standard computer mother boards contain 6 ports, 4 serial ports and 2 parallel ports. Serial ports can send or receive data on its wires at one direction at a time while Parallel Ports can send and receive data in both direction in its wires simoultaenisly.

Below is the list of ports mapped to its hexadecimal values:

COM1 3F8H
COM2 2F8H
COM3 3E8H
COM4 2E8H
LPT1 378h
LPT2 278h