Computer ArchitectureComputer Architecture

“The design of a computer system. It sets the standard for all devices that connect to it and all the software that runs on it. It is based on the type of programs that will run (business, scientific) and the number of programs that run concurrently” -- PC Magazine

“The design of the integrated system which provides a useful tool to the programmer”-- Baer

“The study of the structure, behavior and design of computers” -- Hayes

“The interface between the hardware and the lowest level software” --Hennessy and Patterson

What is Computer Architecture?

“Computer architecture is concerned with the structure and behavior of the computer as seen by the user. It includes the instruction formats, the instruction set, and techniques for addressing memory” – Mano

“The architectural design of a computer system is concerned with the specifications of the various functional modules, such as processors and memories, and structuring them together into a computer system”--- Mano

Computer Architecture?

1. Global system structure (Black box approach)ProcessorsControl modulesMemory modulesInterconnection structure

2. Processor level (Detailed individual component specification)InterfacesInstruction setsData Representation

Levels of Computer Description

3. Register levelSpecify internal operation of processor-level components at the word levelPrimitives:

RegistersCountersMemoriesALUsClocksCombinational logic

4. Gate levelSpecify operations at the individual bit levelGates are primitive elementsVery cumbersome to do manually (logic minimization, etc.)

Levels of Computer Description