Computer Fundamentals Lecture Notes PDF

Computer Fundamentals Dr Mohammed Kayed 02 Number Systems Introducing 4 numbering systems, and discussing the conversions among these systems. Also, briefly showing signed & unsigned numbers’ representations. ...

Computer Fundamentals Dr Mohammed Kayed 02 Number Systems Introducing 4 numbering systems, and discussing the conversions among these systems. Also, briefly showing signed & unsigned numbers’ representations.  Table of contents 01 02 03 Introduction Number Systems Hardware A breif introduction to Numbering systems and Details about computer computers and their use conversions from one HARDWARE in our Society system to another  Table of contents 04 05 06 Software Networks Security Details about computer An introduction to An introduction to SOFTWARE computer Networks and computer Security the Internet Data, Program and Information  Introducing Number Systems Four different types of the number system: 1. Binary number system (base 2) 2. Octal number system (base 8) 3. Decimal number system(base 10) 4. Hexadecimal number system (base 16). Introducing Number Systems Decimal Number System Decimal Number System Decimal Number System Decimal Number System Binary Number System Binary Number System Binary Number System Binary Number System Binary Number System  Binary Number System Many ONLINE number system converters are there on the Web. Hexadecimal Number System Hexadecimal Number System Hexadecimal Number System Hexadecimal Number System Hexadecimal Number System  Octal Number System An octal number is represented using base 8. Octal representation is just a simple extension of binary and decimal representations but using only the digits 0 to7. Octal Number System Signed & Unsigned Integers  Signed & Unsigned Integers Representation of integer, character and floating point numbers in binary Machine instructions operate on data. The most important general categories of data are: 1. Addresses – unsigned integer 2. Numbers – integer or fixed point, floating point numbers and decimal 3. Characters – IRA (International Reference Alphabet), EBCDIC (Extended Binary Coded Decimal Interchange Code), ASCII (American Standard Code for Information Interchange), or Unicode 4. Logical Data  Unsigned Integers Can contain only magnitude of the number. We always assume that there is a positive sign symbol in front of every number. N bit binary number represent its magnitude only. Zero (0) is also unsigned number. Every number has only one unique binary equivalent form, so this is unambiguous representation technique. The range of unsigned binary number is from 0 to (2n-1).  Unsigned Integers Example-1: Represent 92 in unsigned binary number. = (92)10 = (1x26+0x25+1x24+1x23+1x22+0x21+0x20)10 = (1011100)2 It’s 7 bit binary magnitude of the decimal number 92.  Unsigned Integers Example-2: Find range of 5 bit unsigned binary numbers. Also, find minimum and maximum value in this range. Since, range of unsigned binary number is from 0 to (2n-1). Therefore, range of 5 bit unsigned binary number is from 0 to (25-1) which is equal from minimum value 0 (i.e., 00000) to maximum value 31 (i.e., 11111).  Signed Integers Historically: 3 approaches could be used. Sign-and-magnitude Ones-complement Twos-complement For all 3, the most-significant bit (MSB) is the sign digit 0 ≡ positive 1 ≡ negative Twos-complement is the important one (Simplifies arithmetic - Used almost universally) Signed Integers Signed Integers  Signed Integers Get the representation of ones complement (6 bit) for the following numbers: i) +710 ii) –1010 Solution: Solution: (+7) = 0001112 (+10)10 = 0010102 So, (-10)10 = 1101012 Signed Integers Signed Integers Signed Integers Signed Integers  Coding Systems for Text-Based Data ASCII (American Standard Code for Information Interchange) – Coding system traditionally used with personal computers. EBCDIC (Extended Binary- Coded Decimal Interchange Code) – Developed by IBM, primarily for mainframes.  Coding Systems for Text-Based Data Unicode – (32 bits per character is common) – Universal coding standard – Replacing ASCII as the primary text-coding system. Coding Systems for Other Types of Data Coding Systems for Other Types of Data – Audio – Video – Machine Language Coding Systems for Other Types of Data