Design Of Sulfur Dioxide Concentration Detector

As one of the most serious pollutants in atmosphere, sulfur dioxide has a tremendous impact on the ecological environment, building materials and human health. In many cities of china, sulfur dioxide concentration in the air have exceeded the national standards with the development of industry and increasing of pollution. Therefore, it is necessary to detect the concentration of sulfur dioxide in real-time besides of control it from source. However, most of the current air quality detections are introduced from Europe and the United States, although there is considerable demand in domestic. Therefore, the research of the sulfur dioxide concentration detector is imperative.A sulfur dioxide detector was designed using the method provided in the national standard GB3095-1996- Ultraviolet fluorescence method, which was also defined as the standard method of many other countries and the World Health Organization. The specific design includes tow parts-hardware and software. The hardware parts take LPC2138 produced by Philips as microcontrollers, and consist of single regulating module, A/D conversion module, keyboard input module, LCD display module, alarm module and RS232 serial communication interface to communicate with the host computer for data transmission and preservation. The software part has transplants the real-time operating system-μC/OS-Ⅱ. The program has been loaded, the storage space has been divided and command file has been prepared in the environment of ADS1.2.what more, programming has been finished for system initialization, interrupt sampling, real-time display of data, alarm and data communication, etc. In order to strengthen stability, anti-jamming and watchdog program were also designed.At last, the system debugging method was analyzed, and the graphs got from experiment are displayed. For later study, summary and outlook was carried out, several parts which need for improvement were given...