Design And Implementation Of Embedded-oriented Watchdog

With the development of society, people living in the community environment demands more and more intelligent. In order to achieve these requirements, the need in the community to set up a wireless sensor network, but in order to give full play to the role of wireless sensor networks, sensor networks must be collected information timely and accurate transmission to the outside world, on a comprehensive analysis of these data, processing, end - region to be monitored with accurate information; and can also be in wireless sensor networks for the various nodes to issue control commands, such as remote control operations. Wireless sensor network based on security issues to consider in this paper to improve the functional design of the Watchdog system, mainly for the application of the base station. This article comes from the actual project, with strong practicality.Embedded systems development in accordance with the general process, first of all, the design of the hardware architecture of the base station. Include: (1) as a base station ARM9 S3C2410 chip CPU; (2) used for the master chip CS8900A Ethernet controller module; (3) to make transparent to the wireless base station can connect to the Internet on the DTU module; (4) using CC2420 chip hardware platform as a base station of a wireless sensor network communication module.After perfecting the hardware in the base station, base station software programs to take into account the stability, we have introduced a Watchdog: posed by the single-chip micro-computer system, often as a result of the work of single-chip will be the interference from external electromagnetic fields , causing the procedure to run the fly to be trapped in the death cycle of the normal operation of the procedure was interrupted by the single-chip control system can not continue to work, would cause the entire system to a standstill state, the occurrence of unpredictable consequences, so out of single-chip real-time monitoring of running status of the consideration, it has created a specialized program for monitoring the status of single-chip chipset, that is, Watchdog, commonly known as the "watchdog."Watchdog know what is done, the next task is then to realize and apply it. Watchdog from the past, we found that Watchdog is a hardware or software Watchdog, there is the issue one way or another, and this article is to achieve the combination of hardware and software Watchdog, the shortcomings of the two complement each other out, together with the base station application, thus the realization of a hybrid system of Watchdog.