Design Of Embedded Environment Data Acquisition System Based On S3C2440 And GPRS

With the the rapid growth of Chinese economy and the improvement of industrialization, a large quantities of coal and oil and other mineral resources have been consumed,as a result,massive pollutants are discharged to the air;at the same time,with the improvement of people’s living level,automobile industry are booming,vehicle exhaust has also become one of the important sources of air pollution.In recent years,our country continues to erupt haze weather,haze contains sulfar,nitrides and various toxic particles,when these are inhaled in body,can lead to a variety of respiration system diseases.The haze has seriously affected the health of mankind.The haze is the result that a certain degree particles,temperature,humidity,air pressure and other meteorological conditions interact to each other,therefore,mastering the meteorological data and the particles’ situation has important guiding significance in haze treatment and prevention,air quality information report and prediction.Due to the complexity,variability and locality of the meteorological environment,it is necessary to carry out a long time,dynamic and multi-point detection.For the detection,we can directly measured in the field or in remote field;the former waste human resources and the efficiency is low; on the contrary,the latter are time saving,convenient and efficient.For the above application,with the combination of embeded technology and wireless communication technology,embeded environmental data acquisition system is designed under the framework of client and server.The client takes the S3C2440 processor as the core,and is transplanted the Linux operating system.SHT20 temperature and humidity sensor,BMP180 barometer,PMS3003 dust sensor and GPS module are equiped.The terminal collectes temperature,humidity,air pressure,dust content and geographical and transfers them to the server via GPRS(General Packet Radio Service) network,at the same time,in order to directly feel the image information,USB Camera is used to capture and upload the image to the server. The server is a multi-thread concurrent server based on TCP protocol,which can serve multiple clients,and can realize the remote observation of environmental data at the server side.The article describes the development process of the system in detail: Firstly,it introduces the system architecture and each sensing module,and than it tells about the configuration of PPP protocol stack and ppp daemon’s transplant of GPRS module;secondly, According to the sensor interface,it shows I2 C bus driver’s configuration and the designs of I2 C device driver, explains the design of drivers of character type equipment and the steps of compile them into system kernal in detail, and also gives the configuration of UART and camera application programming based on v4l2.in addition,it tells the realization of data network transmission and reception under TCP,the socket programming of client/server,and the construction of multi-thread concurrent server.finally,test the function of the system and make a summary.