COA Chapter computer organization and architecture course for engineering1.ppt
- 1. Computer Organization and Architecture Chapter 1 Introduction To Computer System 1
- 2. Introduction • A computer can be viewed as a structure of components and its functions described in terms of collective function of its cooperating components. • Structure : is the way in which components relate to each other • Function: is the operation of individual components as part of the structure 2
- 3. 3 • Why Study computer Organization and Architecture? – Design better programs, including system software such as compilers, operating systems, and device drivers. – Optimize program behavior. – Evaluate (benchmark) computer system performance. – Understand time, space, and price tradeoffs. • Computer Organization – Encompasses all physical aspects of computer systems. – E.g., circuit design, control signals, memory types. – How does a computer work? • Computer Architecture – Logical aspects of system implementation as seen by the programmer. – Architecture is those attributes visible to the programmer – E.g., instruction sets, instruction formats, data types, addressing modes. – How do I design a computer?
- 4. Memory CPU Systems bus I/O Computer Central Processing Unit(CPU) Main Memory The Input/output (I/O) System Bus Computer Structure Main Structural Components 4
- 5. 5 Computer Components • At the most basic level, a computer is a device consisting of three pieces: • A processor to interpret and execute programs • A memory to store both data and programs • A mechanism for transferring data to and from the outside world.
- 6. Computer Function • In general term, the computer functions are: Data processing Data storage Data movement Control 6
- 7. What is computer Architecture ? Computer Architecture : • Concerns the structure and behaviour of the computer. • Refers to those attributes of a system visible to a programmer. • Those attributes that have direct impact on the logical execution of a program. • It refers to how do I design a computer? Examples – Instruction set, number of bits used for data representation, I/O mechanisms, addressing techniques. – e.g. Is there a multiply instruction? 7
- 8. Architecture • Architecture is those attributes 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 – Control signals, interfaces, memory technology. – e.g. Is there a hardware multiply unit or is it done by repeated addition? 8
- 9. What is computer Organization ? • It refers to the operational units and their interconnections that realize the architectural specifications. • The hardware details transparent to the programmer. • The physical aspects of computer system. • It refers to how features are implemented/organized together. • Examples: Control signals, interfaces, memory technology. 9
- 10. The von Neumann Machine The standard for present day computers. Use the Stored Program concept. Based on the published von Neumann Architecture by john von neuman (1903-1957). The Characteristics of von Neumann Machine • A Main memory system which stores both data and instructions. • ALU operating on binary data • A CPU with Control unit which interprets the instructions in memory and causing them to be executed • Input and output system. Input unit provides instruction and data to the system while output unit display results. 10
- 11. Structure of von Neumann Machine 11
- 13. • The Figure below depicts the four possible types of computer operations. • The computer can function as a data movement device (Figure a), simply transferring data from one peripheral or communications line to another. • It can also function as a data storage device (Figure b), with data transferred from the external environment to computer storage (read) and vice versa (write). • The final two diagrams show operations involving data processing, on data either in storage (Figure c) or en route between storage and the external environment (Figure d). 13
- 14. Operations (a) Data movement 14
- 16. Operation (c) Processing from/to storage 16
- 17. Operation (d) Processing from storage to I/O 17
- 18. Structure - Top Level Computer Main Memory Input Output Systems Interconnection Peripherals Communication lines Central Processing Unit Computer 18
- 19. Structure - The CPU Computer Arithmetic and Login Unit Control Unit Internal CPU Interconnection Registers CPU I/O Memory System Bus CPU 19
- 20. Structure - The Control Unit CPU Control Memory Control Unit Registers and Decoders Sequencing Login Control Unit ALU Registers Internal Bus Control Unit 20
- 21. Components • The Control Unit and the Arithmetic and Logic Unit constitute the Central Processing Unit • Data and instructions need to get into the system and results out –Input/output • Temporary storage of code and results is needed –Main memory 21
- 22. Computer Components: Top Level View 22
- 23. Connecting • All the units must be connected • Different type of connection for different type of unit – Memory – Input/Output – CPU 23
- 25. Memory Connection • Receives and sends data • Receives addresses (of locations) • Receives control signals –Read –Write –Timing 25
- 26. Input/Output Connection(1) • Similar to memory from computer’s viewpoint • Output – Receive data from computer – Send data to peripheral • Input – Receive data from peripheral – Send data to computer 26
- 27. Input/Output Connection(2) • Receive control signals from computer • Send control signals to peripherals – e.g. spin disk • Receive addresses from computer – e.g. port number to identify peripheral • Send interrupt signals (control) 27
- 28. CPU Connection • Reads instruction and data • Writes out data (after processing) • Sends control signals to other units • Receives (& acts on) interrupts 28
- 29. Buses • There are a number of possible interconnection systems • Single and multiple BUS structures are most common • e.g. Control/Address/Data bus (PC) 29
- 30. What is a Bus? • A communication pathway connecting two or more devices • Usually broadcast • Often grouped – A number of channels in one bus – e.g. 32 bit data bus is 32 separate single bit channels • Power lines may not be shown 30
- 31. Data Bus • Carries data – Remember that there is no difference between “data” and “instruction” at this level • Width is a key determinant of performance – 8, 16, 32, 64 bit 31
- 32. Address bus • Identify the source or destination of data • e.g. CPU needs to read an instruction (data) from a given location in memory • Bus width determines maximum memory capacity of system – e.g. 8080 has 16 bit address bus giving 64k address space 32
- 33. Control Bus • Control and timing information – Memory read/write signal – Interrupt request – Clock signals 33
- 35. Big and Yellow? • What do buses look like? – Parallel lines on circuit boards – Ribbon cables – Strip connectors on mother boards • e.g. PCI – Sets of wires 35
- 36. Physical Realization of Bus Architecture 36
- 37. Traditional (ISA) (with cache) 37
- 39. Bus Types • Dedicated – Separate data & address lines • Multiplexed – Shared lines – Address valid or data valid control line – Advantage - fewer lines – Disadvantages • More complex control • Ultimate performance 39