Fetch-Decode-Execute Cycle Vocabulary & Definitions

What is the 'brain' of the computer that processes instructions?

• CPU (Central Processing Unit)

• RAM (Random Access Memory)

• Hard Disk Drive

• Monitor

Answer explanation

The CPU (Central Processing Unit) is known as the 'brain' of the computer because it processes instructions and performs calculations, making it essential for executing programs and managing tasks.

The continuous process the CPU uses to run programs is called the _________.

• Fetch-Decode-Execute Cycle (FDE Cycle)

• Random Access Memory (RAM)

• Binary Search Algorithm

• Input/Output Process

Answer explanation

The continuous process the CPU uses to run programs is known as the Fetch-Decode-Execute Cycle (FDE Cycle). This cycle involves fetching instructions, decoding them, and executing them, making it essential for program execution.

Which register holds the address of the next instruction to fetch and increments after each fetch?

• Program Counter (PC)

• Accumulator (ACC)

• Instruction Register (IR)

• Memory Address Register (MAR)

Answer explanation

The Program Counter (PC) holds the address of the next instruction to be fetched and increments after each fetch, ensuring the CPU processes instructions in the correct sequence.

What does MAR stand for in the context of CPU registers?

• Memory Address Register

• Main Arithmetic Register

• Machine Access Register

• Memory Allocation Register

Answer explanation

MAR stands for Memory Address Register, which is a CPU register that holds the memory address of data that needs to be accessed. This makes it the correct choice, as the other options do not accurately describe this function.

What does the Memory Data Register (MDR) temporarily hold?

• The data or instruction read from or written to memory.

• The address of the next instruction to be executed.

• The status flags of the processor.

• The opcode of the current instruction.

Answer explanation

The Memory Data Register (MDR) temporarily holds the data or instruction that is being read from or written to memory, making it essential for data transfer between the CPU and memory.

What does the Current Instruction Register (CIR) / Instruction Register (IR) hold?

• The instruction currently being decoded/executed.

• The address of the next instruction to be executed.

• The data currently being processed.

• The status of the last operation performed.

Answer explanation

The Current Instruction Register (CIR) holds the instruction currently being decoded or executed, making it essential for the CPU to know what operation to perform next.

What does the Accumulator (ACC) hold?

• The result of ALU operations.

• The address of the next instruction.

• The contents of the program counter.

• The opcode of the current instruction.

Answer explanation

The Accumulator (ACC) is a register that holds the result of operations performed by the Arithmetic Logic Unit (ALU). It does not store addresses or opcodes, making 'The result of ALU operations' the correct choice.

What is the function of General Purpose Registers?

• Temporary data storage during execution.

• Permanent storage of programs.

• Controlling the power supply to the CPU.

• Managing network connections.

Answer explanation

General Purpose Registers are used for temporary data storage during the execution of instructions. They hold data that the CPU needs to process, making them essential for efficient computation.

What does the Control Unit (CU) manage?

• The FDE cycle.

• The arithmetic operations.

• The storage of data.

• The input and output devices.

Answer explanation

The Control Unit (CU) manages the Fetch-Decode-Execute (FDE) cycle, coordinating the operations of the CPU by fetching instructions, decoding them, and executing them in the correct sequence.

What does the Control Unit (CU) send to direct data flow and operations?

• Control signals.

• Data packets.

• Power supply.

• Clock pulses.

Answer explanation

The Control Unit (CU) sends control signals to direct the flow of data and operations within the CPU, ensuring that the correct processes are executed at the right time.