1 Computer Fundamental ITD1382 Coursework : 100% 1. Tests 2. Quizzes (Short) 3. Assignments Module Value : 3.0

2 Course Content Numbering System (Binary, Hexadecimal …) Logic Systems and Digital Circuits Computer Systems Architecture Hardware Components System Resources The Boot Process Assembling a Computer Hardware and OS Maintenance Operating System Fundamentals Windows Operating Systems (Windows 2003 Server / XP Professional) Linux Operating Systems (Red Hat / Fedora Core)

3 Teaching Materials Lecture Notes Tutorial Exercises / Solutions Tests & Quizzes / Solutions Lab Sheets Textbook - Cisco Networking Academy Program IT Essential I: PC Hardware and Software Companion Guide, Cisco Press Reference book – Cisco Networking Academy Program IT Essential II: Network Operating System Companion Guide, Cisco Press Note: Download from webct ( )

4 Lecture 1 Numbering System

5 Numbering Systems in Computer Binary (Base 2) e.g Octal (Base 8) e.g (Digit with value 0 -7) Hexadecimal (or Hex - Base 16) ABCDEF 16 (Digit with value 0 – F) How to convert between different base?

6 Conversion from decimal to binary Example: Convert 345 (in decimal) to binary 345 MOD 2= 1(345/2 = 172) 172 MOD 2= 0(172/2 = 86) 86 MOD 2= 0(86/2 = 43 ) 43 MOD 2= 1(43/2 = 21 ) 21 MOD 2= 1(21/2 = 10 ) 10 MOD 2= 0(10/2 = 5 ) 5 MOD 2= 1(5/2 = 2 ) 2 MOD 2= 0(2/2 = 1 ) 1 MOD 2= 1(1/2 = 0 ) Ans:

7 Conversion from Binary, Octal, Hexadecimal to Decimal - Power Series Example convert to decimal Decimal representation of = 1x x x x x x x x2 1 +1X2 0 = Example Convert (oct) to decimal Decimal representation of =5x x x8 0 =

8 Conversion from Binary to Octal Conversion from binary to oct => 531 (oct) By using MOD 8 and (MOD – find the remainder) Binary to Octal

9 Conversion from Binary to Hexadecimal Conversion from binary to hex => 159 (hex) By using MOD 16 (MOD – find the remainder) Binary to Hexidecimal A 1011B 1100C 1101D 1110E 1111F

10 Conversion from decimal to octal or hexadecimal Example Convert to octal representation 345 MOD 8= 1(345/8 = 43) 43MOD 8= 3(43/8 = 5 ) 5MOD 8= 5 Ans: Example Convert to hexadecimal representation 345MOD 16= 9(345/16 = 21) 21MOD 16= 5(21/16 = 1 ) 1MOD 16= 1 Ans:

Conversion from decimal to binary Example Convert to binary representation x 2= x 2= x 2= x 2= Ans: Convert to decimal rep.: Stop or: 1x x x x2 -4

12 Conversion from decimal to octal Example Convert to octal representation x 8= x 8= Ans: Stop

13 Arithmetic Operation (Binary) Addition BinaryDecimal Carries00011 Augend Addend Sum Augend+ Addend= Sum 19+11= = 11110

14 Arithmetic Operation (Binary) Subtraction e.g. BinaryDecimal Borrows11000 Minuend Subtrahend Difference If Subtrahend > Minuend? => NEGATIVE NUMBER

15 Arithmetic Operation (Binary) e.g. BinaryDecimal Borrows Minuend Subtrahend Difference?110100?? Negative number ? How negative number is represented in binary format?

16 Signed Number How to represent negative number (binary number) Use a sign bit i.e. 0 represent positive and 1 represent negative e.g. +10 => and -10 => Problem with two zero i.e or So, it may not be a good solution for representing binary number.