William Stallings Computer Organization and Architecture 6 th Edition Chapter 1 Introduction

Architecture & Organization 1 Architecture is those attributes of a system visible to the programmer —Instruction set, number of bits used for data representation, I/O mechanisms, addressing techniques. —e.g. Is there a multiply instruction? Organization is how features are implemented —Refers to the operational units and their interconnections that realize the architectural specification. —Control signals, interfaces, memory technology. —e.g. Is there a hardware multiply unit or is it done by repeated addition?

Architecture & Organization 2 Many computer manufacturers offer a family of computer models, all with the same architecture but with differences in organization. —All Intel x86 family share the same basic architecture —The IBM System/370 family share the same basic architecture This gives code compatibility Organization differs between different versions

Structure & Function A hierarchical system is a set of interrelated subsystems. —At each level, the system consists of a set of components and their interrelationship. —The behaviour at each level depends only on a simplified abstracted characterization of the system at the next lower level. At each, the designer is concerned with —Structure is the way in which components relate to each other —Function is the operation of individual components as part of the structure

Structure & Function Two descriptions: —Bottom-up –Starting at the bottom and building up to a complete description. —Top-down –Beginning with a top view and decomposing the system into its subparts. –The clearest and most effective.

Function All computer functions are: —Data processing —Data storage —Data movement —Control Functional view of a computer

Operations (1) Data movement Data movement —e.g. keyboard to screen

Operations (2) Storage Storage —Even if processing data on the fly —e.g. Internet download to disk

Operation (3) Processing from/to storage Processing from/to storage —e.g. updating bank statement

Operation (4) Processing from storage to I/O Processing from storage to I/O —e.g. printing a bank statement

The Structure of Computer The computer interacts in some fashion with its external environment. —Peripherals —Communication lines Computer Storage Processing Peripherals Communication lines

Structure - Top Level Computer Main Memory Input Output Systems Interconnection Peripherals Communication lines Central Processing Unit Computer

Structure - The CPU Computer Arithmetic and Login Unit Control Unit Internal CPU Interconnection Registers CPU I/O Memory System Bus CPU

Structure - The Control Unit CPU Control Memory Control Unit Registers and Decoders Sequencing Login Control Unit ALU Registers Internal Bus Control Unit

Outline of the Book (1) Computer Evolution and Performance Computer Interconnection Structures Internal Memory External Memory Input/Output Operating Systems Support Computer Arithmetic Instruction Sets

Outline of the Book (2) CPU Structure and Function Reduced Instruction Set Computers Superscalar Processors Control Unit Operation Microprogrammed Control Multiprocessors and Vector Processing Digital Logic (Appendix)

Internet Resources - Web site for book —links to sites of interest —links to sites for courses that use the book —errata list for book —information on other books by W. Stallings —Math —How-to —Research resources —Misc

Internet Resources - Web sites to look for WWW Computer Architecture Home Page CPU Info Center ACM Special Interest Group on Computer Architecture IEEE Technical Committee on Computer Architecture Intel Technology Journal Manufacturer’s sites —Intel, IBM, etc.

Internet Resources - Usenet News Groups comp.arch comp.arch.arithmetic comp.arch.storage comp.parallel