Computer System Architecture: Understanding Hardware, Software, and Networking

COMPUTER SYSTEM ARCHITECTURE
Introduction: In this era of technology computer has an important role in a human being. In every field
related to human services such as education, medical, defiance, etc. nothing can be done without a
computer. A computer is an electronic machine that interacts with the user, take his input and provide
result according to his operation and also provide facilities for storing the data. Another advantage of the
computer is that it provides the networking facility to the users in which users can share the data among
them from different locations.
In this chapter, I have discussed computer architecture and how it works. I included following things
about the computer, Von Neumann architecture of the computer and its part such as I/O, memory unit,
control unit, and arithmetic and logical unit. I discussed the operating system and its key features or its
services. And I designed a prototype network for the ACME as a consultant for ACME (O’Reilly, 2018).

LO1 Explain the relationships between hardware components and the subsystems used in a computer
system
P1 Identify the main subsystems of a computer and explain how they are organised and connected.
Here I have given a diagram of Von Neumann architecture; following are the key features of-of this
architecture.
Figure 1: von Neumann architecture
Source (Tipsandarticles, 2018.)
Memory: commuter has a memory unit which is used to hold and store the data, this also called as RAM
that means random access memory.
Types of memory in the computer: basically it is categorized in type’s primary memory and secondary
memory.
Primary memory: It is also called volatile memory because it is not able to store the data permanently,
that is known as RAM

Random access memory (RAM): It has an ability of both read and writes but when at the condition of a
power failure your data has been lost permanently. This may be following type DRAM, DRDRAM and
SRAM.
Secondary memory: this memory is a permanent memory and also known as an external memory of a
computer such as floppy disk and magnetic disk.
Read Only Memory (ROM): it is the permanent mammary of the computer that is available in a huge
range in modern days but it can be read-only. And there is no loss of data at the time of power failure.
There are several types of the room such as PROM, EPROM, and EEPROM.
Cache Memory: it is the fastest memory and stores a little data as compared to the main memory of
commuter.
BIOS: it means basic input and output system; it is in the form of software that stored on a memory chip
of the motherboard (Informationq, 2016).

Control unit: this unit is the mind of the computer that manages and controls the flow of data to outside
the memory and inside the memory and also deals with programming instructions. And this contains the
registers to store the intermediate value.
Input and output:
Input: Users that enter the data for processing that is known as input and this input can be feed by
various input devices which are given below.
List of input devices: mouse, keyboard, joystick, barcode reader, and scanner.
Output: after entering the input users expect to the result after manipulating the data devices that shows
the result is known as output devices,
List of output devices: monitor, printer, speaker, plotter and projector
Arithmetic logic unit(ALU): All the arithmetic and logical calculations are performed in this part of a
computer such as addition subtraction multiplication and divide or logical calculations “greater than, less
than and equal to” all these are performing by ALU (Teach-ict, 2018)
Hardware: generally computer contains the various mechanical electrical and electronic components
these all devices are known as hardware devices such as a motherboard, mouse, flash drive floppy disk
etc.
Software: it can not touch by a human being it is a set program or instructions in a various programming
language such as Java, python and c++. These software’s such as system software, application software
etc.
The relationship between software and hardware:
Software trigger to the hardware to perform any specific work in another word it can be said that software
and hardware are the soul and heart of the computer, for example, there is software of AutoCAD that
trigger the hardware to make a design (Das, 2018).

P2 Explain the purpose of the Central Processing Unit(CPU) and include details on its operation.
Purpose of the Central Processing Unit(CPU):
The main objective of the CPU is to be work on programming instructions. It is designed to execute the
particular instructions and the set of instructions carried out by the CPU to meet the purpose.
Figure 2 control processing unit
Source (Cssforum, 2018)

The function of CPU:
1. Fetching step:
 This means retrieving the instructions from the memory and stores it at the instruction register.
 And instruction address is to be stored at another register known as program counter register (PC)
2. Decoding step: it contains the identification of programming code that tells to the processor that which
operation is to be performed.
3. Executing step: this means performing of operations according to instruction code for an example, an
instruction that has an arithmetic operation with integer number then ALU connect to the relevant
memory address hence;
 Data is to be passed through data bus from memory to ALU.
 Then ALU execute the necessary operation
 After result passes through data bus from the ALU
Components of CPU: there are various components in a central processing unit which are following:
Arithmetic and Logic Unit (ALU): There is an ALU in the central processing unit that contains
electronic circuitry for performing the logical and arithmetic operations with the integers.
Integer arithmetic operations are (multiplication and additions) and logical operations are OR, NOT,
AND etc. and also there is a floating point unit that used to perform the operation on floating point
numbers. And also there is a resister which is used to store the data temporary that is known as an
accumulator (Cssforum, 2018)