[4.0] Processor Technology

This primary component of the CPU moves data and instructions between main memory and registers

This primary component of the CPU performs all computation and comparison operations

This primary component of the CPU is the storage that holds inputs and outputs for the ALU.

How does the CPU execute the programs?

• The ALU reads instructions directly from primary storage, executes them, and stores the results in secondary storage.

• The control unit reads the first instruction from primary storage, stores it in a register, reads input (if needed), signals the ALU to perform operations, and executes instructions sequentially until completion.

• The CPU's registers fetch instructions, process data directly from I/O devices, and store final results only in secondary storage.

• The CPU executes instructions by fetching them from secondary storage, performing operations directly in the ALU, and sending data to I/O devices without intermediate steps.

Answer explanation

Control unit will read first instruction, stores instruction in register, tells ALU what to do and where to get/put input/output. This process continues until final instruction is executed.

RECALL: Control unit handles executing instructions to move data to memory , I/O devices or secondary storage

In this CPU action, data inputs are prepared for transformation into data output.

• Execute Cycle

• Fetch Cycle

In this CPU action, transformation to data output takes place and data is stored.

• Execute Cycle

• Fetch Cycle

Which of the following correctly describes the fetch cycle in a CPU?

• The fetch cycle involves fetching instructions from secondary storage, combining data inputs, and executing instructions immediately without separating components.

• During the fetch cycle, the CPU reads multiple instructions simultaneously, stores them in a single register, and processes all data inputs at once.

• The CPU fetches an instruction from primary storage, increments a pointer to the next instruction, separates the instruction into components (instruction code and data input), and stores each component in separate registers.

Answer explanation

1. 1. fetch instruction

2. 2. increment pointer to point to next instruction

3. 3. separate instruction into instruction code and data input

4. 4. store components in separate registers

Which of the following describes the execution cycle in a CPU?

• During the execution cycle, the CPU combines instruction code and data inputs directly from memory without using registers and sends the result to the ALU for storage.

• The CPU retrieves the instruction code and data inputs from registers, processes the inputs through internal circuits for transformations (e.g., addition, subtraction), and stores the result in a register.

• The execution cycle involves retrieving instructions from secondary storage, processing them through the control unit, and storing results directly in memory.

• The CPU retrieves instruction code from primary storage, reads data inputs from I/O devices, performs transformations, and stores results directly in secondary storage.

An ________ is a command to the CPU to perform primitive processing functions on specific data inputs, represented as a bit string logically divided into a number of components. It is the LOWEST-LEVEL COMMAND that software can direct a processor to perform.

An instruction has two components. What are they?

• Opcode and Operand

• Instruction Code and Data Storage Address

• Command Type and Memory Pointer

Answer explanation