ASCII

Binary Code

It's time for you to be the teacher

As a table, I want you to research what ASCII is and make notes (on scrap paper) ready to present to the class (and me!).

You COULD use the following to help you:

Shared > computing- ICT > Year 7 > Unit 1 > Lesson 7 > ASCII Resource

(10 minutes)

Task

Complete the binary worksheet tasks 1 and 2

And the other way around.......

(20 mins)

If you get stuck remember the 4 B's:

Brain - Have I already been told how to do this?

Book - Can I research/have i been given this information already?

Buddy - Can one of my peers help me?

Boss - I have tried all of the above so I need to ask my teacher

We need to use an extra digit!

Lets do a few more examples together on the board .....

Conversions

To convert from binary to denary we can draw a grid using powers of two.

You can see below that I have listed the number 1, 2, 4, 8, 16, 32, 64, 128 in reverse order

= 157

There are 10 types of people in the world, those that understand binary, and those that don't!

Binary to decimal conversion

To convert, you simply take a value from the top row wherever there is a 1 below, and then add the values together.

Some people find this funny because.....

Each 1 or 0 in binary is called a 'bit'. 8 'bits' make up a byte of data.

A nibble of data is 4 bits, in other words half a byte.

The number system we use is called denary - it has ten different characters 0-9. 'De' means ten in latin, 'bi' means two.

So we know that computers can only understand 1' and 0's.....

How then can I represent a number bigger than 1?

If there are less than 8 bits in your number add 0's

The above becomes 00000010

Tip - Think about what is different between the number 9 and the number 10

Letters in to Binary

ASCII Code

We are using 8 bits per character - 8 bits makes a .....?

ASCII stands for American Standard Code for Information Interchange

OBJECTIVES

1. Be able to understand and recognise binary data;

2. Know how to convert denary numbers into binary numbers

3. Be able to convert characters into binary numbers using ASCII code

Starter

As computers only understand binary we need to convert our letters into numbers. The ASCII code system has a number for each of the characters on our keyboard.

Task

Plenary Task

Complete worksheet 1 - ASCII and Binary task - use your ASCII grid to help you decode the answers.

Talk to me

Explain to your partner what ASCII is (and what it stands for) and why it is needed.

If you get stuck remember the 4 B's:

Brain - Have I already been told how to do this?

Book - Can I research/have i been given this information already?

Buddy - Can one of my peers help me?

Boss - I have tried all of the above so I need to ask my teacher

Complete the binary worksheet on your desk!

(5 mins)