1. Lesson Aim (Data representation) To be able to: Convert B/D & D/B Convert D/H & H/D Convert H/B & B/H Perform simple binary arithmetic Represent a number with fractional part in binary

2. Starter (15) Bit, bits, nibble, byte, kilobyte, megabyte, gigabyte, terabyte, petabyte Bit, bits, nibble, byte, kilobyte, megabyte, gigabyte, terabyte, petabyte Explain the capacity for each one Explain the capacity for each one Find out what a (word) is Find out what a (word) is Find out what computers use to store data Find out what computers use to store data Explain why a 500GB hardware is not actually 500GB but 465GB Explain why a 500GB hardware is not actually 500GB but 465GB

3. The bigger picture Why is binary important? Why is binary important? Fundamental to all modern computers Fundamental to all modern computers Used to represent data stored on a computer Used to represent data stored on a computer It influences: encryption, error checking, data compression etc It influences: encryption, error checking, data compression etc Data transmission Data transmission

4. Activity 1 (15) Binary 1/0 1= high voltage 0 = low Binary 1/0 1= high voltage 0 = low Denary/binary B/D Denary/binary B/D Use 8 bit system Use 8 bit system B/D = count the ones B/D = count the ones D/B see if it fits D/B see if it fits Access Google Docs and download the worksheet (Inside 5.1 folder) Access Google Docs and download the worksheet (Inside 5.1 folder)

5. Activity 2 (15) Hexadecimal presentation Hexadecimal presentation Hexadecimal presentation Hexadecimal presentation

6. Activity 2(15) Breakdown each hexadecimal into 4 bits Breakdown each hexadecimal into 4 bits Why do we do this? Why do we do this? 8 4 2 1 8 4 2 1

7. Binary addition Same as denary, if a number > 9 we use a place value and carry a 1 to the column on the left Same as denary, if a number > 9 we use a place value and carry a 1 to the column on the left Rules: Rules: 0 + 0 =0 0 + 0 =0 0 + 1 = 1 + 0 = 1 0 + 1 = 1 + 0 = 1 1 + 1 = 10 (0 and carry 1(to the left)) 1 + 1 = 10 (0 and carry 1(to the left)) Add 2 digits at a time Add 2 digits at a time Carry over numbers to the side Carry over numbers to the side

8. 1011 + 1011 + 1001 1001 Can we cheat a little Can we cheat a little 0 + 0 = 0 0 + 0 = 0 0 + 1 = 1 0 + 1 = 1 1 + 0 = 1 1 + 0 = 1 1 + 1 = 10 (?) 1 + 1 = 10 (?) 1 + 1 + 1 = (1 and carry 1) 1 + 1 + 1 = (1 and carry 1)

9. Multiplication 0 x 0= 0 0 x 0= 0 0 x 1 = 1 0 x 1 = 1 1 x 0 = 0 1 x 0 = 0 1 x 1 = 1 1 x 1 = 1 0101 * 0101 * 0011 0011