"It is good to have a Ftdi serial connection to be able to see the startup msgs on the console.   You can also avoid the Usb and move the mavlink connection to serial port instead of Usb.   It would be good to have a startup  script that can be…"

"It Is very odd  the behaviour of the usb  mavlink.   The usb port is created in the px4 software but serial data is not being sent
On top of this windows usb will get jamed up and will not connect to the port  after it is unpluged while a program…"

"I  disconected the GPS and everything else from the FMU and found the mavlink port did not start sending  when   plugging in to the usb if  the Fmu  had been disconnected for about  10- 15 min.  Leaving the Fmu  connected to usb for 10- 20  min and…"

"With  Fmu   the  only arming is the regular right yaw stick command.
 "

"Tristan ,  I have problems with the mavlink  starting as well.   What I have found is that  monitoring the console on serial 1  it will start  if i enter  a return on the console after the start up script has run.   I have been  jumpering the tx/rx…"

"Has anyone tried the native px4   FW  with the  hex or octo  mixers .
https://github.com/PX4/Firmware/blob/master/ROMFS/mixers/README
Like This   one for  hex
"This file defines a single mixer for a hexacopter in the X configuration.  All controls…"

"At this time with the 2.91b-dev  on startup  the Virtual com port on the USB is being created  but the ArduCopter task gets hung up.  If a  ftdi serial is connected to the console port  sending a return  allows it to boot up  and start mavlink on…"

"Angelo  I love the response  you got here .   Your thread is at the top of the list when I searced the forum. Some info has come out lately and their is a .px4 binary  that has the arducopter  single threaded task in the build .…"

"I  had not looked at  Areoquad  for a while  and I see  Areoquad32  software has these sensors confiureable  and MPU6000 interface selectable  as I2c or Spi   , wouldn't  that be great on arducopter !
So it looks like the next project will be…"

"Most of the reports of freezing  during connect have been the sensor init failing in the background .
Check for error during boot in the Terminal screen and test the sensors in cli
 "

"You can log and graph the output to the ESC in the log with the motors  log.  This would tell you if  the  esc calibration was off.    The  system  controls Yaw by varying the CW and counter Cw  motor  speed , setting the yaw pid to zero removes …"

"Yes you can use the  telemetry serial  0 port at 57600 baud to connect to mission planner and to upload sketch from auduino.
 The  auto reset function  will be missing so you have to use reset button  to upload  sketch and connect 5V  from Ftdi or…"

"With the Usb connector on my APM2  trashed  I will have to pull the board and solder the isp header to update the PPM encoder. 
Are all Futaba radios  seeing the glitches?  The discussion had reference to some receivers  not displaying the problem.…"