components of the CPU

Question 1

What is the function of the control unit (CU)?

Answer 1

-fetches program instructions from main memory one at a time
-and decodes them
-and directs the operations of the other parts of the system to execute them.

Question 2

What is the function of the arithmetic logic unit (ALU)?

Answer 2

performs arithmetic and logic operations on data.

Question 3

What is the function of the clock?

Answer 3

an electronic unit that synchronises related components by generating pulses at a constant rate.

Question 4

What is the function of the cache?

Answer 4

small amount of very fast memory typically located very close to CPU or actually inside it.
-provides fast access to frequently used instructions and data

Question 5

What is the function of the address bus?

Answer 5

holds the address of the memory location that the CPU will read from or write to.
-The number of wires in this bus (the bandwidth) determines how much addressable memory there is .

Question 6

Is the address bus uni or bi directional

Answer 6

Unidirectional

Question 7

what is the function of the data bus?

Answer 7

Transfers program instructions and data between memory and CPU

Question 8

Why is the data bus bidirectional?

Answer 8

The CPU needs to be able to read program instructions and data from memory and write the results of operation to memory.

Question 9

What is the function of the control bus?

Answer 9

Carries signals between the CPU and other parts of the computer system.

Question 10

Is the control bus uni or bidirectional?

Answer 10

Bidirectional

Question 11

What is the function of the program counter?

Answer 11

holds the address of the next instruction to be executed

Question 12

What is the function of the memory address register (MAR)?

Answer 12

Holds the address in memory which data or an instruction needs to be read from or written to.

Question 13

What is the function of the memory data register?

Answer 13

Holds either data or an instruction which has been fetched from memory or is about to be written back to memory.

Question 14

What is the function of the accumulator

Answer 14

Set of general purposes registers which the CPU can utilize for different functions
-temporary values may be stored here before being written to and from memory
-depending on the CPU architecture or the number of different registers in the accumulator.