A Design Of Embedded Storage System Based On ARM

With a wide range of embedded system applications and hardware technology, information collection and data management systems have become increasingly demanding. Many embedded products not only in itself a larger storage capacity, but also ask for removable storage devices for data cross-platform use. Because of this real demand, embedded memory systems are increasingly concerned.In this thesis, we used the development of a multi-parameter monitor as the project background, studied data storage and data exchange principle of ARM-based embedded systems in-depth, proposed a set of data management solutions supporting local and removable storage, and discussed the implementation process in detail.Based on the AT91SAM9261 platform, this thesis can be divided into two parts:local storage system based on NAND Flash and U disk storage system based on embedded USB host. Both of the two storage systems can exchange data directly.NAND Flash has gradually become commonly used in embedded systems as data storage devices because of its large capacity, low cost, small size etc. In this thesis, we studied a lot of data storage management solutions, and used NAND Flash storage medium as local storage. Besides, we mounted YAFFS2 File System which was specifically designed for high-capacity NAND Flash for data management. The YAFFS2 File System fully takes into account the structural properties of NAND Flash, including bad block management, read and write balanced, error checking, power-down protection and many other important functions.We can use U disk to store data in ARM-based embedded environment based on removable storage system, which was a good solution to the cross-platform data acquisition problems in embedded environment. The USB host port based on OpenHCI from AT91SAM9261 processor implements complex USB data transfer protocol using software programs completely. The transplantation of FAT file system makes the use of U disk data on most operating systems possible.