Connecting to Crazyflie while charging bricked Crazyflie

[erget]

Hi there,

I seem to have bricked my Crazyflie, although I can't figure out why.

I'd just flown my Crazyflie until the battery was down, as I've done quite a few times since I got it. No major crashes or anything occured. When the red LED was lit continuously, I stopped flying and plugged it in, and the CF started charging. I wanted to take a look at the TOC it sends to the CF Client, so I tried to connect to it with the radio while it was still charging - which I've also done before - and managed to do so.

Before I could do anything more than see that the Client could tell that the CF wasn't 100% level, though, I lost the connection due to packet loss. The CF's LEDs were still on, so I thought that it might be some kind of interference because I was charging. Therefore I disconnected the charger and turned on the CF. It turned on and the propellers turned. I tried to establish another connection, but couldn't due to packet loss again. So I turned off the CF and plugged it back into the charger.

This time, the LEDs didn't turn on and the propellers didn't turn. Since then (it's been about an hour) the CF doesn't react to anything. If I plug it into the charger, nothing happens, and if I try to turn it on without it being connected to the charger, also nothing happens. Have I bricked my CF? What can I do?

Thanks!
Daniel

[TheFrog4u]

The firmware might be currupted somehow? Have you tried to reflash? Instructions

[erget]

Thanks for the tip, but not dice.

I flashed the firmware first thing when I got the Crazyflie, but this time it didn't work. When I try to power on the CF, absolutely nothing happens - no LEDs, no spinning propellors, nothing

[tobias]

Hmm, strange. Do you have access to a multimeter? My initial guess is that something happened with the power management chip.

Start by connecting the USB and measure the voltage between the two through hole pads located just behind the USB connector. Do you get ~5V? Also measure the battery voltage.

If you get voltages at those two places something happened to either the power management chip or the on/off logic. Then contact Seeedstudio customer support.

[erget]

Tobias, it sounds like you're right. When the Crazyflie is connected to USB I get *exactly* 5V. I'm not sure how to measure the battery voltage - I disconnected the battery, but it doesn't like like I oculd use the multimeter on it using the adapter to connect to the CF and I don't want to take it out of its wrapping. But since the CF had worked for electronics tests without the battery or having to turn it on when I connected it to the USB adapter in the beginning, I'd still expect a reaction when I plug it in. I'll contact Seeedstudio. Thanks for the quick help!

[tobias]

You can measure the battery voltage on the backside of the connector. Where it says + and -.

[erget]

You can measure the battery voltage on the backside of the connector. Where it says + and -.

Got it. I get 1.78 at the battery. Interestingly, when I plugged it in again to check it all the LEDs flashed, but not in the normal pattern, and then it died again.

[tobias]

You don't happen to have a spare battery do you, or maybe an external single cell LiPo charger which you could charge the battery in? I think the LiPo protection circuit (PCM) inside the battery is disconnecting it due to under voltage. There is still something wrong with the power management circuit but testing the Crazyflie with a charged LiPo would be a good first trouble shooting step.

[erget]

Sadly, no. But I'll ask around at work, maybe one of the colleagues has one. Thanks for the tip!