Y10 U1L1 - CPU Architecture Quiz

What is the main purpose of the CPU?

• To process instructions

• To control output devices

• To store data

• To manage input devices

Answer explanation

The main purpose of the CPU is to process instructions. It executes commands from programs, making it the central component for computing tasks, unlike the other options which involve peripheral management.

Which register holds the address of the next instruction to be executed?

• Memory Address Register (MAR)

• Memory Data Register (MDR)

• Accumulator (ACC)

• Program Counter (PC)

Answer explanation

The Program Counter (PC) holds the address of the next instruction to be executed in a CPU. It increments after each instruction fetch, ensuring the CPU knows where to go next in the instruction sequence.

What does the Control Unit (CU) do?

• Stores data temporarily

• Coordinates CPU activities

• Performs arithmetic operations

• Fetches instructions from memory

Answer explanation

The Control Unit (CU) coordinates CPU activities by directing the operation of the processor, managing the flow of data between the CPU, memory, and input/output devices, making it essential for overall system functionality.

Which component of the CPU performs arithmetic and logic operations?

• Control Unit

• Cache

• Arithmetic Logic Unit (ALU)

• Registers

Answer explanation

The Arithmetic Logic Unit (ALU) is the component of the CPU responsible for performing all arithmetic and logic operations, making it the correct choice for this question.

What is the function of the Memory Address Register (MAR)?

• Stores the current instruction

• Holds the address of the instruction to be executed

• Stores the result of an instruction

• Fetches data from the cache

Answer explanation

The Memory Address Register (MAR) holds the address of the instruction to be executed next. It does not store the instruction itself or the result of an instruction, nor does it fetch data from the cache.

What is the role of the Accumulator (ACC)?

• Decodes instructions

• Fetches instructions from memory

• Stores the result of arithmetic and logic operations

• Holds the address of the next instruction

Answer explanation

The Accumulator (ACC) is primarily responsible for storing the results of arithmetic and logic operations performed by the CPU, making it essential for processing data.

Which of the following is NOT a register in the CPU?

• Data Bus

• Memory Data Register (MDR)

• Memory Address Register (MAR)

• Program Counter (PC)

Answer explanation

The Data Bus is not a register; it is a communication pathway for transferring data between components. In contrast, the Memory Data Register (MDR), Memory Address Register (MAR), and Program Counter (PC) are all registers within the CPU.

What does the fetch-execute cycle consist of?

• Fetch, Store, Execute

• Input, Process, Output

• Store, Process, Output

• Fetch, Decode, Execute

Answer explanation

The fetch-execute cycle consists of three main stages: Fetch (retrieve the instruction), Decode (interpret the instruction), and Execute (perform the instruction). Thus, the correct answer is 'Fetch, Decode, Execute'.

What is the purpose of the Cache in the CPU?

• To store permanent data

• To speed up data access

• To manage input devices

• To execute instructions

Answer explanation

The purpose of the Cache in the CPU is to speed up data access by storing frequently used data and instructions closer to the processor, reducing the time it takes to retrieve them compared to accessing main memory.

Which of the following is a characteristic of the Von Neumann architecture?

• No use of registers

• Only one instruction can be executed at a time

• Instructions and data stored in the same memory

• Separate memory for instructions and data

Answer explanation

The Von Neumann architecture is characterized by storing both instructions and data in the same memory space, allowing for a simpler design. This distinguishes it from architectures with separate memory for instructions and data.