The first microprocessor was intel 4004, it was invented by the intel company in the year 1971. As the human body is controlled by the brain the same way a computer system is controlled by the CPU/Processor. CPU/Processor sometimes it’s called the brain of the computer. The main purpose of the CPU is when you click any program or application to start a program, you’re sending an instruction to the CPU. CPU has computing and decision-making power so it is also known as the brain of the computer. A computer's CPU handles all instructions it receives from hardware and software running on the computer. The CPU also communicates with the output/input device and it also communicates with the memory and storage devices. CPU is the main part of the computer that performs all its activities. CPU process a large amount of information at a very high speed and produce accurate results. CPU/Processor is located inside of a computer case.




Components of CPU/Processor

  • Arithmetic and Logic Unit
  • Control Unit
  • Registers
  • Cache
  • Internal Buses

Arithmetic Unit: -

Arithmetic units perform arithmetic operations such as addition, subtraction, multiplication, division and comparison.

Logic Unit: - 

The logic unit performs operations such as AND, OR, NOT, etc. on the data contained in the registers.

Control Unit: -

Control unit control commands and controls the operations of the computer system base on the instructions in the program by executing them in proper order.

Control unit component

  • Instruction registers
  • Instruction decoder
  • Timing and control logic

Registers: - 

Registers are small, high-speed temporary storage inside the CPU/Processor. CPU/Processor uses this temporary memory to store data or instructions during processing. Registers also pass that information or data to the other parts of the CPU or main memory during processing. CPU contains several registers each register has its own pre-defined function. 

The common use of CPU registers

  • Instruction Register
  • Accumulator Register
  • Data Register
  • Program Counter Register 
  • Memory Address Register

Cache Memory: - 

Cache memory is a high-speed small amount of memory inside the microprocessor. Cache memory stores data or information that is frequently required by the CPU/Processor means it keeps an active portion of the main memory.

Internal CPU Buses:- 

The buses found inside the CPU/Processor are known as internal buses. CPU/Processor is connected with all the devices through buses.

There are Three Types of Buses 

  • Address Bus
  • Data Bus
  • Control Bus

The extension of these three buses is also available outside the CPU to communicate all the connected components with the computer.