Istruction set and/or hardware of the processor

Istruction set and/or hardware of the processor

The CPU

 

·         This is often described as the brain of the computer. Inside there are billions of transistors which builds the circuitry of the board

 

 

Fetching

 

·         Retrieves data and instructions for storage in registers. The address is placed in the address bus, and the data bus reads the memory location.

 

Decoding

 

·         Interprets the instruction by using the instruction set of the processor.

 

Executing

 

·         The final stage in the fetch Decode Execute cycle. Carries out the action which has just been decoded

 

The control unit

 

·         It maintains the hardware attached to the computer. It controls the input and output. It controls the flow of data within the CPU.

 

Random Access Memory

 

·         The CPU stores it data here. Also known as the Immediate Access Store and is the computers working memory

 

Arithmetic logic unit

 

·         It performs calculations and deal with logic

 

Clock speed

 

·         It means computers can do more than one thing at a time. Measured in cycles per second.

 

Cores

 

·         You can have multiple to increase the speed your computer can process information

 

word length

 

·         A fixed sized group of bits that are handled as a unit by the instruction set and/or hardware of the processor

 

Register

 

·         extremely fast speed temporary memory locations within the processor

 

Cache memory

 

·         Expensive high speed memory built into the processor itself reducing the distance data has to travel. Regularly accessed data is stored in Cache where possible

 

Von Neumann Architecture

 

·         Computer architecture whereby instructions and data are held in memory. Data then moves between the memory unit and the processor.

 

Memory Address Register (MAR)

 

·         A register that is used to hold the memory address that is to be accessed

 

Memory Data Register (MDR)

 

·         A register used to hold the instructions and data that is being sent to, or received from, memory

 

Program Counter (PC)

 

·         The part of the CPU responsible for tracking which instruction is to be processed next

 

Current Instruction Register (CIR)

 

·         Contains the current instruction being processed

 

Fetch-Execute Cycle

 

·         When the processor fetches data and instructions from memory, stores them in suitable registers and the each instruction is decoded before being executed.

 

Bus

 

·         Move data around the computer and send out control signals to make sure everything is properly synchronised, can be address, data or control

 

Main Memory

 

·         Where data and instructions are stored inside the Processor. They are stored in electronic digital form.