USB:
Universal Serial Bus.
Introduced:
In 1994, by Ajay Bhatt of Intel.
Team who joined in implementation of USB:
Compaq, IBM, DEC, Intel, Microsoft, NEC and Nortel.
Purpose:
Data transfer rate of 12 Mbps.
Major operating system.
Provide storage.
Data transfer rate:
Speed that data is transmitted from one device to other.
Measured in:
Mega bits (Million bits) or Mega bytes (Million bytes).
Data transfer speeds:
USB 1.1 - 12 Mbps.
USB 2.0 - 480 Mbps.
USB 3.0 - 4,800 Mbps.
Firewire - 400 Mbps or 800 Mbps.
(e) SATA 2.0 / 3.0 - 3 Gbps / 6 Gbps.
Before invention of USB'S how they connect to computers:
Serial and parallel ports to plug devices in to computers and transfers data.
Serial port:
Connector by which device that sends data one bit at a time.
Parallel port:
Transmit or receive data down multiple bundled cables such as printer.
USB drive also known as:
USB flash drive (or) key chain drive.
USB uses:
To connect computer to devices such as printers, scanners, digital cameras.
Importance of USB drive:
Multipurpose tool.
Keep data safe and secure.
Backing up data.
Versions of USB:
| Release Name | Release Date | Maximum Transfer Rate |
|---|---|---|
| USB 0.8 | December 1994 | - |
| USB 0.9 | April 1995 | - |
| USB 0.99 | August 1995 | - |
| USB 1.0 | November 1995 | - |
| USB 1.0 | January 1996 | Low speed (1.5 Mbits/sec) |
| USB 1.1 | August 1998 | Full speed (12 Mbits/sec) |
| USB 2.0 | April 2000 | High speed (480 Mbits/sec) |
| USB 3.0 | November 2008 | Super speed (5 Gbits/sec) |
| USB 3.1 | July 2013 | Super speed+(10 Gbits/sec) |
What version of USB have installed in your computer:
USB port name contains "Universal Host" port version 1.1
Both "Universal Host" and "Enhanced Host" port version is 2.0
"USB 3.0" port version 3.0
USB color coding:
Black or white : Type-A or Type-B
Blue : Type-A or Type-B super speed
Teal blue : Type-A or Type-B,super speed+
Yellow, orange, Red : Ports only. High current or sleep and charge.
Types of USB connectors:
Type - A:
One end peripherals like mice, keyboard, personal computers, power adapters.
Square connector mostly used for printers.
Mini USB:
Smaller than regular USB.
Before micro USB came mini USB used in mobile devices.
Still using in cameras.
Micro USB:
Mobile and portable devices.
Type - C:
High transfer rates and more power than previous USB rates.Laptops, phones, tablets.
4 wires.
What each wire in the USB cable means:
Red indicates positive wire with 5 volts of DC power.
Green is the data as a "negative" wire.
White is the data as a "positive" wire.
Black has always been the ground wire in electronic devices.
Which wire has power in USB cable:
Red wire with 5 volts.
How USB works inside cable:
 |
| USB cable |
 |
| Strip one end of USB cable |
 |
| Connect negative wire of your light to ground wire of USB positive wire of light to red wire of USB |
 |
| Connect USB cable to port light will be shine |
Easy to use.
Low cost.
Low power consumption.
Convenient.
Large amount of information can be stored.
Disadvantages:
Small size and easily lost.
Can be damaged.
No security.
Applications:
Touch pads.
Modems.
Cameras.