1. Candidates should be able to:
Convert positive denary whole numbers (0-255) into 8-bit binary numbers and vice versa
Add two 8-bit binary integers and explain overflow errors which may occur
Convert positive denary whole numbers (0-255) into 2-digit hexadecimal numbers and vice versa.
Convert between binary and Hex equivalents of the same number
Explain the use of Hex numbers to represent binary numbers

2. Hexadecimal Numbers
Hexadecimal is the name given to numbers using base 16
Decimal numbers 10 – 15 are represented using letter A – F
16 values so base 16

3. Hexadecimal
Used in computing as it is a much shorter way of representing a byte of data. Binary data = 8 digits, Hexadecimal data = 2 digits
E.G = FF
Largest byte value is 255 and hexadecimal can represent up to that number

4. Binary to Hexadecimal
HEX is used to express binary numbers in a more compact form
HEX numbers run from Zero to F (15 decimal)
15 decimal = 1111 (nibble) = F (Hex)

5. 11011110 = DE (Hex) Binary to Hexadecimal
Example 1 – as Hex number
Split number into 2 nibbles (1101…..1110)
Convert number to decimal
1101 = 13
1110 = 14
Convert number to Hex
13 = D
14 = E
= DE (Hex)

6. 1110 0011 (E3 in binary) Hexadecimal to Binary
Example 1 – E3 as binary number
Take 1st Hex digit – convert to binary nibble
3 Hex = 3 decimal = 0011 binary
Take 2nd hex digit – convert to binary nibble
E Hex = 15 decimal = 1110 binary
Put the 2 nibbles together
(E3 in binary)

7. Decimal to Hexadecimal conversion
Example 1 – 55 as Hex number
Put headings etc
Write out binary number (55)
Split into 2 nibbles: 0011…0111
0011 = 3
0111 = 7
55 = 37 (Hex)

8. Decimal to Hexadecimal conversion
Example 2 – 17 as Hex number
Put headings etc
Write out binary number (17)
Split into 2 nibbles: 0001…0001
0001 = 1
17 = 11 (Hex)

9. Have a go at these OR – MUCH HARDER
OR – MUCH HARDER

10. Have a go at the Test