Did I blow my outputs?



I got to the point in my first quad arducopter build where  it came time to load the code, exciting!

With everything connected, (including ESCs) I proceeded to power up the board via USB.

The dim LED struck me as kind of odd, but at this point I don't know that what i've just done is a no. So I make 1 attempt to load the code whith no success obviously. That's when I unplugged it.

Upon closer inspection the manual I found it rather casually mentioned here:



"3. Upload the ArduCopter firmware to the APM.

  • Plug the board into the USB. If you have ESCs connected to the board, you must also be powering the board via a battery (though the power distribution board if you're using the standard ArduCopter frame). If you do have the ESCs connected to the APM board and you don't power the independently of the USB cable, the code will not load and you may blow your outputs. (You can tell you're overloading your board if your APM LEDs are dim). "

I connected the battery, made a minor correction to my sketch folder name/location and the code loaded fine. 


now when I power on the quad the motors beep really fast and nudge just a little....

I calibrated the esc's according to the manual and tested each motor idividually for proper spin direction






Post script,


in kinderkram's build log, at the bottom (after you fry your outputs)

there is this warning

When you plug in the USB make sure you don't have your ESCs and motors connected.
Otherwise you will blow your outputs!

you guys know the next question.


Why is this warning not in the ArduCopter manual?

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  • Hi! When this is done, would that also affect the inputs of the RC?


    When the APM does not have an output, what steps do we need to do to revive it?

  • Hmm, I did not read the 3 pages, so excuse me and ignore if I am saying something wrong.

    I had the same problem several times, disconnecting the battery and forgetting the USB, though I never fried anything because my PC cuts off the power on the USB and I receive a message saying something like : "the USB port is drawing too much power that it can handle. USB port has been cut off, please disconnect blablabla..." maybe because it is a Mac or something, but I guess most PCs have some kind of overdraw protection...

    So logically this issue should not be a problem, but there is surely a way to upgrad the APM.

    Anyway just my 2 cent

  • I also have this same problem. I did it like it says in the Wiki and was ok. I then wrote to Jani and he told me NOT to connect both USB and Lipo or I would blow my outputs. I did this and guess what, that's right, dim light and constant beeps and resets. I asked Jani to replace my board and NOTHING! No response!!

    Here is what he wrote:
    "As a safety reason, do not keep your battery connected while connecting your USB.

    There have been some incidents that people has burn their outputs which still is mystery why. So we gave instruction that not to have battery + usb powers at same time. I personally have been having them many times and no problems but follow wiki pages for safety.

    What I am trying to figure out is he is telling me NOT to connect both, but follow the Wiki?? The Wiki states to use both?? Great information from one of the leaders! Now I am out $170ish !! You might want to fix the Wiki to represent the PROPER procedures!! You might want to have the Wiki reflect that you should not connect ALL ESC wires to APM! There is NOTHING stating this! How the hell are people supposed to know this stuff?? We look to "the leaders" for support but get the wrong information?? WTF is that all about??
  • Moderator
    Can't this all be avoided by just not powering the ESCs via APM? I mean, just remove the power pins from the ESC plugs and only use the signal wires? I am only running signal wires to ESCs and power my board/receiver via USB all the time. The ESCs are only powered when the flight pack is plugged in.
  • hello
    i have some problem power up ESC beep really fast and motor nudge, but hookup USB cable use configurator click send motor command and it work fine disconnect usb cable still ok, but once removed battery, powerup same thing happen again.
    is circuit board blow?

  • Awesome that clears things up! I been unplugging everything but the rx cables and it was getting to be a bit tedious.

  • Chris when you say a battery do you mean our main battery that is powering our motors and ESC and IMU through BEC? And if you do mean our main battery is it ok to have all the motors plugged into the board when we connect to the config tool.

  • so, how can we tell if the MUX is fried ?
    In case of nay non function to know that is not the problem?
    I understand that all functionality is OK , all blinking leds etc. no problem connecting to pc , but the out signal is not working , in case of MUX prob ?

    I`m still waiting for my motors and esc, but I connected 2 servos to OUT 4 and 5 with this code.
    APM_RC.OutputCh(4, APM_RC.InputCh(6)+(pitch)*1000); // Tilt correction
    APM_RC.OutputCh(5, 1500+(roll)*-400); // Roll correction
    The servos are receiving electricity when system started , but not responding to the giro etc.
  • I am by no means an expert, but wouldn't wireless programming via XBee be a great solution to get rid of this problem? This would also be extremely helpful for those of us who are developing and playing with the code as it would allow for us to do wireless uploads of code changes while debuging, especially during test flights.

    I am not sure how this setup would work with our current ArduCopter config as I don't have my Arducopter fully built yet, but HERE IS A LINK to a XBee wireless programming tutorial that seems like it might be something to look into as a solution to this problem and maybe even add to the WIKI as a required step. (We can add COMPLETELY WIRELESS PROGRAMMING to the ArduCopter feature list!)

    I know I would love NOT to have to unlplug my ESC's etc and plug my board in via USB during test flights just because I am an idiot and mis-typed one of my variables, or forgot to uncomment parts of my code!!
    Forgive me if this is already posted somewhere in the forum, i haven't quite made it through all of the posts yet
    Xbee Adapter - wireless Arduino programming
  • If you email Chris Anderson, he will put your name on the list of people to help write the manual. That's the best way to get this into the manual.

    I see it has been added, perhaps there should be a warnings section, listing all the potential-to-fry or potential-to-crash warnings.
This reply was deleted.


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