CPU Operations and Memory Lecture Notes

Vocabulary flashcards based on lecture notes detailing the Fetch-Decode-Execute cycle and types of CPU memory/registers.

Fetch

The phase where the CPU starts by retrieving instructions from the main memory and loading them one at a time into its registers.

Instruction Register (IR)

A register that holds the data acquired during the fetch step because it is considered as an instruction that is being executed by the CPU.

Program Counter (PC)

A register that holds the memory address of the next instruction to be fetched from main memory.

Decode

The process of translating an instruction into signals that can trigger the appropriate actions within the CPU, where the control unit breaks the instruction into opcode and operands.

Opcode

A part of the instruction that indicates the type of operation to be performed such as addition, subtraction, data transfer or control operations like jumps.

Operands

The part of the instruction that specifies the data to be used or the addresses of the data involved.

Execute

The final stage where the CPU carries out the decoded instruction using its ALU and other CPU components.

Special-Purpose Memory

High-speed storage locations found inside the CPU, I/O devices or between the CPU and RAM that store frequently used instructions for quick access.

Cache memory

A high-speed temporary memory located inside or close to the CPU used to store frequently accessed data and instructions to reduce processing delays.

Registers

High speed, temporary memories in the CPU used to temporarily hold data, instructions and addresses during processing.

Accumulator

A register that stores results of arithmetic and logic operations temporarily before they are used or stored in the main memory.

Secondary storage

Long-term, non-volatile storage that does not lose its content even when the power is turned off.