| The mobile equipments in the cars are used widely along with the development of cars in the recent years. With the development of mobile devices, people ask for mass storage devices to store millions of data. Such as a great deal of data documents, pictures and the big capacity of video files, many memory cards can not satisfy the consumer, DVD Disc can resolve the problem very well.The topic of the research is to implement the function of transferring data by the interface of DVD, which based on the frame of XScale in embedded system. The research is using Intel XScale PXA255 processor and the operating system of Windows CE.NET 4.2.At first, the organization of DVD data and the file system of DVD disc is introduced. And then the structure of DVD interface, the command of interface and the ATAPI protocol is introduced, the differences between the ATAPI protocol and ATA protocol are discussed. At the hardware aspect, there is no appropriative interface in the PXA255 processor, and the research use the CPLD to carry out transporting data by PIO and DMA. The address signals and data signals of interface can be provided by the processor, and the control signals need the CPLD. At the software aspect, the driver is based on the memory structure of Windows CE and ATAPI transport mechanism. The initialization of the DVD driver, getting the information about the driver, and transferring data from the driver to the host by PIO and DMA is implemented. After that, it used CETK to improve the driver. And now, the capacity of block driver is stable. The rate of transfer data is more than two million bytes per second, and can satisfy the request after testing the driver. At last, the article summarizes the whole research, and then gives expectation to the following works. |
