Discussions

First, I'd like to thank the team that developed and tested 2.8.1, I've recently found time to fly a more or less standard 3DR quad with APM2 and found it fly's very well  with standard parameters (the best I've flown to date).

Or it did until I flew it into a pine tree at a fair speed. Damage was light, only a bent motor mount. After fixing the motor and checking everything over I hand tested it and found that after arming I could run the motors up but when I put the throttle to "zero" the motors kept running and the quad could not be disarmed by pushing the throttle to the left, had to disconnect power. After removing the props I tested this several times, same thing.

Since the hardware seemed OK I decided to reload the firmware through Mission Planner, latest version. So I erased EEPROM, reset, rebooted (using the USB cable) and then tried to reload the firmware. When I started the firmware upload the connection to the APM2 immediately disconnected and I received a message:

"Failed to download new firmware: System, InvalidOperatinException: The port is closed, at System.IO.SerialPort.Write(Byte[buffer, Int32 offset, Int32count)......."

I repeated the erase, reset, reboot and upload firmware several times using both the USB cable and the radio link, always the same thing.

I have no trouble connecting to the APM2 to test hardware, change parameters and configure.

Any ideas, suggestions or comments would be welcome.