Odd behavior from MP 1.2.85

I am running a home-built quadcopter using APM2.5 and the 3.0.1 firmware.

I just upgraded to Mission Planner 1.2.85 and I am having issues with the connection.  Every time I have my APM 2.5 running on USB (all lights on or flashing), and I try to connect from Mission Planner, my GPS and Arm/Safe leds go off and the Mission Planner never connects.

I've tried several different USB cords, and several different configurations.  Initially I thought that my RC receiver may have been pulling too much current, but the APM responds in the same way even when it has no inputs connected.  I also was unable to connect when the APM was powered from the LiPo and connected with USB, so I don't think power is the problem.

A few times I have been connected when the leds came back on before MP timed out.  In these cases, it seemed to work properly and I had full telemetry.

It almost acts like a signal is being sent by Mission Planner that shuts down communication or powers down part of the board.  I don't know if this is possible, but as soon as Mission Planner times out, the leds come back on.

I would appreciate any input on this I can get.  I have had good success in the past with this quadcopter and I was just getting to the point where I worked out most of the mechanical bugs.

Thanks in advance

UPDATE:  I tried Mission Planner 1.2.81 on another computer and everything worked normally.  It appears that the only common factor with the problem is MP 1.2.85.  If that is the case, I am going to downgrade to the older version.  Luckily I saved the .msi from a previous installation.

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  • I already updated my mission planner to the latest (.86) however, GoogleSatelliteMap Isn't loading. I have internet connection. What should I need to do?

  • I upgrade my MP today, but same problem. :)

  • This is now fixed in 1.2.86!

    I have had 100% successful connects since upgrading to 1.2.86 today.

  • I finally had a peek at the MP changelog:

    * Mission Planner 1.2.85update map library - this will invalidate your map prefetchremove arial narrow and Century Gothic font issues
    add ability to load a kml linestring as a mission
    add kmz overlay and import support
    fix AC imax limits
    add view flightplan as kml
    fix speech over speak
    fix bad first packet in mavlink logs
    support now DF log gps line
    modify getParam timeout from 0.2 to 0.7

    The items in bold look like they may be related to this issue. I first mentioned the symptoms I was having here:

    I am able to connect to .85 only if I 'trick' it by hitting connect immediately after APM starts flashing LEDs (presumably also right after first connecting to USB). Connection consistently fails if I give APM too much time (bootup completed).I have seen some saying they are having no problems with connecting to .85 via telemetry. Not sure if that will help work this bug out, but figured it's worth a mention.

  • MP1.2.85 fails with usb, 1.2.84 works fine. Tlog attached.


    2013-10-28 19-10-54.tlog

  • Upgrading to this version results in "no RC receiver" error.

    The APM is functioning and RC is working, yet this error is flagged

    The same error appears when playing a log file

  • I taken every software update for MP for nearly a year... this is the first time its been a serious problem.  1.85 is essentially unusable.  It will not connect to any of my APM's


    Looking forward to a fix soon.  In the meantime uninstalling and going back to 1.84



  • Same here.

    Authentic APM 2.6 working fine before with version 1.2.84 on Windows 7 32 bit.

    Upgraded to Mission Planner 1.2.85, no longer connecting.

    Downgraded back to 1.2.84, all fine now.

  • I removed MP 1.2.85 and installed 1.2.84. Connect to APM 2.5 is now working reliably again.

  • I just got my APM 2.5.2 clone yesterday and I installed MP 1.2.85 on two different machines but could not update the firmware and 9 out of 10 times it would time out when connecting.  After seeing this thread, I completely uninstalled 1.2.85 and installed 1.2.75. It works perfectly now.

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