BUS SYSTEM

1. BUS SYSTEM Members: Bui Thi Diep Nguyen Thi Ngoc Mai Vu Thi Thuy Class: 1c06

2. OVERVIEW 1 Setting the problem 2 Introduction of bus lines Introduction of typical buses 3 Conclusion 4

3. Setting the problems • How to connect components in the processor such as hard disks, memory, sound system, video system and so on? • How many parts are there in the modern bus system? • What should we know the bus? • How many kinds of bus? • What are some typical buses?

4. Buses in a computer system

5. Bus system BUS SYSTEM System Bus I/O Bus

6. System bus SYSTEM BUS FrontsideBus Backside Bus

7. I/O Bus ISA Bus (1981) PCI Express Bus (2004) I/O Bus AT Bus (1987) USB Bus (2000) AGP Bus (1996) PCI Bus (1993)

8. Understanding bus • Concept of bus system • Purpose of using bus • Characteristics of bus • Advantages of bus • Disadvantages of bus

9. Concept of bus • A bus in the computing is the set of physical connection(cable, printed circuits, ...) which can be share by multiple hardware components in order to communicate with one another.

10. Concept of bus

11. Purpose of using bus • The purpose of using bus is to reduce the number of “pathways” needed for communication between the components, by carry out all communication over a single data channel.

12. Characteristics of Bus • The amount of information that can be transmitted at once. • This amount, expressed in bit, corresponds to the number of physical lines over which data is sent simultaneously. • The bus speed is also defined by its frequency (expressed in Hertz), the number of data packets sent or received per second.

13. Bus disadvantages • The major disadvantage of a bus is that it creates a communications bottleneck. • A bus limits the maximum I/O throughput. • For high performance systems, designing a bus system capable of meeting the demands of the processor is a major challenge.

14. Bus Advantages • Two major advantages of a bus organization are: • Low cost: a single set of wires is shared between multiple cores • Versatility: new cores can be added easily and cores can be reused in a different design if the bus interface is the same

15. Bus Classification • 3 ways to classify kinds of bus: • Base on signal function: • Address bus • Data bus • Control bus • Base on speed: • VXL bus • Processor bus • I/O bus • Base on operation rules • Synchronous bus • Asynchronous bus

16. Mention Content • Address bus • Data bus • Control bus

17. ADDRESS BUS • Computer bus (a series of lines connecting two or more devices) used to specify a physical address • Consists of all the signals necessary to define any of the possible memory address locations within the computer, or for modular memories any of the possible memory address locations within a module • Defined as a label, symbol, or other set of characters used to designate a location or register where information is stored

18. ADDRESS BUS (cont) • An address must be transmitted to memory over the address bus before data or instructions can be written into or read from memory by the CPU or I/O sections • The width of the address bus determines the amount of memory a system can address • Example: • a system with a 32-bit address address 232 (4,294,967,296) memory locations.

19. ADDRESS BUS (cont) • Table 12: 80x86 Family Address Bus Sizes

20. DATA BUS • Function: the bidirectional data bus, sometimes called the memory bus, handles the transfer of all data and instructions  between  functional  areas  of  the  computer • Only  transmit  in  one direction at a time

21. DATA BUS • Transfer instructions from memory to the CPU for execution. It carries data (operands) to and from the CPU and memory as required by instruction  translation

22. CONTROL BUS • Used by the CPU to direct and monitor the actions of the other functional areas of the computer • Used to transmit a variety of individual signals (read, write, interrupt, acknowledge …) necessary to control and co-ordinate the operations of the computer

23. Typical buses – ISA Bus • Some focused information: • ISA = Industry Standard Architecture • ISA was a computer bus standards for IBM compatible computers.

24. Typical buses – ISA Bus • Some focused information: • The ISA bus was developed by a team lead by Mark Dean at IBM as part of the IBM PC project in 1981. • ISA bus is the oldest, slowest and soon to become obsolete I/O bus system.

25. Typical buses – ISA Bus • Some focused information: • Is used with sound cards, disk drives or most network and video cards. 16-bit ISA card 8-bit ISA (XT) card

26. Typical buses – ISA Bus • History: • In 1981, it appeared on the first PC the 8-bit ISA bus ran at a modest 4.77 – the same speed as the processor. • In 1982, it was extended for the XT (X-Tended Technology) system architecture. • In 1984, the newer 16-bit standard, the IBM AT bus, was introduced.

27. Typical buses – ISA Bus • History: • In1988, ISA was improved to 32-bit EISA (Extended Industry Standard Architecture) standard and renamed the AT bus. • In 1990s, most ISA cards remained as 8-bit technology. • Now, in late 2008, the extinction of vestigial ISA from chipsets may be on the horizon

28. Typical buses – ISA Bus • Comparison: 16-bit ISA Bus 8-bit ISA Bus

29. Typical buses – PCI Express Bus • Some focused information: • PCI Express = Peripheral Component Interconnect Express = PCI-E • PCI-E bus is an interconnect bus that allows you to add expansion boards to a computer. • PCI Express bus was developed in July 2002 • It is the development of PCI -> it’s compatible with PCI architecture

30. Typical buses – PCI Express Bus

31. Typical buses – PCI Express Bus

32. Typical buses – PCI Express Bus

33. Typical buses – PCI Express Bus • Advantages of PCI Express • High bandwidth, can reach up to 5-80 gigabits per second. • The serial technology offers a scalable performance. • Point-to-point link for each device. • Small connectors facilitate the implementation for system designers.

34. Typical buses – PCI Express Bus • PCI Express slots

35. Typical buses – PCI Express Bus • PCI Express slots (x4,x16,x1,x16) and PCI slot

36. Typical buses – USB Bus • Some focused information: • USB = Universal Serial Bus • It based on serial type architecture • It is an input-output interface • It quicker than standard serial ports

37. Typical buses – USB Bus • USB standards: • The USB 1.0 standard developed from 1995 • The USB 1.1 standards provide several clarification but doesn’t change speed. • The USB 2.0 standard obtains speeds reach 480Mbit/s • The USB 3.0 standard released in 2007, the speed is 4.8 GB/s.

38. Typical buses – USB Bus • Type of connectors: 2 • Type A: the shape is rectangular and used for less bandwidth intensive devices (keyboard, mouse, webcam, etc.) • Type B: the shape is square and used for high speed devices (external hard disks, etc.)

39. Typical buses – USB Bus • USB hub example

40. Conclusion • Bus is very importance in computer architecture • It’s used largely and in most of everything which is related to physical computers • Use Bus to connect components in a processor. • There are 2 main parts in the bus system: system bus and I/O bus.

41. Conclusion • We introduced some basic information about bus consists of concept, purposes of using, characteristics, advantages and disadvantages. • In the range of our research, we only mention some kinds of buses. They are address bus, data bus and control bus. • Some typical buses: ISA bus, PCI bus and USB bus.

42. Thank You !