I/O Ports
=> I/O port is a channel that enables I/O devices to communicate with the system.Different type of ports like serial port, parallel port,USB port are available.
serial port is used to transfer a single bit of data at time.it can be used to connect any type of serial device like a mouse , moderm ,printer etc.
UNIVERSAL SERIAL BUS (USB) is an I/O port used to connect different external device like a hard disk drives,printers,mice,scanners etc.
A PARALLEL PORT can transfer multiple bits,but a SERIAL PORT can transfer only one bit at a time.
Serial port
I/O port is a logical channel the I/O devices to communicate with the system.
there are different kind of port like serial port,parallel port, USB port etc.
serial port is used to transfer single bit of data at a time.the serial ports confirm to RS -232c or RS-422 standards.it can be used to connect any type of serial device like a mouse , moderm ,printer etc. USB is also a type of serial port and stands for
Universal Serial Bus. USB is a much more complicated standard than the typical 9-pin D-sub serial port you might find on a desktop computer (RS-232 standard). Anyway you look at it, most data transmission between different devices is sent serially . the different kinds of serial port are 9 pin D type male connector and 25 pin D type male connector from the system side.they are called COM port (COM -communication port).
Serial data communication in a PC
The data is sent as bit by bit in a serial communication.The data is divided into bits and are transmitted sequentially.the data is sent between devices through the communication channel.the communication channel is a physical wire which connects the communicating devices.in serial communication one channel can transfer only one bit at a time.serial communication is cheaper as it needs only one wire.it is suitable for long distance communication since it has less distortion due to noise and interference.the lenght of the wire required for transmitting is less.the speed of transmission is less.
example - modem
