Difference Between USB 1.0 And USB 2.0
The Universal Serial Bus or USB has become the most used port in computers today. It currently exists in two versions. 1.0 which was the original standard of USB, and 2.0 which is the improved version for newer devices. To the end user, the difference between these two devices is purely in its speed. USB 1.0 devices can only achieve a maximum speed of 12Mbps while 2.0 devices can theoretically achieve up to 40 times that at 480Mbps. The real world speeds are lower for both standards since there are other factors that can affect its total throughput.
Originally intended for much slower devices, the initial USB implementation did not provide any option for high speed data transmission. Devices like mice, keyboards, game controllers, and a few others, which were the devices that USB was for, usually transmitted only a very small amount of data to function properly. But as USB became more popular, more devices also began to switch to USB because of the growing popularity of the USB port and the relative ease of plugging in devices. High speed devices like thumb drives proliferated quickly, and digital cameras and camcorders began to sport a USB cable for connecting to computers, but the hindrance of very slow connection speeds became quite apparent rather quickly.
The 12Mbps speed of 1.0 devices is already an upgrade to the very first standard which only allowed 1.5Mbps connections. USB 1.0 devices can either be a low speed device which runs at 1.5mbps or a full speed device at 12Mbps. A connecting device must identify whether it's a low or full speed device at its initialization. USB 2.0 adds the high speed connection to the previous two, and it is in high speed that you can get the 480Mbps theoretical throughput.
Because USB 1.0 can only recognize low speed and full speed devices, USB 2.0 must create a workaround in order to retain backwards compatibility with the older standard. A 2.0 device identifies itself as a full speed device at first then negotiates with the controller via a series of chirps. Once the controller identifies the device as a high speed device, the connection is then reset to and high speed signalling is used.
Summary:
1.USB 2.0 is the upgrade of 1.0
2.USB 2.0 is much faster compared to 1.0
3.USB 1.0 has two modes of operation while 2.0 adds another one
4.USB 2.0 devices needs to connect as a 1.0 device and negotiate for a 2.0 connection
No comments:
Post a Comment