A Level CompSci Paper One Revision Quiz H446

What does the Control Unit (CU) do?

• Stores data fetched from memory

• Holds the address of the next instruction

• Performs arithmetic calculations

• Sends out control signals to other parts of the CPU

Which register holds the address in memory of the next instruction?

• Program Counter (PC)

• Current Instruction Register (CIR)

• Memory Address Register (MAR)

• Memory Data Register (MDR)

What is the function of the Arithmetic Logic Unit (ALU)?

• Performs calculations and logical operations

• Sends control signals to memory

• Coordinates CPU activity

• Stores the results of calculations

What does the address bus do?

• Provides a memory address to system memory or I/O devices

• Holds the most recently fetched instruction

• Sends control signals to perform read or write operations

• Transfers data between the CPU and memory

What is the first step in the fetch stage of the fetch-decode-execute cycle?

• The instruction on the data bus is loaded into the memory data register

• The control unit triggers a read signal down the control bus

• The program counter copies the address of the next instruction into the memory address register

• The control unit loads the address onto the address bus

What happens during the decode stage of the fetch-decode-execute cycle?

• The program counter is incremented by one

• The contents of the current instruction register are sent to the control unit

• The instruction is loaded into the memory data register

• The data is transferred to the accumulator

What is the effect of increasing the clock speed of a CPU?

• It allows the CPU to carry out more instructions per second

• It reduces the heat generated by the CPU

• It decreases the number of cores in the CPU

• It makes the CPU less efficient

What is the main advantage of using cache memory?

• It holds instructions or data that are frequently used

• It has a larger capacity than RAM

• It is slower than RAM

• It is cheaper than RAM

What is pipelining in CPU processing?

• A technique for executing multiple instructions simultaneously

• A technique for fetching an instruction while the prior one is being decoded

• A method for increasing the clock speed

• A way to store frequently used data

What is the main difference between Von Neumann and Harvard architectures?

• Von Neumann has separate memory for data and instructions

• Harvard architecture stores instructions and data together

• Von Neumann architecture has a single control unit and ALU

• Harvard architecture is easier to design and build