The next version well talk about is usb 20 usb 20 was

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The next version we'll talk about is USB 2.0. USB 2.0 was released in mid-2000 and offered a substantial increase in speed. In fact, it's often referred to as high speed USB. USB 2.0 is still used quite a bit today. Most USB ports in computer are USB 2.0 ports. USB 2.0 has a maximum data rate of 480 megabits per second. This transfer rate is much faster than USB 1.1 and actually helped USB gain popularity as a connection interface for external storage devices. USB 2.0 is backwards compatible with USB 1.1 devices. However, USB 1.1 devices are still limited to the 12 megabits per second data rate. One important thing to know about a USB version is that it's not just the ports and devices that have version associated with them. The USB cables used to connect devices also have a version association. This means that if you connect a USB 2.0 device using a USB 1.1 cable, you will be limited to the slower data rate of USB 1.1. Because of this, always make sure you are using the appropriate hardware when connecting devices. Next, we'll talk about USB 3.0. USB 3.0 was released in late 2008, and it's sometimes referred to as super speed USB. USB 3.0 offers a huge speed increase over previous versions. It has a maximum data rate of five gigabits per second. USB 3.0 cables, devices, and ports can be easily identified by their blue connectors, and just like previous versions, USB 3.0 is backwards compatible. The last USB version we'll talk about is an enhancement to USB 3.0 and is referred to as USB 3.1. USB 3.1 offers data rates of up to 10 gigabits per second. One thing to keep in mind about these transfer speeds is that the bandwidth is shared among all devices connected to the same USB bus. This means that the more devices you connect to a bus, the slower each device will operate. With only four or five devices connected, you probably won't see any performance issues. However, if you start connecting a lot of devices, you will most likely notice slower speeds. The main thing to know is that the more USB devices you connect to a single bus, the slower overall speed you are going to have. Hot Plugging 5:53-6:15 In addition to the different versions, USB has a couple of cool features that you should know about. The first is the ability to connect and disconnect devices while the computer or device is powered on.This functionality is known as hot-plugging. For example, if you needed to connect an external storage device, you could simply plug it in to an open USB port without needing to shut down the computer. Self-Powered and Bus-Powered USB Devices 6:16-6:51
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The second feature you should be aware of is USB's ability to provide power over the connection.USB devices can receive up to 500 milliamps of power from a USB 2.0 port and up to 900 milliamps of power from a USB 3.0 port. If this amount of power is sufficient for a device, it's considered a bus-powered device. This means the USB port provides 100% of its power.
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