Structure and function -Exam QUestions

Question 1

Describe the 3 buses that connect the CPU to the rest of the computer

Answer 1

Control bus – transmits control signals from the control unit to other parts of the computer
Data bus – Carries the data
Address bus – carries the location address to memory

Question 2

Explain the need for the PC

Answer 2

Needed to store the address of the next instruction
Value is then sent to the MAR
After value is sent it is then incremented

Question 3

Explain the need for the MAR

Answer 3

Contains the address of the instruction/data to be accessed in memory
Receives the instruction from the PC

Question 4

Explain the need for the MDR

Answer 4

Contains the instruction/data that has been accessed from memory
Data is referenced by the MAR
Instructions are sent to CIR
Acts as a buffer

Question 5

Describe the use of the ACC

Answer 5

Temporary storage for data being processed/ during calculations
I/O in the processor used as a buffer /gateway

Question 6

Describe the role of the CU in the processor

Answer 6

Decodes instructions
Sends control signals to coordinate movement of data
Controls buses

Question 7

How does a faster clock speed improve CPUs performance

Answer 7

More FDE cycles per second
Therefore more instructions per second
So the programs takes less time to run

Question 8

Explain an advantage of using CISC instead of RISC

Answer 8

Programs run faster due to fewer instructions

Question 9

Explain the effect of using a coprocessor when carrying out complex calculations

Answer 9

The coprocessor performs the calculations so they are processed faster when using floating point arithmetic

Question 10

Describe the features of the Von-Neumann architecture

Answer 10

Single control unit
One instruction at a time
Uses FDE cycle
Instructions and data stored in same memory unit