CENTRAL PROCESSING UNIT

 

DEFINITION OF CENTRAL PROCESSING UNIT (CPU)

The central processing unit (CPU) is the portion of a computer system that executes the instruction of a computer program and it is primary element carrying out the functions of the computer. The central processing unit carries out each instruction of the program in sequence, perform the basic arithmetical, logical and input/output operations of the system.

The CPU can be found on the motherboard, all the functions of the CPU are stored in a component called the Chip.

- Components of the CPU.

The CPU consists of two main units namely;
1. Arithmetic Logic Unit (ALU)
2. Control Unit (CU)

FUNCTIONS OF THE CENTRAL PROCESSING UNIT COMPONENTS.

1. Arithmetic Logic Unit (ALU): An ALU is a digital circuit that performs arithmetic and logical operations. The ALU is a fundamental building block of the Central Processing Unit (CPU) of a computer. ALU performs the following functions.

1. It performs the mathematical operations such as Addition (+), subtraction(-), multiplication(x), division(÷) and so on.

2. The logic unit of the ALU is concerned with logical operations such as comparison Greater than (>), Less than (<), Equal to (=) and bit wise logic such as AND, OR, NOT, XNOR and so on.

2. Control Unit (CU): the Control Unit is an important component of the CPU. It acts like the supervisor of the computer. It Controls and Co-Ordinates all the activities of the computer system. It also maintains the order of traffic and data flow in the computer system.

The Control Unit performs the following basic functions on instructions.

1. It fetches instruction from the main memory

2. It decodes instruction; meaning it interprets instruction that was fetched.

3. It execute instruction; CU controls the execution of instruction in the computer system.

4. Storing results: Control Unit sends the results to the memory, the process of writing result to a specified memory location is called Storing. The CU ensures the output(s) gotten from the execution of an instruction are stored in the memory.

The collections of these four (4) functions together is what we referred to as Machine Cycle or Instruction Cycle of the CPU.

ASSIGNMENT

1. Define the term computer memory.
2. Describe the two types of computer memory that we have.
3.  Differentiate them; state two differences between the two types of memory.