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WHAT: Understand how instructions are stored and executed in a computer system

HOW:

Activity 1 - Watch this video (twice if you need to)

Activity 2 - READ

The video above is for GCSE and A-Level students so its possible that you may find some of the concepts a little challenging. High level students should be able to state the principals of Von Neumann Architecture.

In simple terms...

The CPU is the brain of the computer and it processes instructions.

Instructions are stored in RAM (Random Access Memory)

The CPU gets the instruction...fetches it.

It then makes sense of it...decodes it.

Then the CPU carries out the instruction...executes it.

This process is called the Fetch-Execute Cycle.

Activity 3 - READ

Instructions aren't just stored in the computer's main memory (RAM). They are also stored in secondary storage. This is usually a computer hard drive but there are lots of other types of secondary storage.

RAM is known as volatile memory. This means that when the power is turned off, the instructions stored in it will be deleted.

Secondary storage is known as non-volatile memory. This means that when the power is turned off, the instructions in it are saved (providing you clicked save!).

RAM

Primary Storage (Main Memory)

Volatile

Deletes when power is off

HARD DRIVE

Secondary Storage

Non-Volatile

Saves when power is off

Activity 3

Investigate other types of secondary storage.

Find out:

  • What is the average cost?
  • Can the internal parts move?
  • How small can the storage device be?
  • What is the average storage capacity available?

Challenge investigation question:

  • HOW do the storage devices store the data?

CHECK:

EMBED:

1. Find out more about Von Neumann Architecture from this website.

2. Find out about Moore's Law from this website.

3. Create a physical model to interpret the workings of the CPU.

CLASSROOM IDEAS:

This might be a good time to introduce some simple robotics to the students. Can they get an LED to light up in a sequence? This will help them see how instructions, storage and output work.