单片机小型粮库温湿度智能监控系统的设计与研究论文.doc

摘要 粮食储藏是国家为防备战争、荒灾以及其他突发性事件而采取的有效措施。粮食是人类生存的必需品，温度与湿度是保存好粮食的先决条件，随着中国加入WTO和粮食市场的逐渐开放，储存大量的粮食对稳定国民经济的发展起到至关重要的作用。单片机在这种系统中往往作为一个终端机，安装在系统的某些节点上，对现场进行实时的测量和控制。单片机的高可靠性和强抗干扰能力，使它可以置于恶劣环境的前端工作Abstract The food storage is the national guard against war, for Huang zai and other unexpected events and take effective measures. Food is the human survival necessities, temperature and humidity is to keep the good food prerequisites, with Chinas accession to the WTO and the opening up of the food market, store large amounts of food to stabilizing the development of national economy play a crucial role. Affect food security is the main parameters of grain storage humidity and temperature, between the two are interrelated. People often use thermometer, island-from mosquitoes to measure the temperature and humidity of warehouse, through the artificial heating, add wet, ventilation and cooling method to control the warehouse temperature, humidity, this method not only control precision low, real-time, and operation of the personnel labor intensity. At the same time temperature and relative humidity can lead to big large variation seed range decay or influence of seed germination rate, thus brings great economic and property losses. Therefore, ensure the warehouse of the appropriate temperature and humidity on agricultural seed storage quality guarantee is very important. This design is divided into the upper and lower levels structure, lower place machine system to ATMEL company produces the AT89C51 as humidity and temperature monitoring core components, the temperature sensor DS18B20, it USES single bus interface, can be measured directly read things value; Select HS1101 as humidity sensor, through the wet sensitive capacitance in 555 timer and resistors circuit, will the change of capacitance values to the inverse of a voltage and frequency signal, and USES the RS485 communication and the upper machine;Once the temperature or humidity value more than setting threshold, can realiz