Study And Implement Of An Embedded System Based On USB Host

USB(Universal Serial Bus) came forth in 1995, and have become a standard solution in establishing the link between PC and peripheral equipments. Because of extremely extensive application of it, USB is attracted to apply in embedded system for expanding the system bus to link with the peripheral equipments.But in most applications, USB equipments are used in the slave (peripheral)mode, linked to the PC as the peripheral equipment. And it also need USB equipments to work in the host mode with the hand-in devices' development.So the scheme to realize the embedded system based on SL811HS, which can communicate with the flash disk is researched, and it has been applied to a digital camera system successfully.This kind of solution realize the application of USB host in embedded system without PC, and in digital camera application, it makes the camera to read and write the flash disk directly. So it enlarges the memory capacity and also improves the facility. The factory can lower its cost and the user can use the camera easily. In a way this solution also solves the problem that which kind of memory is chose to use.This thesis mostly expatiate the analyse of USB specific 1.1, the design of hardware and software of the USB Host Demo, the application in the digital camera. The details are discussed as below:(1) Analyse USB specific 1.1, parse the host part of USB and USB Mass Storage Class.(2) Parse the USB host controller SL811HS, design the USB Host Demo; Realize the enumeration, configuration of USB device, finish the USB Bulk in and Bulk out transfer which supports the Mass Storage class; Use the interrupt service program to convenient for applying in different system with different processors.(3) Design an application used in digital camera and the sample camera passed the test.