Logic Gates to Processors

Introduction

In this unit you learn how computers are constructed. From the underlying logic gates (built from transistors that control electrons with quantum mechanics) to the larger architecture that connect different parts of a computer. You will study how a computer runs code at the lowest level - Machine code and the Fetch-Decode-Execute Cycle.

dot points

Logic Gates

• use logic gates to create electronic circuits
• understand and define the functions of NOT, AND, OR, NAND, NOR and XOR (EOR) gates, including the binary output produced from all the possible binary inputs
• draw truth tables and recognise a logic gate from its truth table
• recognise and use the following standard symbols used to represent logic gates:
  • NOT, AND, OR, NAND, NOR, XOR
• produce truth tables for given logic circuits
• produce a logic circuit to solve a given problem or to implement a given written logic statement

Computer architecture

• show understanding of the basic von Neumann model for a computer system and the stored program concept (program instructions and data are stored in main memory and instructions are fetched and executed one after another)
• describe the stages of the fetch-execute cycle, including the use of registers and buses