Definition and Fundamentals of Computer Organization
A modern computer is really quite a complex system- in the sense that its rich functionality is achieved through the proper interconnection and coordinated operation of a number of separate subsystems, such as processor, memory, keyboard, disk drive, display and so on. At a top level, a computer consists of CPU (central processing unit), memory, and I/O components, with one or more modules of each type. These components are interconnected in some fashion to achieve the basic function of the computer, which is to execute programs.
A computer program is a sequence of instructions for the computer . The data that are manipulated by the program constitute the database. CPU for arithmetic and Logic unit for manipulating data, Storing data , control circuits for fetching and executing instructions. RAM for storage of data and instructions.
Computer Organization is concerned with the way the hardware components operate and the way they are connected together to form the computer system. The various components are assumed to be in place and the task is to investigate to organizational structure to verify that the computer parts operate is intended.
There are four main functions of a computer::
- Data processing
- Data Storage
- Data Movement
MAIN STRUCTURAL BLOCKS/PARTS:
Central Processing Unit (CPU): Controls the operation of the computer and performs its data processing functions.Often simply referred to as processor.
Main Memory: Stores data.
I/O: Moves data between the computer and its external environment.
System Interconnection: e.g. BUS for communication among CPU, main memory, and I/O.
The major structural components of a CPU are:
Control Unit (CU): Controls the operation of the CPU and hence the computer.
Arithmetic and Logic Unit (ALU): Performs computer’s data processing functions.
Register: Provides storage internal to the CPU.
CPU Interconnection: communication among the control unit, ALU, and register.
What is Processing : On a computer system, To gain an understanding of the speeds at which modern processors function, it should be noted that speed of the order of 10 instructions per second are quite common in modern processors. We shall also see that, as compared to main memory speeds, a processor today may be at least an order of magnitude faster.
Let's learn basic processing of Computer Processor :
Von Neumann Architecture:
The invention of stored program computers has been described to a mathematician, John von Neumann, who was a contemporary of Mauchley and Eckert.. Stored-program computers have become known as von Neumann Architecture.
Today’s stored-program computers have the following characteristics:
- I/O system
A single data path between the CPU and main memory.
The capacity to carry out sequential instruction processing.
This single path is known as the von Neumann bottleneck systems.
Thanx.. We will carry on and learn the basics of Von Neumann Architecture in next chapters..