Significant Update and New Release - Version 4.0

Please refer to the Software update section of the Knowledge Base

(Posted here as well)


Software Version 4.0 has been restored to our servers and is now in official release.


We'd like to thank everyone for being patient while we took extensive efforts to re-validate our software for release.  This software release includes upgrades for both the HoverflyPRO and HoverflyGPS boards. Please be sure to update both boards with Version 4.0 software.



GPS Position Hold (PH)

We have spent countless hours and killed many Lipos testing and refining the performance of Position Hold.  Many of you have had great success while others have not.  The source of this inconsistency has been identified and we believe the problem has been corrected.  Position Hold now uses both the Accelerometer Calibration and the trim levels used in setting up Auto Level (AL).  We have also tightened up the control algorithm used for Position Hold.  The result is a solid Position Hold that is consistent day-to-day and craft-to-craft.  Position Hold now holds very well within the horizontal position resolution of GPS on Earth which is about 3 meters (provided adequate satellite visibility).  We are very happy with it and hope you will be as well.

GPS Slewing

Now when Position Hold is enabled you can move the craft to a new position.  The craft will fly as commanded using Auto Level flight mode.  Once the stick is centered for 1.5 seconds the craft will resume Position Hold on the new location.  You can also change the yaw during flight to rotate the craft to a new magnetic hold position.

Return-to-Home (RTH)

With improved Position Hold comes a much smoother Return-to-Home function.  Each time the board is armed a new “Home” position is recorded.  At any time during your flight Return-to-Home can be activated and the craft with return to this “Home” position (within the 3m resolution of GPS).  In addition, the speed at which the craft returns has been increased significantly.

OSD Ham Radio Call Sign or User Name

To comply with FCC regulations for transmitting video, we have added a field in the Setup Client for either your Ham Radio Call Sign or User Name to be displayed on the On-Screen-Display (OSD).  Every 10 minutes this text will be displayed where the HOVERFLY text is currently displayed for 10 seconds.

OSD Voltage

The Battery Voltage meter visible on the OSD has been rescaled to display the correct voltage.


Camera Compensation

The Tilt and Roll gimbal outputs from the HoverflyPRO have been improved to provide even smoother compensation. 

Improved Gimbal Startup

The startup errors in the gimbal have been corrected to ensure that your expensive camera gear is not jarred when arming the flight controller.

Data Logging

Several new fields have been added to the Data Log to help us diagnose any problems you may encounter during flight. In addition, each time you fly the file is appended and a new date and time stamp is inserted creating a new row in the file.

Compass Smoothing

New filtering of the compass has been applied throughout the firmware.  This improves PH, RTH, magnetic hold, and several other operations internal to the flight controller.  You will notice the improved smoothness on the compass display on the OSD.

Gyro Only Flight Performance

A few tweaks here and there and we believe Gyro only (no Auto Level) flight is drastically improved.  We have worked hard to fine tune the flight so that video, even from fixed mount cameras, appears natural like a hand held or steady-cam camera.  It was great before the change but we believe you will be amazed at how it flies now.

Fast Descent Stability

On some systems, especially with large diameter propellers, the decent of a multirotor is a difficult phase for a flight controller.  A great deal of time has been spent to improve the performance and stability during fast descents.  We understand this is important for production work with higher-end systems.  The speed of stable descent has been increased greatly.

Electronic Speed Controller (ESC) Compatibility

Some ESCs such as those made by E-Flight require 50Hz PWM during startup.  Once armed the E-Flight ESCs will accept higher PWM frequencies.  Since the HoverflyPRO uses faster than 50Hz PWM to control the motors, it was incompatible with E-Flight ESCs.  The firmware has now been modified to generate 50Hz during the arming phase and then switch to faster PWM after the ESCs are armed.  The HoverflyPRO is now fully compatible with E-Flight ESCs.



New Motor Geometries

We have added two new geometries xHex and +Octo.  We previously had +Hex and xOcto but many frames on the market utilize these new geometries.

ESC Throttle Calibration


To make setting up your aircraft easier, the HoverflyPRO now has a simple "all at once" throttle calibration procedure.  Once the transmitter is powered move the throttle stick to maximum throttle.  Power the aircraft.  Assuming your ESCs have a throttle calibration capability, you will hear the signifying beeping (specified in the ESC manual).  Move the throttle stick to minimum to store the throttle calibration.  The ESCs should now beep signifying throttle calibration has been stored.  Turn off the aircraft and then the transmitter and resume normal operation of the aircraft.

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  • 0
    steve bourne

    Great information. I am new to this and I appreciate the dedication and professionalism you show.  Thanx, steve

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