IGCSE Computer Science: CPU

What does CPU stand for?

• Control Processing Unit
• Central Programming Unit
• Central Processing Unit
• Computer Processing Unit

Answer explanation

The CPU stands for Central Processing Unit, the main component responsible for executing instructions in a computer. (Ch. 4, p. 45)

What is the main function of the CPU?

• Store data
• Execute instructions
• Manage input devices
• Display output

Answer explanation

The CPU's primary role is to execute instructions from programs by performing the fetch-execute cycle. (Ch. 4, p. 45)

What does ALU stand for?

• Arithmetic Logic Unit
• Advanced Learning Unit
• Automatic Logic Unit
• Arithmetic Load Unit

Answer explanation

The ALU (Arithmetic Logic Unit) performs arithmetic and logical operations within the CPU. (Ch. 4, p. 47)

Which component of the CPU performs calculations?

• Control Unit
• ALU
• Registers
• Memory Unit

Answer explanation

The ALU handles all arithmetic and logical operations, such as addition and comparisons. (Ch. 4, p. 47)

What does CU stand for in the context of the CPU?

• Central Unit
• Control Unit
• Computing Unit
• Cache Unit

Answer explanation

The CU (Control Unit) directs the operation of the CPU, managing the fetch-execute cycle. (Ch. 4, p. 48)

Which part of the CPU directs the flow of data?

• ALU
• Control Unit
• MAR
• MDR

Answer explanation

The Control Unit coordinates data flow and instruction execution within the CPU. (Ch. 4, p. 48)

What does MAR stand for?

• Memory Access Register
• Memory Address Register
• Main Access Register
• Memory Allocation Register

Answer explanation

The MAR (Memory Address Register) holds the address of the memory location to be accessed. (Ch. 4, p. 47)

What is the role of the MAR in the CPU?

• Stores data
• Holds memory address
• Performs calculations
• Executes instructions

Answer explanation

The MAR stores the address of the memory location the CPU needs to read from or write to. (Ch. 4, p. 47)

What does MDR stand for?

• Memory Data Register
• Main Data Register
• Memory Direction Register
• Machine Data Register

Answer explanation

The MDR (Memory Data Register) holds the data being transferred to or from memory. (Ch. 4, p. 47)

What does the MDR do during the fetch-execute cycle?

• Stores the address
• Holds fetched data
• Performs logic operations
• Controls the ALU

Answer explanation

The MDR temporarily holds the data fetched from memory or to be written to memory. (Ch. 4, p. 47)