Computer Architecture and Organization - Introduction PDF

Chapter 1: Introduction Computer Architecture and Organization Department of Computer Engineering  Computer Architecture & Organization ❑ Computer architecture refers to those attributes of a system visible to a programmer or, ❑ Those attributes of a system that have a d...

Chapter 1: Introduction Computer Architecture and Organization Department of Computer Engineering  Computer Architecture & Organization ❑ Computer architecture refers to those attributes of a system visible to a programmer or, ❑ Those attributes of a system that have a direct impact on the logical execution of a program. ❑ Examples of architectural attributes include: ✓ The instruction set ✓ The number of bits used to represent various data types (e.g., numbers, characters) ✓ I/O mechanisms ,and ✓ Techniques for addressing memory Computer Architecture and Organization 2  Computer Architecture & Organization ❑ Computer organization refers to the operational units and their interconnections that realize the architectural specifications. ❑ Organizational attributes include those hardware details transparent to the programmer, such as ✓ Control signals ✓ Interfaces between the computer and peripherals, and ✓ The memory technology used Computer Architecture and Organization 3  Computer Architecture & Organization ❑In summary, computer architecture focuses on the conceptual design and structure of a computer system, While ❑Computer organization deals with the practical implementation details and physical realization of that design. ❑ Computer architecture defines what the computer should do, while ❑Computer organization determines how it will be done at the hardware level. Computer Architecture and Organization 4  Architecture & Organization ❑Computer architecture deals with the abstract, high-level structure and functionality of a computer system, while ❑Computer organization deals with the concrete, low-level implementation details required to realize that structure and functionality in physical hardware. ❑ Computer architecture sets the design goals and principles, while ❑ Computer organization implements those goals and principles in hardware. Computer Architecture and Organization 5  Structure & Function ❑ Structure: The way in which the components are interrelated ❑ Function: The operation of each individual component as part of the structure ❑ In terms of description, we have two choices: starting at the bottom and building up to a complete description, or ❑Beginning with a top view and decomposing the system into its subparts. ❑ Evidence from a number of fields suggests that the top down approach is the clearest and most effective Computer Architecture and Organization 6  Function Figure 1.1:Functional View of Computer System ❑ Figure 1.1: depicts that the basic function performed by Computer. ❑All computer functions are: Data processing Data storage Data movement Control Computer Architecture and Organization 7  Possible Computer Operations a) Data movement- simply transferring data from one peripheral or communications line to another Computer Architecture and Organization 8  Possible Computer Operations b) data storage device- with data transferred from the external environment to computer storage (read) and vice versa (write). Computer Architecture and Organization 9  Possible Computer Operations c) Data Processing from storage and stored the result back to storage Computer Architecture and Organization 10  Possible Computer Operations d) Processing from storage to I/O and vice versa Computer Architecture and Organization 11 ❑When data are received from or delivered to a device that is directly connected to the computer, the process is known as input–output (I/O), and ❑ The device is referred to as a peripheral. ❑When data are moved over longer distances, to or from a remote device, the process is known as data communications. ❑ Control unit manages the computer’s resources and orchestrates the performance of its functional parts in response to those instructions. Computer Architecture and Organization 12  Computer Top Level Structure Peripherals Computer Central Main Processing Memory Unit Computer Systems Interconnection Input Output Communication lines Computer Architecture and Organization 13  Four Main Structural Components of Computer ❑ 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 and programs temporarily ❑ I/O: Moves data between the computer and its external environment. ❑ System interconnection: Some mechanism that provides for communication among CPU, main memory, and I/O. ❑ A common example of system interconnection is by means of a system bus consisting of a number of conducting wires to which all the other components attach 14  Central Processing Unit (CPU) Structure CPU Computer Arithmetic Registers and I/O Login Unit System CPU Bus Internal CPU Memory Interconnection Control Unit Computer Architecture and Organization 15  Major Structural Components of CPU: ❑Control Unit: Controls the operation of the CPU and hence the computer ❑Arithmetic and Logic Unit (ALU): Performs the computer’s data processing functions ❑Registers: Provides storage internal to the CPU ❑CPU interconnection: Some mechanism that provides for communication among the control unit, ALU, and registers. 16  Control Unit Structure Control Unit CPU Sequencing ALU Logic Control Internal Unit Bus Control Unit Registers Registers and Decoders Control Memory Computer Architecture and Organization 17  Computer Evolution and Performance ❑ The evolution of computers has been characterized by: ✓ Increasing processor speed, ✓ Decreasing component size, ✓ Increasing memory size, and ✓ Increasing I/O capacity and speed. ❑ One factor responsible for the great increase in processor speed is the shrinking size of microprocessor components because, ❑ It reduces the distance between components and hence increases speed. ❑ However, the true gains in speed in recent years have come from the organization of the processor 18  Computer Evolution and Performance ❑A critical issue in computer system design is balancing the performance of the various elements ❑In particular, processor speed has increased more rapidly than memory access time. ❑ A variety of techniques is used to compensate for this mismatch, including caches, wider data paths from memory to processor, and more intelligent memory chips ❑ Read About Computer Evolution In detail in your text book 19  End Of Chapter 1 Computer Architecture and Organization Department of Computer Engineering