Software Design Of Area Monitoring System Based On ARM9 And Embedded Linux

In the context of rapid development and application of embedded and communication technology, image sensor and network technology have greatly promoted area monitoring system's development. The thesis designed a cost-effective area monitoring system which will apply in residential districts and other public places and extend other function according to user needs.The system composed of monitor/transmission module with high-performance S3C2440 processor, OV9650 camera chip and other chips, utilizes area's local network to transport data and displays image by host computer of monitoring center. The thesis mainly accomplished software design of monitor/transmission module.First of all, the thesis has completed the system transplanting of S3C2440 processor on the based of ARM920T. It mainly includes the transplanting of U-Boot-1.1.6, which enables the system to boot and to lead the Linux kernel normally; Cuts out and transplants the Linux-2.6.22 operating system kernel, which enables the performance of the processor to display fully, and simplifies the software development. Secondly, the memory management of ARM920T and embedded Linux are more complex and commonly used the the default memory management methods of boot-loader and operating system kernel to develop, the advantage is to shorten the product development cycle, the disadvantage is to limit the system performance. This thesis presents default memory access method, enforce the use of FCSE (Fast Context Switch Extension) method, locks cache method, and strictly abide by the underlying Linux management method. Proved by experiments, the system's performance and efficiency have approximately increased by 10%. Driver is the interface that the kernel of embedded operating system controls the various parts of the hardware. The upper application and system calls will eventually be achieved through the driver at the bottom. This thesis has carried out the design of K9F1208 NAND Flash driver, and has produced a root file system on its basis; carried out the design of K4S561632 SDRAM initialization procedure; carried out the design of OV9650 camera chip driver; carried out the transplanting of DM9000 network adapter driver, and completed the design of network procedural on its basis.At last, this thesis used the file management, the process control, the named pipe, the sharing memory, the semaphore and the signal to consummate the design of upper software, which enabled the system to realize to collect the real-time pictorial information of each important place in the area, and carried on the network transmission by a higher speed, finally completed the display of the upper computer on the monitoring center.