Microprocessor:

A multipurpose, programmable logic device that reads instruction from a memory, accepts binary data as input and process data according to those instructions and provides a result as output is called microprocessor. Nowadays microprocessor is also called processor. It is a complete CPU built on a single chip by using VLSI or ULSI technology.                    

Intel Corporation of USA developed the first microprocessor named „Intel 4004‟ in 1971 AD. It contained about 1600 transistors. It was a 4-bit microprocessor and process only 4-bits of data at a time. The modern processors are available in 32-bit, 64-bit or higher bits world length.

The important characteristics of a microprocessor are the width of address bus, data bus, clock speed and its instruction set architecture. Processors are also often classified as being either RISC (Reduced Instruction Set Computer) or CISC (Complex Instruction Set Computer).

The microprocessor is responsible for the following functions:

a)     To control and co-ordinate all the operations and other components of the computer system.

b)     To carry out processing.

c)     To give commands to all the other components of the computer system.

d)     To control the sequence of operations in the computer system.

e)     To interpret the data, instruction and information in the computer system.

The microprocessor has three components.

• Control unit(CU)
•  Arithmetic and Logic Unit (ALU)
• Register