introduction to microprocessor

Introduction to Microprocessor

Definition:  “The microprocessor is a multipurpose, clock driven, register based, digital-integrated

circuit which accepts binary data as input, processes it according to instructions stored in

its memory, and provides results as output.”  “Microprocessor is a computer Central Processing Unit (CPU) on a single chip that

contains millions of transistors connected by wires.”

:  A microprocessor is designed to perform arithmetic and logic operations that make use

of small number-holding areas called registers.  Typical microprocessor operations include adding, subtracting, comparing two numbers,

and fetching numbers from one area to another.

2. Components of Microprocessor

 Microprocessor is capable of performing various computing functions and making

decisions to change the sequence of program execution.  The microprocessor can be divided into three segments as shown in the figure,

Arithmetic/logic unit (ALU), register array, and control unit.  These three segment is responsible for all processing done in a computer.

Arithmetic and logic unit (ALU)  It is the unit of microprocessor where various computing functions are performed on

the data.  It performs arithmetic operations such as addition, subtraction, and logical operations

such as OR,AND, and Exclusive-OR.  It is also known as the brain of the computer system.

Register array

 It is the part of the register in microprocessor which consists of various registers

identified by letters such as B, C, D, E, H, and L.  Registers are the small additional memory location which are used to store and transfer

data and programs that are currently being executed.

Control unit  The control unit provides the necessary timing and control signals to all the operations

in the microcomputer.  It controls and executes the flow of data between the microprocessor, memory and

peripherals.  The control bus is bidirectional and assists the CPU in synchronizing control signals to

internal devices and external components.  This signal permits the CPU to receive or transmit data from main memory.