Basic operations of computer my assignment

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ASSIGNMENT
BASIC OPERATIONS OF COMPUTER
____________
Credit Assignment
By
NAZISH JAMALI
Credit Assignment for BS Education (Computer skills)
Date of the submission
15-Febuary-2016

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What are the five basic operations performed by the
Computer?
All computer systems perform the following five basic operations, for converting raw
input data into information, which is useful to their users
Input: the general meaning of input is to provide or give something to the computer
We categorize computer devices as input devices because we use these devices to send
instructions to the computer, some common examples of computer input devices are:
 Mouse
 Keyboard
 Microphone
 Scanner
 Light pen

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Output: An output device is any device used to send data from a computer to another
device or user. some common examples of computer output devices are
o Monitors
o Projectors
o Speakers
o Headphones
o Printers
Memory Unit: The function of memory unit is to store programs and data. There are 2
classes of storage
Primary Storage: Primary storage of a computer, also known as its main memory, is
used to
hold pieces of program instructions and data, intermediate results of processing, Primary
storage can hold information only while computer system is on. As soon as the computer
system switches off or resets, the information held in primary storage is erased.
Secondary Storage: Secondary storage of a computer, also known as its auxiliary
storage, is used to take care of the limitations of primary storage. Secondary storage is
much cheaper than primary storage and it can retain information even when a computer
system switches off or resets. Magnetic disk is the most commonly used secondary
storage medium.

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Control Unit
A control unit or CU is circuitry that directs operations within a computer's processor. It lets the
computer's logic unit, memory, as well as both input and output devices know how to respond to
instructions received from a program. Examples of devices that utilize control units
include CPUs and GPUs. A control unit works by receiving input information that it converts into
control signals, which are then sent to the central processor. The computer's processor then
tells the attached hardware what operations to carry out. The functions that a control unit
performs are dependent on the type of CPU, due to the variance of architecture between
different manufacturers. The following diagram illustrates how instructions from a program are
processed.
(Figure 1)

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Arithmetic Logic Unit (ALU)
The ALU is a complex digital circuit; one of many components within a computer's central
processing unit. It performs both bitwise and mathematical operations on binary numbers and is
the last component to perform calculations in the processor. The ALU uses to oprands and code
that tells it which operations to perform for input data. After the information has been processed
by the ALU, it is sent to the computer's memory.
Multiple Arithmetic Logic Units can be found in CPUs, GPUs (Graphics Processing
Unit) and FPUs (Floating Point Unit). In some computer processors, the ALU is divided into an
AU and LU. The AU performs the arithmetic operations, and the LU performs the logical
operations.
Binary 0s-1s Bits
GPU
Operands

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Central Processing Unit (CPU)
CPU stands for Central processing unit. It is also known as microprocessor or
processor. A CPU is brain and heart of a computer. Which receives data input,
processes information, and executes instructions. The CPU is the most important
element of a computer system. The CPU is consisted of thin layers of thousands
of transistors. Each transistor receives a set of inputs and produces output. Here
are four important functions of CPU, Fetch, Decode, Execute, and Write back
The CPU was first developed at Intel with the help of Ted Hoff and others in the
early 1970's. The first processor released by Intel was the 4004 processor,
shown in the picture.
Components of the CPU
In the CPU, the primary components are the ALU (Arithmetic Logic Unit) that
performs mathematical, logical, and decision operations and the CU (Control Unit)
that directs all of the processors operations, (As Shown in Figure 1).
Over the history of computer processors, the speed (clock speed) and capabilities of
the processor have dramatically improved. For example, the first microprocessor
was the Intel 4004 that was released November 15, 1971, and had
Marcian Ted Hoff

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2,300 transistors and performed 60,000 operations per second. The Intel Pentium
processor pictured below has 3,300,000 transistors and performs around
188,000,000 instructions per second
____________________________________________________________
 Choose the correct answer.
(a): The task of performing arithmetic and logical
Operations is called:
(i) ALU (ii) editing (iii) storage (iv) Output
(b): The ALU and CU jointly are known as
(i) RAM (ii) ROM (iii) CPU (iv) None of above
(c): The process of producing results from the data for
Getting useful information is called:
(i) Output (ii) input (iii) processing (iv) storage