I just received a call from someone who said he was a courier from JD.com. Thinking about the award I won in the forum, I felt that the prize must have arrived. The picture above is, a very small Blue...
On my AT89S52 learning version instruction sheet, the buzzer and the fourth light of the diode are all controlled by the P1.3 pin. When programming with KEIL, the light is on and the buzzer is also on...