Systems Architecture
Overview
Open a machine and there is remarkably little inside: a processor smaller than a postage stamp, some memory, a drive, and wires joining them. That is essentially the same list you would have found in the first stored program computers, and the arrangement has a name. Instructions and data live together in one memory, and a processor fetches those instructions one at a time and carries them out. Everything a computer has ever done is that loop, repeated very fast.
This lesson takes the machine apart. You will learn what each part of the processor does, what happens on each turn of the fetch, decode and execute cycle, and why three particular numbers, the clock speed, the number of cores and the size of the cache, are the ones printed on the box. Then you will meet the storage hierarchy: why a computer needs both memory and a drive, what makes one volatile and the other not, how magnetic, optical and solid state storage actually work, and where cloud storage and embedded systems fit into the picture.
Objectives
- Explain the Von Neumann architecture. Explain the role and operation of:
- main memory
- the following major components of a central processing unit (CPU):
- arithmetic logic unit
- control unit
- clock
- buses.
- Explain the effect of the following on the performance of the CPU:
- clock speed
- number of processor cores
- cache size.
- Understand and explain the Fetch-Execute cycle.
- Understand the differences between main memory and secondary storage.
- Understand the differences between RAM and ROM. Be able to explain the terms volatile and non-volatile. Understand why secondary storage is required. Be aware of different types of secondary storage (solid state, optical and magnetic).
- Explain the operation of solid state, optical and magnetic storage.
- Discuss the advantages and disadvantages of solid state, optical and magnetic storage.
- Explain the term ‘cloud storage’.
- Explain the advantages and disadvantages of cloud storage when compared to local storage. Understand the term ‘embedded system’ and explain how an embedded system differs from a non-embedded system.
Mind map
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Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Systems Architecture. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- What are the three stages of the fetch-execute cycle, in the correct order? A. Decode, fetch, execute B. Fetch, decode, execute C. Execute, fetch, decode D. Fetch, execute, decode Answer: B
- Which component of the CPU performs arithmetic and logical operations? A. The control unit B. The clock C. The arithmetic logic unit D. The bus Answer: C
- What is a bus? A. A collection of wires through which data is transmitted between components B. A program that manages memory C. A type of secondary storage D. A unit of clock speed Answer: A
- Which statement about RAM and ROM is correct? A. Both are volatile B. Both are non-volatile C. RAM is volatile and ROM is non-volatile D. RAM is non-volatile and ROM is volatile Answer: C
- Why is a solid state drive more suitable than a magnetic hard disk drive for a laptop? A. It stores more data for the same price B. It has no moving parts, so it uses less power and resists shock better C. It is the only type that is non-volatile D. It can be accessed directly by the CPU Answer: B
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