config_done pin is drived down again after download

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Is the working time constant or random, I mean between configuration done and configuration lost?

Does your design contain some particular features, like remote update or any security check device?

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I try it again this afternoon, it seems that device could work normally now. I don't change any in my design. Under this situation, I don't know whether it is stable to use. I think the working time is random. And it can only last few seconds this before.

Besides this, I don't use remote update or security check device in my design.