CPU Structure & Instruction Flashcards

CPU

The Central Processing Unit that controls all operations and processes instructions.Directs how data moves and tells other parts of the CPU what to do.

Control Unit (CU)

Directs how data moves and tells other parts of the CPU what to do.

Arithmetic Logic Unit (ALU)

Performs arithmetic calculations and logical operations.

Registers

Small, fast storage inside the CPU used to hold data and instructions temporarily.

Program Counter (PC)

Stores the address of the next instruction to be executed.

Instruction Register (IR)

Holds the current instruction being processed by the CPU.

Instruction Cycle

The sequence of steps the CPU follows to process an instruction.

Fetch Stage

The CPU retrieves the instruction from memory.

Decode Stage

The CPU interprets what the instruction means.

Execute Stage

The CPU carries out the instruction operation.

Memory Access Stage

Data is read from or written to memory if required.

Write Back Stage

The result of execution is stored back into a register.

Instruction Pipeline

A technique where multiple instruction stages run at the same time.

Pipelining

Improves CPU performance by overlapping instruction execution.

Pipeline Hazard

A problem that delays instruction execution in a pipeline.

Data Hazard

VOccurs when an instruction depends on the result of a previous instruction.

Control Hazard

Happens when the CPU makes a wrong decision in branch instructions.

Structural Hazard

Occurs when hardware resources are not enough for multiple instructions

RISC

Reduced Instruction Set Computer that uses simple and fast instructions.

RISC Characteristics

Uses fixed-length instructions and focuses on speed and efficiency.

Clock Cycle

The basic timing unit that controls CPU operation speed.

Throughput

The number of instructions completed in a given time.