ALU, CU, Registers and buses

Question 1

ALU

Answer 1

Arithmetic Logic Unit
Performs calculations
Deals with Logic and comparisons

Question 2

CU

Answer 2

Control Unit

• sends signals to coordinate how the processor works
• controls how data moves between parts of the CPU

Question 3

What is a register

Answer 3

• Memory locations within the processor
• work at fast speeds
• used to control the fetch decode execute cycle

Question 4

PC

Answer 4

Program Counter

- Stores the address of the next instruction

Question 5

MAR

Answer 5

Memory Address Register

-Stores the Address or data which are to fetched from or sent to the memory

Question 6

MDR

Answer 6

Memory Data Register

-Stores the data which is to be sent to or fetched from the memory

Question 7

CIR

Answer 7

Current Instruction Register

-Stores the actual instruction which is being decoded and executed

Question 8

Accumulator

Answer 8

Stores the results of calculations made by the ALU

Question 9

Address Bus

Answer 9

Carries the address of the instruction or data.

• from processor to memory
• This bus only travels in one direction as only the processor can send an address to the memory

Question 10

Data Bus

Answer 10

Carries data between the processor and the memory

• Bi-directional
• Can also carry instruction from the memory to the processor

Question 11

Control Bus

Answer 11

Sends control signals between the processor and its components
-Bidirectional