial ports on F4-based boards
• Gyro/D-term notch filter and D-term setpoint weight (as in Betaflight)
• TBS Crossfire native radio protocol and telemetry (CRSF)
• Firmware support for better UI for 6-point calibration
• Make max total PID output configurable, default limit reduced to 500 for better stability
• Inversion control for S.Bus - now it's possible to have non-inverted S.Bus (for OpenLRS compatibility)
• Airplane mixers defaults to use two motor outputs now
• PASSTHRU mode will now allow to mix sticks into motors for differential thrust support
• More authority for Altitude Hold PIDs. Please revisit ALT and VEL PIDs if aircraft misbehaves.
• Two banks of PIDs for Fixed-wing and Multirotor crafts. A small step towards VTOL support
• Configurable timeout for compass calibration (instead of hard-coded 30 seconds)
• When using new Configurator the Altitude graph in Sensor tab will now show both estimated altitude and raw BARO readings
• Extremely long flights are now possible on F3/F4/F7 targets. On F1 the system time will overflow at 1 hour, 11 minutes, 35 seconds and may cause some systems to malfunction (failsafe is one of suspects). Use caution when testing this feature.
• Option to control when relative altitude is zeroed (never, on first arming, on each arming)
• New rssi_invert setting replaces rssi_ppm_invert and now also affects analog RSSI
• Blackbox logging at rates down to 1/255 is now possible for logging long flights to onboard memory
• More indications on OSD for supported targets - GPS coordinates, distance and direction to home
• 'pseudo' RSSI for Spektrum satellites (from fade count, as Betaflight)
• Profiles in the CLI are now numbered 1-3 for compatibility with the configurator; be aware if restoring settings from CLI dump.

Bugs fixed

• Telemetry and MSP data corruption on F1 (UART1 only) and F4 (all UARTs) targets
• Motor 6 output on REVO is now functional
• Occasional reboot of the board when bluetooth module is disconnected
• Rare complete stall of attitude/navigation system due to invalid gyro/acceleration data
• LED STRIP was blinking...

INAV 1.6-ALPHA2

This is an ALPHA release. Use caution!

This version has some significant differences from 1.5.1, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

CLI parameter renaming

Some CLI parameters are renamed to support new features or to better reflect their meaning:

Old name	New name(s)
inav_gps_min_sats	gps_min_sats
nav_alt_p	nav_mc_pos_z_p, nav_fw_pos_z_p
nav_alt_i	nav_mc_pos_z_i, nav_fw_pos_z_i
nav_alt_d	nav_mc_pos_z_d, nav_fw_pos_z_d
nav_vel_p	nav_mc_vel_z_p
nav_vel_i	nav_mc_vel_z_i
nav_vel_d	nav_mc_vel_z_d
nav_pos_p	nav_mc_pos_xy_p
nav_pos_i	nav_mc_pos_xy_i
nav_pos_d	nav_mc_pos_xy_d
nav_posr_p	nav_mc_vel_xy_p
nav_posr_i	nav_mc_vel_xy_i
nav_posr_d	nav_mc_vel_xy_d
nav_navr_p	nav_fw_pos_xy_p
nav_navr_i	nav_fw_pos_xy_i
nav_navr_d	nav_fw_pos_xy_d
servo_lowpass_freq	servo_lpf_hz
servo_lowpass_enable	Removed. To disable filtering set servo_lpf_hz to zero
acc_soft_lpf_hz	acc_lpf_hz
gyro_soft_lpf_hz	gyro_lpf_hz
gyro_lpf	gyro_hardware_lpf
rssi_ppm_invert	rssi_invert
Non-Nav Paramters (for PIFF)
p_pitch	mc_p_pitch, fw_p_pitch
i_pitch	mc_i_pitch, fw_i_pitch
d_pitch	mc_d_pitch, fw_d_pitch
p_roll	mc_p_roll, fw_p_roll
i_roll	mc_i_roll, fw_i_roll
d_roll	mc_d_roll, fw_d_roll
p_yaw	mc_p_yaw, fw_p_yaw
i_yaw	mc_i_yaw, fw_i_yaw
d_yaw	mc_d_yaw, fw_d_yaw
p_level	mc_p_level, fw_p_level
i_level	mc_i_level, fw_i_level
d_level	mc_d_level, fw_d_level

New failsafe system

Failsafe Stage 1 is completely gone now, rxfail command is deprecated. Everything that is called "FAILSAFE" is now related to actual failsafe procedure. Failsafe FEATURE is deprecated - failsafe system is always functional and ready to catch you.

New "NONE" failsafe procedure is introduced to allow completely ignoring RC link loss. Be warned that you are no longer protected from flying out of range when using this feature.

A bunch of new parameters allow "LAND" procedure to work on fixed-wing aircraft as well. Failsafe will now command a slight dive, bank and yaw to bring the airplane down nicely in case of link loss. Previous behavior was to maintain level flight and fly-away.

New parameter rx_nosignal_throttle defines how throttle channel will behave in case of link loss. Options are DROP and HOLD. Roll, Pitch and Yaw channels are centered and this behavior can't be changed anymore. This behavior is only applied for a small amount of time before FAILSAFE kicks in and starts doing something smart.

New parameter failsafe_stick_threshold will allow you to keep FAILSAFE active even if the RC link is restored. You will have to move your sticks more than failsafe_stick_threshold to regain control. This is done to allow nice return-to-home in case of signal loss.

New PIFF controller for fixed-wing aircraft

Introducing new Proportional + Integral + Feed Forward controller for airplanes. It's more suitable for airplanes due to the nature of control they are using. It also puts less stress on servos. D-term in Configurator will now control Feed-Forward gain which passes angular rate target directly to servos bypassing closed loop gyroscope stabilisation. Use caution - too high Feed-Forward gain may cause violent oscillations in ANGLE mode.

Airplane launch mode improvements

It's now possible to specify idle throttle for pre-launch (nav_fw_launch_idle_thr) and time to gradually increase throttle after launch is detected (nav_fw_launch_spinup_time). This allows to have motor spinning even when using MOTOR_STOP feature and will put less stress on ESCs by allowing them to spin up the motor to launch throttle gradually instead of requesting an instantenious throttle change.

Waypoint mission pre-arming check

Navigation safety checks will now include check for waypoint mission sanity. If you have a mission uploaded to FC pre-arming check will verify that first (starting) waypoint is within nav_wp_safe_distance [cm](default 10000cm = 100m) from current UAV position. If starting waypoint is too far - machine won't allow you to arm. This check can also be bypassed with nav_extra_arming_safety setting.

RTH sanity checking

Misconfigured or malfunctioning compass can confuse the firmware in such a way that it won't realize where North direction is. This may cause the machine to fly in wrong direction when i.e. doing an RTH and fly away instead of returning to home.

Another case is flying in extremely strong wind which machine is unable to fight. In such case RTH will attempt to bring machine home but will never succeed and UAV will be blown away.

RTH sanity checking feature will notice if distance to home is increasing during RTH and once amount of increase exceeds a certain threshold defined by nav_rth_abort_threshold CLI parameter instead of continuing RTH machine will enter emergency landing, self-level and go down safely. Default threshold is set to 500m which is safe enough for both multirotor machines and airplanes.

New RTH configuration options

First option is nav_rth_allow_landing (default to ON). If it's set to ON UAV will land as the last stage of RTH. Landing will function on both multirotors and airplanes (the latter will gradually descent with motors running).

Second option is nav_rth_climb_ignore_emerg (default OFF). When this option is OFF (default) and when you initiate RTH without GPS fix - aircraft will initiate emergency descent and go down. If you set this option to ON - aircraft will reach the RTH target altitude before initiating emergency descent. This is done for cases where GPS coverage is poor (i.e. in the mountains) - allowing UAV to climb up might improve GPS coverage and allow safe return instead of landing in a place where UAV might be impossible to recover.

New boards

• NAZE target is split to actual NAZE and AIRHERO32 for MWC AirHero32 board
• PIXRACER board initial support. Experimental - many features are not yet functional
• OMNIBUS F4 SD target
• F4BY target

New features

• Initial support for STM32F7 boards. More CPU power for better performance
• Full support of SoftSerial ports on F4-based boards
• Gyro/D-term notch filter and D-term setpoint weight (as in Betaflight)
• TBS Crossfire native radio protocol and telemetry (CRSF)
• Firmware support for better UI for 6-point calibration
• Make max total PID output configurable, default limit reduced to 500 for better stability
• Inversion control for S.Bus - now it's possible to have non-inverted S.Bus (for OpenLRS compatibility)
• Airplane mixers defaults to use two motor outputs now
• PASSTHRU mode will now allow to mix sticks into motors for differential thrust support
• More authority for Altitude Hold PIDs. Please revisit ALT and VEL PIDs if aircraft misbehaves.
• Two banks of PIDs for Fixed-wing and Multirotor crafts. A small step towards VTOL support
• Configurable timeout for compass calibration (instead of hard-coded 30 seconds)
• When using new Configurator the Altitude graph in Sensor tab will now show both estimated altitude and raw BARO readings
• Extremely long flights are now possible on F3/F4/F7 targets. On F1 the system time will overflow at 1 hour, 11 minutes, 35 seconds and may cause some systems to malfunction (failsafe is one of suspects). Use caution when testing this feature.
• Option to control when relative altitude is zeroed (never, on first arming, on each arming)
• New rssi_invert setting replaces rssi_ppm_invert and now also affects analog RSSI

Bugs fixed

• Telemetry and MSP data corruption on F1 (UART1 only) and F4 (all UARTs) targets
• Motor 6 output on REVO is now functional
• Occasional reboot of the board when bluetooth module is disconnected
• Rare complete stall of attitude/navigation system due to invalid gyro/acceleration data
• LED STRIP was blinking out one extra satellite when signalling GPS fix
• 3d_deadband_throttle setting was handled incorrectly by MSP which caused corruption
• iBUS telemetry not functional bug
• Temporary fix for a Sparky 2 compass bug

INAV 1.6-ALPHA1

This is an ALPHA release. Use caution!

This version has some significant differences from 1.5.1, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

CLI parameter renaming

Some CLI parameters are renamed to support new features or to better reflect their meaning:

Old name	New name(s)
nav_alt_p	nav_mc_pos_z_p, nav_fw_pos_z_p
nav_alt_i	nav_mc_pos_z_i, nav_fw_pos_z_i
nav_alt_d	nav_mc_pos_z_d, nav_fw_pos_z_d
nav_vel_p	nav_mc_vel_z_p
nav_vel_i	nav_mc_vel_z_i
nav_vel_d	nav_mc_vel_z_d
nav_pos_p	nav_mc_pos_xy_p
nav_pos_i	nav_mc_pos_xy_i
nav_pos_d	nav_mc_pos_xy_d
nav_posr_p	nav_mc_vel_xy_p
nav_posr_i	nav_mc_vel_xy_i
nav_posr_d	nav_mc_vel_xy_d
nav_navr_p	nav_fw_pos_xy_p
nav_navr_i	nav_fw_pos_xy_i
nav_navr_d	nav_fw_pos_xy_d
servo_lowpass_freq	servo_lpf_hz
servo_lowpass_enable	Removed. To disable filtering set servo_lpf_hz to zero
acc_soft_lpf_hz	acc_lpf_hz
gyro_soft_lpf_hz	gyro_lpf_hz
gyro_lpf	gyro_hardware_lpf
Non-Nav Paramters (for PIFF)
p_pitch	mc_p_pitch, fw_p_pitch
i_pitch	mc_i_pitch, fw_i_pitch
d_pitch	mc_d_pitch, fw_d_pitch
p_roll	mc_p_roll, fw_p_roll
i_roll	mc_i_roll, fw_i_roll
d_roll	mc_d_roll, fw_d_roll
p_yaw	mc_p_yaw, fw_p_yaw
i_yaw	mc_i_yaw, fw_i_yaw
d_yaw	mc_d_yaw, fw_d_yaw
p_level	mc_p_level, fw_p_level
i_level	mc_i_level, fw_i_level
d_level	mc_d_level, fw_d_level

New failsafe system

Failsafe Stage 1 is completely gone now, rxfail command is deprecated. Everything that is called "FAILSAFE" is now related to actual failsafe procedure. Failsafe FEATURE is deprecated - failsafe system is always functional and ready to catch you.

New "NONE" failsafe procedure is introduced to allow completely ignoring RC link loss. Be warned that you are no longer protected from flying out of range when using this feature.

A bunch of new parameters allow "LAND" procedure to work on fixed-wing aircraft as well. Failsafe will now command a slight dive, bank and yaw to bring the airplane down nicely in case of link loss. Previous behavior was to maintain level flight and fly-away.

New parameter rx_nosignal_throttle defines how throttle channel will behave in case of link loss. Options are DROP and HOLD. Roll, Pitch and Yaw channels are centered and this behavior can't be changed anymore. This behavior is only applied for a small amount of time before FAILSAFE kicks in and starts doing something smart.

New parameter failsafe_stick_threshold will allow you to keep FAILSAFE active even if the RC link is restored. You will have to move your sticks more than failsafe_stick_threshold to regain control. This is done to allow nice return-to-home in case of signal loss.

New PIFF controller for fixed-wing aircraft

Introducing new Proportional + Integral + Feed Forward controller for airplanes. It's more suitable for airplanes due to the nature of control they are using. It also puts less stress on servos. D-term in Configurator will now control Feed-Forward gain which passes angular rate target directly to servos bypassing closed loop gyroscope stabilisation. Use caution - too high Feed-Forward gain may cause violent oscillations in ANGLE mode.

Airplane launch mode improvements

It's now possible to specify idle throttle for pre-launch (nav_fw_launch_idle_thr) and time to gradually increase throttle after launch is detected (nav_fw_launch_spinup_time). This allows to have motor spinning even when using MOTOR_STOP feature and will put less stress on ESCs by allowing them to spin up the motor to launch throttle gradually instead of requesting an instantenious throttle change.

RTH sanity checking

Misconfigured or malfunctioning compass can confuse the firmware in such a way that it won't realize where North direction is. This may cause the machine to fly in wrong direction when i.e. doing an RTH and fly away instead of returning to home.

Another case is flying in extremely strong wind which machine is unable to fight. In such case RTH will attempt to bring machine home but will never succeed and UAV will be blown away.

RTH sanity checking feature will notice if distance to home is increasing during RTH and once amount of increase exceeds a certain threshold defined by nav_rth_abort_threshold CLI parameter instead of continuing RTH machine will enter emergency landing, self-level and go down safely. Default threshold is set to 500m which is safe enough for both multirotor machines and airplanes.

New boards

• NAZE target is split to actual NAZE and AIRHERO32 for MWC AirHero32 board
• PIXRACER board initial support. Experimental - many features are not yet functional
• OMNIBUS F4 SD target
• F4BY target

New features

• Initial support for STM32F7 boards. More CPU power for better performance
• Full support of SoftSerial ports on F4-based boards
• Gyro/D-term notch filter and D-term setpoint weight (as in Betaflight)
• TBS Crossfire native radio protocol and telemetry (CRSF)
• Firmware support for better UI for 6-point calibration
• Make max total PID output configurable, default limit reduced to 500 for better stability
• Inversion control for S.Bus - now it's possible to have non-inverted S.Bus (for OpenLRS compatibility)
• Airplane mixers defaults to use two motor outputs now
• PASSTHRU mode will now allow to mix sticks into motors for differential thrust support
• More authority for Altitude Hold PIDs. Please revisit ALT and VEL PIDs if aircraft misbehaves.
• Two banks of PIDs for Fixed-wing and Multirotor crafts. A small step towards VTOL support
• Configurable timeout for compass calibration (instead of hard-coded 30 seconds)
• When using new Configurator the Altitude graph in Sensor tab will now show both estimated altitude and raw BARO readings
• Extremely long flights are now possible on F3/F4/F7 targets. On F1 the system time will overflow at 1 hour, 11 minutes, 35 seconds and may cause some systems to malfunction (failsafe is one of suspects). Use caution when testing this feature.

Bugs fixed

• Telemetry and MSP data corruption on F1 (UART1 only) and F4 (all UARTs) targets
• Motor 6 output on REVO is now functional
• Occasional reboot of the board when bluetooth module is disconnected
• Rare complete stall of attitude/navigation system due to invalid gyro/acceleration data
• LED STRIP was blinking out one extra satellite when signalling GPS fix
• 3d_deadband_throttle setting was handled incorrectly by MSP which caused corruption
• iBUS telemetry not functional bug

INAV 1.5.1

This is a release to fix some serious bugs in INAV-1.5 that were discovered too late to make it into that release.

As usual, you are encouraged to upgrade INAV Configurator available at Chrome Store.

INAV is and will remain open-source and free, but if you are more than welcome to support the development.

Bugfixes

• Fix a buffer overflow in I2C driver (affecting only COLIBRI/QUANTON target)
• Fix a bug with failsafe_recovery_timeout being reset to arbitrary value
• Fix corrupt blackbox logs and hickups in MSP on F1/F4 targets
• CC3D target M3 disabled bug

Happy flying!

INAV 1.5

This version has some significant differences from 1.4, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

INAV is and will remain open-source and free, but if you are more than welcome to support the development.

This release was supported by our awesome sponsors CarbonBird.com, Airbot and Ledge team.

Sensor hardware configuration is now mandatory

For better robustness sensor autodetection is no longer done each boot. Instead user should explicitly configure sensor hardware on Configuration tab. User still may chose AUTO, on first boot firmware will perform autodetection and switch to first detected sensor (if any).

Hardware failure detection & arming prevention

INAV now tests if all configured sensors are available and won't allow you to arm if any of the following is true:

• CPU is overloaded
• UAV not level (aka small_angle)
• Run-time sensor calibration is not finished (covers GYRO and BARO)
• One of the sensors is configured, but not detected or not working properly
• Compass sensor is present, but not calibrated
• Accelerometer is present, but not calibrated
• Navigation is unsafe (no GPS lock, aka nav_extra_arming_safety)

Hardware failure is indicated by LED_STRIP (blue/black pattern) or beeper (fast beeps).

OSD support

Targets with onboard OSD now work properly. This is a direct port of Betaflight code and not all of the required information is displayed yet (i.e. no GPS coordinates), but that's a work in progress.

Target/feature support

• New target - QUANTON/COLIBRI
• CC3D_OPBL is no longer supported due to memory limitation

More new features and improvements

• Used tightly-coupled memory on CPUs that support it (it's an area of memory that is faster than common RAM, it also frees up common RAM for other tasks)
• New target - COLIBRI/QUANTON
• Fix missing consumed mAh reporting in LTM telemetry
• Completely new I2C driver stack - more robust, less prone to errors
• Option to specify time of good RC link for switching out from Stage 2 failsafe
• It's now possible to specify if RTH should fly home right away or reach the safe altitude first (see nav_rth_climb_first CLI parameter)
• Launching a flying wing by throwing it by the wing-tip (known as swing-launch in INAV) is now correctly detected by launch assistant
• CLI now uses sensor names instead of numbers for acc_hardware, mag_hardware etc
• Servo autotrim feature for airplanes - ability to calculate and record servo neutral position when flying in stabilised modes
• SoftSerial is now supported on AIRBOTF4 target
• Moved PPM input to pin 3 of RC connector on AIRHEROF3 target to keep compatibilty with Betaflight and earler setups

Bugfixes

• Occasional non-detection of built-in SPRacingF3 EVO compass
• Initial work done to solve the time overflow occurring at 72nd minute of operation. Issue is not completely solved yet.
• Fix a bug with coarse stick resolution in ACRO mode resulting in inability to make fine corrections (known as "deadband even when deadband = 0 issue")
• Fix UART3/I2C sharing issues on some targets
• Fix non-working UART5 on targets that support it
• Baro and GPS co-existance issue is now completely solved - baro is preferred when available
• Fix bug that allowed the MSP-aware OSD or GCS to reboot the flight controller in flight
• Tricopter mix made functional on AIRBOTF4 and OMNIBUS
• Failsafe stage 1 now defaults to "hold" on throttle channel to suite INAV better
• Fix documentation for AIRHEROF3 target
• Fix bug in PWM receiver code that may cause failse failsafe triggering
• Fix a bug that caused failsafe Stage 1 "hold" values to be ignored on flight channels if Stage 2 is disabled
• Bugfix for possible arming directly into Stage 2 failsafe procedure
• Fix buffer overflow in VCP driver that may cause corrupt blackbox downloads
• Fix a bug that allowed HOME position to be altered by MSP command in flight without explicit permission from pilot
• Lots of smaller bugfixes

Known bugs

• CC3D target doesn't work

Thanks to all who participated in improving the code and put their vehicles at risk testing new features!

Happy New Year to all pilots!
Fly safe!

INAV 1.4

INAV v1.4

This version has some significant differences from 1.3, please read the release notes carefully and upgrade INAV Configurator available at Chrome Store.

Motor/servo outputs are DISABLED by default

For safety motor/servo outputs are disabled after flashing with config erase. After configuring motor/servo mixer you have to enable PWM outputs using CLI (feature PWM_OUTPUT_ENABLE) or using new Configurator.

CC3D/NAZE target space issues

To keep CC3D/NAZE targets working with all bells and whistles we had to remove support for some SerialRX protocols that are not widely used. S.Bus, I-Bus and Spektrum are still supported on all targets.

Also Frsky telemetry had to be removed from F1 targets.

Asynchronous gyro/PID processing

It has been shown that it's possible to sample gyro at higher rate and process it at much lower rate without noticable impact on flight performance. In ACRO only it's now possible to do 8kHz gyro updates on some targets. Even better racing performance now.

Airplane improvements

• INAV 1.4 features new airplane launch assistant as well as new TPA for airplanes. Have a look at the wiki to see how to tune new TPA (https://github.com/iNavFlight/inav/wiki/PID-Attenuation-and-scaling). And for details of iNav launch https://github.com/iNavFlight/inav/wiki/8.-Navigation-modes#launch---airplane-launch-assistant
• Experimental emergency landing is available to land the aircraft in a very unfortunate event of GPS loss when executing RTH or WP mission.
• Basic pitot airspeed sensor support (logging purposes only, stay tuned for airspeed control in 1.5)

Significantly reworked position estimation code

• It now handles GPS+BARO better on ariplanes and recovers better from GPS outages. More safety for your aircraft when in automatic modes.
• Better handling GPS+MAG on airplanes - now it is safe to keep MAG enabled on airplane if required. GPS heading is preferred with fallback on MAG if speed is too low or GPS heading error is too big. Note, that if you have compass close to power wires or magnetic objects it's safer to keep it disabled.
• Better handling of pilot-engaged RTH and failsafe RTH.
• Prioir to first ARMing altitude is forced to be zero to ensure that altitude is indeed measured above HOME. This is normal and doesn't indicate baro/GPS problems.

More supported targets

• Airbot F4 / FLIP32 F4
• Omnibus F4 (w/o OSD)
• YuPiF4 board initial support

Switch settings

Please check that your switch / mode settings are as intended. Copying a 1.3 CLI dump aux settings may not give the desired results.

Bugfixes

• Failsafe is now safer, no more disarming in the air when loosing RC link at zero throttle.
• Fixes for sensor detection, now INAV will retry sensor detection up to 5 times before reporting it missing.
• Fix broken I2C on AirHeroF3 target (AIRHEROF3_QUAD flavour)
• Fixed issue with baro on fixed-wing.
• Fixed PID profile count on F1 targets
• Lots of code cleanups and smaller improvements

Thanks to all who participated in improving the code and put their vehicles at risk testing new features! You guys are awesome!

If you like INAV, please conisder supporting the development. This release was supported by our awesome sponsors CarbonBird.com, Airbot and Ledge team.

Thanks and happy flying!

INAV 1.3

I'm happy to announce INAV 1.3!

Most notable change is always unsynched motor updates. At over 1-2 kHz update rate the delay between PID loop and motor update is negligible (at 1 kHz average delay would be 0.5ms which is merely ~2% of total quad response delay).

Please update INAV Configurator from Chrome Store.

WARNING

FEATURE_ONESHOT125 is now deprecated, you will have to select appropriate motor_pwm_protocol and motor_pwm_rate via CLI to specify ESC protocol and update rate. I.e. for OS125@2kHz you'll have to set:

set motor_pwm_protocol = ONESHOT125
set motor_pwm_rate = 2000

This firmware also supports ONESHOT42 and MULTISHOT ESC protocols.

WARNING

Flight mode IDs have changed in CLI. When restoring old CLI dumps please verify that Flight modes are assigned correctly.

New targets

• OMNIBUS FC initial support (w/o OSD)
• MultiWiiCopter AIRHEROF3 FC
• SPRacingF3 MINI (w/o race transponder)

New features

• FlySky I-Bus telemetry
• PCA9685 PWM driver to provide lots of servo outputs for airplanes
• Possibility to have airplanes auto-arm on throttle up (and never disarm)
• Stack usage detection
• Removed unused/deprecated box modes (GOV, LEDMAX, CAMTRIG, SERVO1-3)

Bugfixes

• Fixed MAG mode aligning the machine North when enabled from the beginning
• Additional I-term limits for airplanes to prevent wind up when launching
• Improvements to INAV nRF24 protocol
• I2C error handling fix - solves most compass detection issues
• I2C timeout fix (BMP280/BMP085 initialisation fix)
• AK8963 compass (part of MPU9250) fix
• BMP280 update rate fix
• Lots of code cleanups

Thanks to @DzikuVx, @stronnag, @martinbudden, @sambas, @oleost and others who participated in INAV in any way and to all those who put their flying machines at risk testing the code.

Happy flying!

INAV 1.2.1

This is a bugfix release:

• Fix incorrect BMP280 read scheduling. Solves issue with random compass readings on some machines.
• Fix for HORIZON mode when with certain settings self-leveling was never disabled completely.

Thanks to all who helped tracking down these bugs.