2.？ In the device manager, the following figure will appear-> Click on the port to view; ?

(Provided that the device needs to be connected, there will be no connection).

Serial interface is called serial port for short, also called serial communication interface or serial communication interface (usually referred to as COM interface), which is an extended interface adopting serial communication mode.

Serial interface? (serial interface) refers to the sequential transmission of data bit by bit, which is characterized by simple communication lines. As long as a pair of transmission lines (telephone lines can be directly used as transmission lines) can realize two-way communication, thus greatly reducing the cost, especially suitable for long-distance communication, but the transmission speed is slow. The communication mode in which each bit of information is transmitted bit by bit in sequence is called serial communication. The characteristics of serial communication are: the transmission of data bits is carried out in bit order, and at least one transmission line is needed; Low cost but slow transmission speed.