I have read in many places on the site that the Arducopter battery must be switched off or disconnected before connecting to the USB, or irreversible damage may occur. Is this still going to be true on the production release and with your own power distribution board? My feeling is that however disciplined one is, sooner or later it's gonna happen that both get connected together.
If so, couldn't this feature be designed out?
Sorry for the newbie to barge in an old thread like this, but it seems like I actually managed to blow something by hooking up both at the same time.
I wasn't aware that it was potentially a big problem and having just installed the resistors for the voltage measuring I was curious if I could read those from the missionplanner software.
So now, all I get when I plug in the USB is a few leds flash up, then everything dies again and the little blue led on the corner of the IMU dimly flashes 3 times and then all is dead. The computer also says the USB device doesn't work properly.
Does the 3 flashes give any more information about what exactly is blown? Some hardware-guys at work might be able to replace faulty parts on the board, but I'd need to know what to replace of course. This is my first attempt at UAV/multicopter stuff and I'd hate to have to buy an entire new IMU board after just two days :)
Jeroen, it is really difficult to say but it might be that you've blew your main cpu. Do you have FTDI cable? As you could connect that directly to CPU board and test CPUs without IMU board.
Blue led in corner is main power led and it has no any real intelligent behind it.
I now actually suspect the board got the full 11.1V load from my battery-pack.
If the CPU is indeed fried, then anything could be blown I guess. I don't have an FTDI cable, but maybe there's some relative easy way to trace what parts would need replacement? I know people that can replace the chips, but if it's going to take days to figure out which are blown it might be easier to cry in a corner for a bit and order a new set of electronics I'm afraid
Update: I went through the schematics tonight and I'm not still not entirely sure what happened. Something got blown when I (partially) hooked up the battery, but from what I could tell it shouldn't have, since the resistors would've brought down the 11.1V to a more than acceptable level for the CPU to handle.
Anyway, it seems indeed that the CPU still got fried somehow. Detaching the IMU and hooking that up to a USB cable still seems to give some life, so I'm actually hoping that it's just the CPU that's blown and that it didn't take too much stuff with it. Ordered a new APM board and we'll try again when that comes in.