Objectives for this topic

By the end of this topic, you should be able to:

describe the internal parts and registers of a CPU;
describe both high and low-level languages;
describe an assembly language instruction and its machine-code equivalent.

You might also be able to:

identify scenarios where high and low-level languages are more or less appropriate.

Introduction

We have become somewhat spoilt with modern computers: compared to the computers being used 20 or 30 years ago, they have enormous amounts of memory and cache, tremendous clock speeds and huge storage. However, whether you are working with microcontrollers (which don’t have the benefits) or trying to get the most out of a modern processor, understanding what is happening inside the CPU and how low-level languages operate directly on the hardware is a key skill. It is also a really good idea to know how things work. You can drive a car without knowing how an internal combustion engine works, but if you do understand how it works, your affinity with the machine increases: the same is true with computers.

Working through your coursebook

Read pages 14-15 in your Computing Stage 9 book.

Read the Practise task on pages 14-15; there is nothing to actually do in this box, so just make notes as usual.
Complete the Practise task on page 15.

DOWNLOAD - Understanding the CPU here

If needed, watch this video on accessing worksheets:

Make sure that you understand the keywords described on pages 14-15. Add them to your cram.com flashcards.

Read pages 16-17 in your Computing Stage 9 book.

Read the Learn box on pages 16-17; pay particular attention to the difference between an Opcode and Operand.
Make sure that you understand the keywords described on pages 16-17. Add them to your cram.com flashcards.
Complete the Practise task on page 17.

Review

Reflect upon the four pages you have just covered. In your notes, summarise:

what you have learnt;
what you already knew;
what surprised you;
what you are curious to know more about.

Support activity for this topic

Watch this video for more support on making an infographic:

Extension activity for this topic

Watch this video to learn a bit more depth on machine code instructions and how they are split: