The CPU is the control center for a computer. It guides, directs & governs its performance. It is the brain of the computer.
CPU CONTAINS :
1. Arithmetic & Logical Unit
2. Control Unit
ARITHMETIC & LOGICAL UNIT
An Arithmetic and Logical Unit (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 is a combination of Arithmetic Unit & Logical Unit.
Arithmetic Unit performs all the arithmetic operations like addition , subtraction , multiplication & division performed on the operands.
For example :
a + b
a - b
a * B
a / b
Control Unit is most important part which controls all the internal as well as external functions in the computer.
THE MAIN FUNCTIONS PERFORMED BY THE CONTROL UNIT ARE :
1. It controls & guides the interpretation , flow & manipulation of all data & information.
2. It sends control signals until the required operations are done properly by ALU & memory.
3. It gets program instructions from memory & executes them one after another.
4. It controls the flow of data from input device to memory & from memory to output devices.