The CPU

Question 1

What are the steps of the fetch-execute cycle?

Answer 1

• Fetch - get instruction
• Decode - work out what to do
• Execute - carry out the instruction
• Store - copy result to memory

Question 2

Define

RAM (Random-Access Memory)

Answer 2

Temporary memory which store instructions and values to be used by the CPU

Question 3

Define

Registers

Answer 3

Special memory locations in the CPU that can be accessed very fast. (E.g. Instruction Register (IR), the Program Counter (PC), and the Accumulator.)

Question 4

Define

Buses

Answer 4

The information highway for the CPU, which carry data between components. (E.g. Address, the data, and the control buses.)

Question 5

Define

Arithmetic/Logic Unit (ALU)

Answer 5

The number cruncher of the CPU, which performs all the mathematical calculations. Can add, subtract, multiply, divide, and perform other calculations on binary numbers.

Question 6

Define

Control Unit

Answer 6

This component is responsible for directing the flow of instructions and data within the CPU. The Control Unit is actually built of many other selection circuits such as decoders and multiplexors.