february 10 th 2010 dehmani feth-allah m2 istre oral presentation universal serial bus
TRANSCRIPT
February 10th 2010
Dehmani Feth-Allah
M2 ISTRe
Oral Presentation
Universal Serial Bus
II. How does it work ?
Summary
I. Presentation (Where, When, Why…)
III. ApplicationsHOW
DOES IT WORK ?
APPLICATIONS
USBPRESENTATION
February 10th 2010
Presentation
HOWDOES IT WORK ?
APPLICATIONS
USBPRESENTATION
February 10th 2010
Purpose : Standardization of serial communication between a host and a device with a unique connexion and a unique communication protocol
Invented in 1996 by Microsoft, IBM, Intel, Compaq, Digital, NEC et Northern Telecom (USB 1.0)
Before invention of USB : Differents connexion port and protocol communication like RS-232, parallel, PS-2 or SCSI.
Generalities:
Presentation
HOWDOES IT WORK ?
APPLICATIONS
USBPRESENTATION
February 10th 2010
HOSTDEVICE
Hardware connexions :
February 10th 2010
4. GND1. VDD 2 & 3. DATA
(D+ & D-)
Signal connexions :
How does it work ?
HOWDOES IT WORK ?
APPLICATIONS
USBPRESENTATION
How does it work ?
HOWDOES IT WORK ?
APPLICATIONS
USBPRESENTATION
February 10th 2010
NRZI diferential encryption between D+ and D-
LSB first transmit (Little Endian).
Speed
USB release 1.0 1.1 2.0 3.0
Year 1996 1998 2000 2010
Speed 1,5 Mbit/sLow Speed
12 Mbit/sFull Speed
480 Mbit/sHigh Speed
4,8 Gbit/sSuper Speed
USB Bus description
How does it work ?
HOWDOES IT WORK ?
APPLICATIONS
USBPRESENTATION
February 10th 2010
« Host – Slave » system
Frame transmission (Token et Data)
8 bits 8 bits 7 bits 4 bits 5 bits
SYNC PID ADDRESS ENDP CRC
8 bits 8 bits 0 to 512 bits 16 bits
SYNC PID PAYLOAD CRC
Token frame
DATA frame
Communication protocol :
How does it work ?
HOWDOES IT WORK ?
APPLICATIONS
USBPRESENTATION
February 10th 2010
Control : for command operation (enumeration, state of the device…)
Interrupt : for device with garanted time delay (mouse, keyboard…)
Isochrone : for device with garanted bit rate (garanted bandwidth : ex : printer, camera…)
Bulk : for big data transmissions (take maximum bandwidth as possible)
Transmission :
How does it work ?
HOWDOES IT WORK ?
APPLICATIONS
USBPRESENTATION
February 10th 2010
Identification process of the device by the host
SPEED DETECTION
DEVICE IDENTIFICATION
Send descriptors
CONNEXION
High level in D+ ou D-
Enumeration:
Applications
HOWDOES IT WORK ?
APPLICATIONS
USBPRESENTATION
February 10th 2010
REAL TIME APPLICATIONS
DATA TRANSFER
OR CONTROL COMMAND
USB
BUS ENERGY
(only hardware, 500mA max)
Conclusion
February 10th 2010
Today, USB is one of the most serial protocole used
FireWire (Apple) is the alternative of USB (3 200 Mbits/s)
To sell USB device, you need to buy a Vendor ID (≈ 2000 $ US / year)
Thank You…