Buses and Instructions

Question 1

What is the Address Bus?

Answer 1

The address bus is used to get the location/destination of where the data is meant to go to.

Question 2

What is the Data Bus?

Answer 2

Transfers data between the processor and the memory

Question 3

What is the Control Bus?

Answer 3

This is a bi-directional bus that sends signals to the registers, data bus and the address bus.

Question 4

What are the three steps to an Instruction?

Answer 4

Fetch, Decode, Execute

Question 5

Fetch?

Answer 5

The processor fetches the program’s next instruction from memory. The instruction will be stored at a memory address and will contain the instruction in binary code.

Question 6

Decode?

Answer 6

The processor works out what the binary code at the address means and turns it into readable language for the computer to understand.

Question 7

Execute?

Answer 7

The processor carries out the instruction which may involve reading an item of data from memory, performing a calculation, or writing data back into memory.

Question 8

What are Interrupts?

Answer 8

This is a signal sent to the processor from a program, or from an external device, such as a hard disk, printer or keyboard.