The chip has been crushed.
Today the download line of the GND download line from the chip seat off, may be too tight, the line is broken. And then re-do, the result is too hard, the chip block pin broken. Now listen to a digital group of users of the proposal welding a copper wire up, it seems that can be used, but the seat to the hot bad look. Because it is not fixed well, repeated reasons. Bought on the Internet two, this thing or buy the package only gave two, did not consider the user is not professional may appear problems. Give a backup just fine, although not expensive, but freight hurt.
Short circuit
Do a silly thing, test their own chip block is the path, make an LED inserted in the bread board, test.
This is probably the case, the moment saw the thread, because the brain and circuit are short-circuited.
Love single-chip computer · Problems that arise in the experiment