What is microprocessor and explain the parts of microprocessor using block diagram?

Block diagram

Working:

· CPU consists of three basic units: control unit, Arithmetic Logical Unit (ALU) and memory unit.

· Input is given through the input devices to CPU.

· Control unit controls communication within ALU and memory unit.

· Decides which circuit is to be activated.

· For reading instruction it uses Fetch-execute mechanism.

· Control unit gets instruction from memory.

· Control unit decides what to do of that instruction and transfers it to the ALU.

· ALU performs various arithmetic operations like addition, subtraction, multiplication, division and logical operations like AND, OR, NOT, NAND etc. on that instruction.

· Results of ALU are stored in the memory or resistor for its further operations.

· After completing the instruction, stored results are passed to the output devices.

· To synchronize all these operations CPU uses its own system clock.