Research And Implementation Of Applications Based On Usb2.0

With the development of PC peripherals and digital products, the interface and connection between them and PC has become a difficult problem. The USB Specification was proposed by Intel, Compaq, Microsoft and other companies in 1994, its emergence simplified the connection between PC and PC peripherals, and made PC interface extension to become more easier. It has more advantages than other bus, such as supporting of hot insert&plug, high transmission speed and low expense. Now, USB has been widely used in PC peripherals and it has become one of the best selections in many buses. Especially the 2.0 revision of the USB specification is issued, which is the landmark in the USB history. Its transmission speed is 480Mb/s. So it's possible to realize the high transmission speed between PC and the peripherals.This paper researched the basic principle of USB technology in detail, and introduced the basic frame of an application system based on USB 2.0 in detail. In consideration of the digital imaging and USB technology are hot techniques in recent years, we select a USB 2.0 image acquisition system to be example, and give the solution of that system. The paper generalized the developing background and the advantages of USB, the hierarchical structure including protocol, and transmission means of data etc briefly. Then the design and implementation of the hardware and software on both host and device sides of an image acquisition system based on USB 2.0 are demonstrated in detail. In hardware segment, after analyzing the features of USB interface chip CY7C68013 and CMOS image sensor OV7620, the paper proposes the layout of the circuit design, and the implementation of the main functional modules is introduced in detail. In this design, we select CMOS image sensor OV7620 to complete the image acquisition, and select USB interface chip CY7C68013 to complete the image transmission. In software segment, firmware design and device driver are introduced in detail.