Based Ypl2440 Embedded Video Monitoring System And,

This paper analyzes the embedded video monitoring system in the past,discovered the deficency of wired network ,the deficency of data which can not be saved in the card,and the deficency of transfer rate as the interface choosed by carema.The system choose YPL2440 board,introduce wireless network and carema based USB-interface,and SD card.Thus, On the basis of the original,to increase wireless card and carema based USB-interface,SD card and USB HUB disappear those deficencies.For embeded system, the choose of software and hard is successful base of the system,by the analysis of requirements for the system,and comparion of different devices existing the same function. In hardware, choose YPL2440 board based ARM,and carema and wireless card based USB.In software, choose linux as operation system of the system,JPEG as compressed algorithm, Ipv6 as transfer protocol,and boa as Web servers.Due to cross-compile environment is in order to compile the procedures in the development of on-board , So create a cross-compiler environment is a development on different board,come true the cross-compiler adapted to YPL2440;secondly, on the basis of bootloader completed,achieved the supportion for yaffs file system, the command of the operation of NAND flash storage device,and increasing some commands to show the version of U-BOOT and the size of NAND card; For the kernel cutting remove drivers system does not require, in this system, implemented in the kernel of the re-division of nand,which can come ture system startup files and applications to be placed separately, and to achieve static device nodes created by user dynamically created; Dynamically creates device nodes based on udev and comes with the root file system library files produced based on YPL2440 development board.Analysis schematic, diagram, bus topology of USB-HUB,come ture dirver of USB-HUB,finaly add the driver to the kernel to achieve the USB HUB Function.Over changes to the wireless network card driver,and add dynamical library and driver to kernel to achieve wireless card driver. Selected camera generic zc0301 driver,but has not media directory in some kernel of linux and configuration documentation of the dirver, through the establishment of media in this directory and related configuration files can be configured in the kernel directory tree shows camera driver。Here provide second methods of interface inadequate, On the basis of changes in the original hardware, driven to enable them to support USB HOST. Analysis the registers and structure used by SD memory cards, Finally, a device_driver structure to achieve the SD of the driver, the final adoption of the driver, added to the kernel, and test the SD driver.Through the use of the Boa server, TCP transport protocol, the java client-side code and server-side CGI code for video surveillance system to achieve the client display. Finally Ipv6 protocol to video transmission can be achieved in the system.