CPU + Computer Architecture

CPU

Central Processing Unit; the processor that executes program instructions and performs calculations.

CPU architecture

The design and organization of a processor, including its instruction set, registers, datapath, and how it executes instructions.

ALU

Arithmetic Logic Unit; performs arithmetic operations and logical comparisons.

Control unit

CPU component that directs the execution of instructions and controls the movement of data.

Register

Very small, extremely fast storage located inside the CPU.

Datapath

The CPU components and connections through which data travels while instructions are executed.

Instruction set architecture (ISA)

The set of instructions and rules that software uses to communicate with a processor.

ARM

A widely used processor architecture based on a reduced instruction set.

LEGv8

A simplified teaching version of the ARMv8 instruction set used to learn computer architecture.

Machine language

Instructions represented in binary that the CPU can directly execute.

Assembly language

Human-readable representation of machine instructions using short commands such as ADD, SUB, and LDUR.

Opcode

The portion of an instruction that specifies which operation the CPU should perform.

Operand

The data, register, or memory location that an instruction operates on.

Fetch

The CPU retrieves the next instruction from memory.

Decode

The CPU determines what the fetched instruction means and what resources it needs.

Execute

The CPU performs the operation specified by the instruction.

Fetch-decode-execute cycle

The repeating process the CPU uses to retrieve, interpret, and execute program instruction