Computer Architecture

Watch the video and make notes. You can pause the video at any time.

Keywords 🗝️ 

architecture, Von Neumann, fectch, decode, execute, address, CPU, main memory (RAM)

Summary 📝 

Computer architecture is all about how computers are built and how their main parts work together. At the heart of a computer is the CPU (Central Processing Unit), often called the “brain” of the computer. The CPU has key components: the Control Unit (CU), the Arithmetic Logic Unit (ALU), and registers. These all work together to fetch, decode and execute instructions. The architecture covered in GCSE is based on the Von Neumann model, where data and instructions are stored in the same memory. You'll also learn how buses (data, address and control) move information around the computer. Understanding these basics helps you see how software runs and how performance can be improved.

Computers store both programmes and data together in main memory (this is the Von Neumann model).

The CPU uses a fetch‑decode‑execute cycle to run instructions step by step.

Key learning Points 📌

The CPU contains key parts:

• Control Unit (CU): fetches and decodes instructions.

• Arithmetic Logic Unit (ALU): does calculations and makes decisions.

• Clock: keeps everything in step, using pulses.

• Registers: very small, fast memory inside the CPU for temporary data.

• Buses: groups of wires to move data, addresses, and control signals around.

These parts together allow the CPU to read and run instructions stored in memory.