Copter-3.5.4 has been released!

Copter-3.5.4 has been released as the official version for multicopters and traditional helicopters. You should be able to download it through the Mission Planner (and other ground stations) from the Install Firmware screen.

The changes vs Copter-3.5.3 are in the ReleaseNotes.txt and also copied below:

  1. Compass improvements:
  • support added for QMC5883L, LIS3MDL, IST8310
  • COMPASS_TYPEMASK parameter allows enabling/disabling individual compass drivers
  1. LightWare and MaxBotix range finders supported on both I2C buses
  2. Serial port 5 can be used for telemetry or sensors (previously was only for NuttX console)
  3. px4pro flight controller supported
  4. TradHeli fixes:
  • motor runup check applies to all flight modes (previously only loiter, poshold, althold)
  • swashplate behaviour changes when on ground in acro, stabilize and althold
  • servo test function fixed
  • direct drive fixed pitch tail fix
  • Z-axis Accel P gain default lowered to 0.3
  1. EKF origin set using SET_GPS_GLOBAL_ORIGIN mavlink message instead of SET_HOME_POSITION
  2. Intel Aero supports 921600 baud rate between main flight controller and companion computer
  3. Bug fix to I2C race condition on Pixhawk that could occasionally cause I2C device to not be detected

Perhaps the most important change is the first one mentioned above, the additional compass driver. The popular Honeywell compass (HMC) has become nearly impossible to find so manufacturers of the Pixhawks are moving to other brands of compasses.

Thanks to our beta testers for their help getting this release out!


Thank you for your ongoing improvements :slight_smile: Telemetry on serial port 5 is great!

What is the px4pro flight controller?

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New build, Pixhawk 1 with HMC5883 external mag, can’t calibrate.
Compass 1 stays at 0%, compass 2 bar goes to 98%, success reported in the text box…

Calibration went smooth in the morning, back on 3.5.2

That would be a real shame if an issue got through the beta testing.
I wanted to ask you to go back to 3.5.3 but it seems we don’t have that immediately available through the Mission Planner’s Install Firmware screen’s “Previous Firmware” link so MichaelO will take care of that shortly.

Trying to find out the day 3.5.3 was released to get the hex from firmware repository :slight_smile:


Sep 21st it seems but it wasn’t released from master, it was released from the Copter-3.5 branch so I don’t think you’ll find a copy on the

If you could include a dataflash log (set LOG_DISARMED = 1) and/or tlog from the attempted compass calibration then we can look into it. My guess is that the BRD_TYPE parameter has been detected incorrectly or the COMPASS_TYPEMASK (which allows disabling compass drivers) is non-zero or there’s some other configuration or hardware issue.


I’ll set the log and try one more cal attempt.

LE. Nevermind me. It was a hardware issue. I’ve changed the GPS/mag and it calibrated OK.

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Telemetry on SERIAL5 is a very good news! Is it also possible to use for Frsky SPort?

Was smart RTL in this release? Nevermind sorry forgot you mentioned it was going to roll out in 3.6!!

It’s the Drotek Pixhawk 3. It’s quite a nice bump in cpu & ram compared to the stm32f427 in most pixhawk derivatives.

Ah right. It would need to be for 240euros…

Yes, Serial5 can be used for the FRSky SPort it seems. I haven’t tried it personally but it should work.

Good Randy. I will test during we

I have some problem with my pixhawk clone: I do not why but whn tring to upgrade mission planner does not recognize the board so I can only “load custom firmware”, but on the official repository latest stable 3.5.4 is not available. Where can I find it? I need to download on a quad


I found my Navio2 3.5.4 version there.

on the link you can find 3.5.4-rc2
I’m not sure this is same of stable version of 3.5.4

3.5.4 is in the “Stable” folder,


@Antonio, it’s probably an issue with the bootloader on the board not being recognised. I think MichaelOborne has a list of recognised bootloaders that the MP look at when it’s trying to decide what firmware to load. So that list just needs to be extended with the signature on the bootloader of the board you’ve got. I have no idea how to do that though.
By the way 3.5.4-rc2 and the official 3.5.4 are exactly the same except for the name.