INPUT/OUTPUT DEVICES AND PROCESSORS

INPUT/OUTPUT DEVICES OR I/O DEVICES:

Input/output devices enables communication between user and the software.
INPUT DEVICE:
Any peripheral device that provides input to the computer is called as Input device.Input devices are used to provide information to the computer.

Some of the input devices are,

• Microphone  
• Keyboard
• scanner 
• Web camera

OUTPUT DEVICE:
Any peripheral device that receives output from the computer is called as output device.Output devices are used to display or receive data's from the computer.

Some of the output devices are,

• Monitors (LCD,LED,CRT etc..)
• Projector
• Speaker
• Printer 

INPUT/OUTPUT PROCESSORS OR I/O PROCESSORS:

The I/O processor is a type of processor that is separate from the main processor of a computer.This i/o processor is designed only to handle input and output processes of the computer.
INPUT/OUTPUT INSTRUCTIONS:

An i/o instructions makes the transfer of data between peripheral device's and main memory.And this input/output instructions enables Central Processing Unit CPU to control the peripheral devices that has connected to it.
INSTRUCTION FORMAT:

OPCODE ADDRESS DATA

Some of the I/O instructions are,

1. START IO 
2. HALT IO 
3. TEST IO

The I/O instructions executed by the Input Output processors are called as Channel Comment Words CCWS.
TYPES OF CCWS:

1. Data Transfer instructions
2. Branch Instructions
3. IO device and control Instructions