The document discusses USB (Universal Serial Bus). It provides details on the history and development of USB, including its features and versions. It describes USB cables, connectors, ports and their uses. It also discusses USB pen drives, their advantages for data transfer and storage, and the top five uses of pen drives including file transfer between devices, backup storage, and adding memory via ReadyBoost.

1. USBUSB
(UNIVERSAL SERIAL BUS)(UNIVERSAL SERIAL BUS)
Presented by : Shehrevar Davierwala
Contact : shehrevar@live.com

2. Contents
 What is USB?
 History of USB….
 Features of USB….
 USB cable.
 Features of USB cable.
 Version of USB.
 Terminology.
 USB system.
 Enumeration.
 Fundamental packets.
 Location of USB ports.
 What uses USB ports
 USB pen drives..
 Best five uses pen
drive.

3. What is USB?
 USB is know as Universal Serial Bus.
 It is used to transfer data from one
device to another.
 Basic architecture of USB is host-to-device
connection and transaction.

4. History of USB
 It was first invented by Iseraeli company called
‘M-system’ and the brand is called ‘Disk on key’.
 USB was released by no.of companies including
Compaq,DEC,Microsoft,Intel,
NEC,Nortal.
 Many companies claimed to have invent the usb
storage device but M-system was the one to get
the patent in 2000.

5. Features of usb

Attachment is detected and device is configured
automatically.
 Single standard connector.
 127 devices can be connected via hubs.
 Three device speeds:
 Low (1.5Mb/s)
 Full (12Mb/s)
 High (480Mb/s)
 Power: 5V, 100mA-500mA
 Error detection/recovery is automatic
 Low cost

6. USB cable…..
 D+ =Signal Line
 D-= Signal Line
 VBUS = Power
Supply5.25V to 4.2V
 VGND = Ground
 Signal Lines are twisted

7. Features of USB cable…
 The maximum cable length is five meters orapproximately 15 feet.
 The cables contain fourwires. Power, Ground, Data Plus (D+) and
Data Minus (D-). D+ and D- forma differential pair.
 The powerline is +5VDC.
 The usb connectors are of two types called A connectors
and Bconnectors.
 The A connectoris rectangularand the Bconnectorhas a
more rounded type mechanical structure.
 There are also mini A, mini B, and mini ABconnectors
which are smallerspecial versions of the A and B
connectors.

8. Types of connector
A connector
B connector

9. Versions of USB
 USB1.0 FDR: Released in November 1995.
 USB1.0: Released in January 1996.
 USB1.1: Released in September 1998.

10. Con….
 USB2.0: Released in April 2000. The
major feature of this standard was the
addition of high-speed mode. This is the
current revision.
 USB2.0: Revised in December 2002.

11. Terminology

12. USB system
 USB system consist
of three units
 1] USB host
 2] USB Cable
 3] USB DeviceHost Device
Cable

13. Enumeration
 When a device is attached, the OS
“enumerates” the device, identifies its driver,
and assigns an address to it.
 In the enumeration process, data
structures (transfer descriptors) contain
information needed by the host to generate
transactions. This information includes:

14. Con….
 USB device address.
 Type of transfer.
 Direction of transfer (write or read).
 Transfer size (# of bytes).
 Speed.
 Address of the device driver’s memory buffer

15. Fundamental packet
 The host controller initiates and manages all USB
transfers.
 A USB transfer consist of one or more transaction and
each transaction contains up to three packets.
 There are 3 types of packets
 1] Token 2] Data 3] Handshake
 Each packet contains packet ID block of information and
error checking codes.

16. PC USBPorts…where are
they?
 Front of PC…built in
 Backof PC…built in
 On Motherboard…unconnected
 On Motherboard…connected
 Add-On card installed
 PCMCIA Adapterinstalled
 A USB“Hub” installed

17. USB ports…. Front of PC…built
in

18. USBports…. Rear of PC…built
in

19. USBports….Already in
Motherboard….

20. USB ports….connected to
motherboard

21. USB ports…add on card
installed

22. USB ports…Laptop PCMCIA
Adapter
PCMCIA: Personal
Computer Memory
Card International
Association.
It is used to add
memory or credit
card size peripheral
devices.

23. USB ports…USB Hub
connected

24. USB ports…What can use
them?
 Printer, Scanner, Keyboard, Mouse
 Drives…Hard, Floppy, CD, Zip, Flash Drives
 Wireless…”Bluetooth”, Keyboard, Mouse
 Flash memory cards…Card Readers
 Hubs…up to 127 Ports useable
 Cameras…DigiCam, WebCam,
[no VideoCam]

25. USB Pen Drives (flash drive)
 USB flash drive was invented by Dov Moran.
 Ajay Bhatt of Intel was the co-inventor.
 Pen Drive is a latest invention in USB which
help us in many ways as it help to store your
precious data safely and to transfer it from one
place to another.

26. Pen Drives…….
32
GB
4
GB
2
GB
4
GB

27. Best Five uses of a pendrive
1 Transferring files from one PC to another.
This will of course be limited to the size of
the Pen drive, but with sizes higher than 32
GB now available. This is the first use
anyone will put a pen drive into.

28. Cont….
2 As a small backup solution. You can install
Windows XP or vista , to a USB pen drive.
So if for any reason you can’t boot to
Windows, you can still boot to an installation
of Windows, plug in an external hard drive
and take off any information from the hard
drive before formatting.

29. Cont………
3 As temporary RAMin Vista. In Windows Vista,
ready boost allows you to allocate a pen drive
as RAM. Microsoft has introduced a new
technology called ReadyBoost. With the help
of this technology one can use any Flash
drive, SD Cards as the third memory option for
the computer.

30. Cont……
 In order to activate the ReadyBoost technology on
your FlashDrive or Memory Cards, you have to
follow these steps…
1. Open My Computer.
2. Right Click on the Removable Disk Drive
and select Properties.
3. Click on Ready Boost Tab.
4. Enable the feature by selecting the option and
allocate the amount of space you want to use as
memory.

31. Cont………………….
 Things to be noted….
1. Regardless of the fact that you use Readyboost
or not, you need at least 512 Mb of memory to run
Windows Vista decently.
2. If your device is not giving the option of
ReadyBoost then it means that it doesn’t clear up
the minimum data trasfer rate required by Read
Boost technology.

32. Cont…….
 The benefits of Flash Drive or Pen drive as a
source of Memory :
1. It is faster than the virtual memory which is
accessed through the hard disk drive.
2. It is cheaper as compared to the actually
Physical Memory.

33. Cont…
4.Portable applications. You can carry
many portable applications on your Pen
drive. eg: Mozilla thunderbird.
5.Booting to LINUX
Installing a Linux distro to a pen drive
will allow for the use of the hard drive and
all the files on it.