1. Introduction to Microprocessor

Definition:

• “The microprocessor is a multipurpose, clock driven, register based, digital-integrated circuit which accepts binary data as input, processes it according to instructions stored in its memory, and provides results as output.”
  • “Microprocessor is a computer Central Processing Unit (CPU) on a single chip that contains millions of transistors connected by wires.” Introduction:
  • A microprocessor is designed to perform arithmetic and logic operations that make use of small number-holding areas called registers.
  • Typical microprocessor operations include adding, subtracting, comparing two numbers, and fetching numbers from one area to another.
• Components of Microprocessor
  • Microprocessor is capable of performing various computing functions and making decisions to change the sequence of program execution.
  • The microprocessor can be divided into three segments as shown in the figure, Arithmetic/logic unit (ALU), register array, and control unit.
  • These three segment is responsible for all processing done in a computer

Arithmetic and logic unit (ALU)

• It is the unit of microprocessor where various computing functions are performed on the data.
• It performs arithmetic operations such as addition, subtraction, and logical operations such as OR,AND, and Exclusive-OR.
• It is also known as the brain of the computer system.

Register array

• It is the part of the register in microprocessor which consists of various registers identified by letters such as B, C, D, E, H, and L.
• Registers are the small additional memory location which are used to store and transfer data and programs that are currently being executed.

Control unit

• The control unit provides the necessary timing and control signals to all the operations in the microcomputer.
• It controls and executes the flow of data between the microprocessor, memory and peripherals.
• The control bus is bidirectional and assists the CPU in synchronizing control signals to internal devices and external components.
• This signal permits the CPU to receive or transmit data from main memory.