Design And Implementation Of Environmental Monitor System For Literature Library Based On FreeModbus

With the increasing importance of human heritage and development of traditional culture,governments are making great efforts to protect the precious literature resources everywhere,in order that our future generations may know more about the traditional history and culture.libraries,archives and other literature centres,keep a lot of old books,classical books and precious archives and other literature resources with collection value,however,due to improper storage,the damage of literature resources become more and more serious.Especially in the southern region,the annual plum rain season will increase the humidity in the air.Air moisture is more likely to lead to the paper documents moth,accelerate paper aging and other problems.Therefore,it is particularly important to maintain,organize,moistureproof paper documents and archives.In view of the demand of the preservation environment of paper documents in archives,libraries and museums,a design scheme of environmental monitor for real-time monitoring of environmental parameters is presented.Firstly,this thesis analyzes the problem of literature damage caused by the improper preservation of precious documents at domestic and abroad,and makes us pay more attention to the preservation of paper documents through examples.And to search the domestic and foreign library documents storage standards,by storing standards to determine sensor types and the function of the system,the system includes requirement analysis and system design requirements.Secondly,the design of environment monitor and environment controller is introduced,both the environment monitor and controller adopt stmicro's STM32 series chip as MCU.The monitor is loaded with sensors for temperature and humidity,ozone,PM2.5,carbon monoxide,carbon dioxide,fire detectors and leak alarm controllers,and the parameters are displayed on the LED screen in real time.The controller collects the parameters collected by the monitor and compares them with the parameters threshold values set,if the parameters detected are not within the threshold range,the appropriate external device will be turned on,to restore the environment to a state suitable for document storage.Data is transmitted between the upper computer and the controller via wired RS-485,and environmental parameters are collected from the controller and stored in the database,the data is presented to the client in the form of the client.To ensure simultaneous multi-task,the system makes full use of the characteristics of the real-time operating system ?C/OS-?,in addition,FreeModbus communication protocol is transplanted to make it transmit the collected data stably.The communication mode between the monitor and controller adopts wired RS-485 communication and wireless ZigBee/LoRa communication,which makes the communication between the monitor and controller more stable.This design can collect real-time and accurate environmental parameters to provide a good environment for the preservation of paper materials in the venue.Finally,turn the system into a product,including the design of the product chassis,as well as the product field test situation,product test process and result analysis.After the long-term field test,the system can run stably,and there will be no abnormity for a long time,so as to meet the expected demand.