Processing Device || CPU || Central Processing Unit
Processing Devices:
The
Central Processing Unit (CPU) is the main processing device of the computer. It
is also called microprocessor. The microprocessor (CPU) can be considered as
the brain of the computer. The microprocessor performs all the arithmetic and
logical operations in the computer. It processes the data according to the
given instructions and gives result.
The
speed of the computer also depends on the microprocessor. The modern CPUs are
small in shape and contain multiple metallic connectors called pins on the underside.
The
devices which are used to process the input data according to the given set of
instructions are called processing devices.
Parts
of Microprocessor/ CPU
Basically
the microprocessor (CPU) has main three parts. They are:
i)
Control Unit (CU)
ii)
Arithmetic Logic Unit (ALU)
iii)
Registers
Control
Unit (CU)
The
control unit controls and coordinates all the activities of the computer
system. It directs all the parts of computer system to perform their tasks. The
control unit controls the execution of instructions given to the computer. It
controls the movement of data and instructions from the input device and stores
them in the main memory. It communicates between LU, registers and memory. It
also communicates between the CPU and all input, output and storage devices.
So, it is known as the manager of the CPU.
Arithmetic
Logic Unit (ALU)
The
Arithmetic Logic Unit (ALU) performs all the arithmetic and logical operation
in the computer. In arithmetic operations, ALU performs the addition,
subtractions, multiplication and division of numeric data. In logical operations,
ALU compares the numerical data as well as alphabetic data. For example, it
checks whether the number is greater than the second, less than the second or
equal to the second.
Registers:
The
CPU also consists of a number of registers in it. It is a temporary storage
device which holds data and instructions as long as it is being interpreted and
executed. The register can contain the address of memory location of data
rather than the actual data itself. When the data and instructions are fetched
from memory for processing then these data have to be stored in one of the
registered of the CPU.