3HC ramdom restart

[PetrKroupa]

I have problem with ramdom restarts 3HC board. After M122 B1 i see last reset cause reset button. Im sure that this is not possible. Firm 3.4.1.

Ideas?

[dc42]

@petrkroupa please check whether R30 looks correctly soldered. It pulls the reset input of the MCU up to +3.3V. It is located close to the corner of the address switch block, near the IO_0 connector.

[PetrKroupa]

@dc42 - Thanks for the super fast reply. I checked the R30 and it looks good. As I looked at the entire board with a magnifying glass, I found a small piece of copper wire. Smaller than the smallest, almost like hair. It is located near the R30. It is quite possible that he was touching, but as I took out the board to check it, I have no idea if he was already there or fell from somewhere. In truth, I have no idea where he came from. I cleaned the entire 3HC with compressed air and will try another test print tomorrow. I'll let you know if the problem will happen again.

[PetrKroupa]

@dc42 - problem solved. Thanks for help.