Now most modern computers are equipped with USB ports instead of COM interfaces. In order to set up serial communication, a user needed to specify a correct port number and the speed of data transmission. This is due to the fact that initially almost any equipment, including GPS receivers, was external, and its connection to the computer was established via a serial cable attached to one of the PC’s hardware ports. However, modern standards of compatibility between serial equipment and its controlling software have been formed for quite some time around the concept of COM ports which are now seen as archaic. A COM port has been replaced by USB - a more modern method which does not require special knowledge for implementation. Today serial port communications are not that common as they once were. However, a serial mouse as well as other peripheral devices can also interact with a computer via a serial interface. If the parallel port was mainly used to connect printers, the COM port (by the way, COM is short for communication) usually worked with telecommunication devices such as modems.

However, its scope of application was somewhat different from that of the parallel port. On first machines, the COM port was used for connecting peripheral devices. The serial port appeared long before personal computers of the IBM architecture were introduced. What are the advantages of serial data transmission?Ī COM port is a bidirectional serial interface that allows sending and receiving data bit by bit.Although in modern computers the COM port is of limited use, information about it may be useful to many users. Along with the parallel port, the COM port, or serial port, is one of the traditional computer I/O interfaces which can still be found on POS systems, some medical equipment, lab instruments, and other old-timey hardware.

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