Computer
- CPU(Central Processing Unit)
Central Processing Unit (CPU) consists of the following features
−
- CPU is
considered as the brain of the computer.
- CPU performs
all types of data processing operations.
- It stores
data, intermediate results, and instructions (program).
- It controls
the operation of all parts of the computer.
CPU itself has following three components.
- Memory or
Storage Unit
- Control Unit
- ALU(Arithmetic
Logic Unit)
Memory or Storage Unit
This unit can store instructions, data, and intermediate
results. This unit supplies information to other units of the computer when
needed. It is also known as internal storage unit or the main memory or the
primary storage or Random Access Memory (RAM).
Its size affects speed, power, and capability. Primary memory
and secondary memory are two types of memories in the computer. Functions of
the memory unit are −
· It
stores all the data and the instructions required for processing.
· It
stores intermediate results of processing.
· It
stores the final results of processing before these results are released to an
output device.
· All
inputs and outputs are transmitted through the main memory.
Control Unit
This unit controls the operations of all parts of the computer
but does not carry out any actual data processing operations.
Functions of this unit are −
· It is
responsible for controlling the transfer of data and instructions among other
units of a computer.
· It
manages and coordinates all the units of the computer.
· It
obtains the instructions from the memory, interprets them, and directs the
operation of the computer.
· It
communicates with Input/Output devices for transfer of data or results from
storage.
· It
does not process or store data.
ALU (Arithmetic Logic Unit)
This unit consists of two subsections namely,
- Arithmetic
Section
- Logic Section
Arithmetic Section
Function of arithmetic section is to perform arithmetic
operations like addition, subtraction, multiplication, and division. All
complex operations are done by making repetitive use of the above operations.
Logic Section
Function of logic section is to perform logic operations such as
comparing, selecting, matching, and merging of data.
