Booklet
(A level Revision Booklet)
, Contents Page
Types of data……………………………………………………………………………………………………….1
Twos complement …………………………………………………………………..……………………….1-2
ASCII…………………………………………………………………………………………..………………………2
How data is represented…………………………………………………………..……………………….3-4
Exercise 1A questions………………………………………………………………….…………………….4
Floating point ……………………………………………………………………………..……………………5
Image conversion …………………………………………………………………………..………………..6
Audio conversion ……………………………………………………………………………………………..7
Binary logic gates ……………………………………………………………………………..……………..8
Questions
Exercise 2………………………………………………………………………………….……………….9
Exercise 3………………………………………………….……………………………..………………..9
Answers……………………………………………………………………………………..………………….10
Logic gate circuits ……………………………………………………………….……………………….11-14
Bibliography………………………………………………………………………………………………….15
, Types of data
Computers operate in various ways according to what data is implemented into it. There are
different data formats for the computer to read. Numeric data is a type of data the computer reads.
This is one of the main types of data often used. Numeric data is just data that simply means
numbers, but these numbers come in different forms.
Integers- this is a whole number which doesn’t contain any decimal or fraction parts. Integers can
also be both positive and negative
Examples 52 46 56000 -13354 -26466
Real Numbers- numbers which can be placed on a number line is a considered a real number. Real
numbers are whole numbers, integers, contain decimal/fraction parts and can be positive or
negative.
Examples 74 1.32 -3 -4.5342
Alphanumeric Data- this type of numeric data is made up of both letters and numbers.
Alphanumeric data can also include symbols.
Examples SIMPLE Master32
Boolean data- also known as logical data, this data represents yes/no. This data only has two values
TRUE or FALSE.
Twos Complement
Adding positive and negative numbers can be frustrating and can require a lot of working
out. With twos complement, adding positive and negatives numbers can be much easier and
straightforward.
Example
-7 in an 8 bit 2’s complement format. Follow these steps
1. Show the number as if it was a positive 8 bit number, so this is 00000111
2. Keep the rightmost 1 then flip all the bits on the left
00000111
After keeping the rightmost 1 and flipping all on the left should give you an outcome like
this
11111001
So 11111001 is -7 in twos complement format.
This is how you add 9 and -7. The answer should be 2. +9 is 00001001
00001001
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