基于DS18B20的啤酒發(fā)酵溫度測控系統畢業(yè)設計外文資料翻譯

1、 畢業(yè)設計外文資料翻譯題 目 基于ds18b20的啤酒發(fā)酵 溫度測控系統 學 院 自動化與電氣工程學院 專 業(yè) 自動化 班 級 自動化xxxx班 學 生 xxxxxxxxx 學 號 20100321166 指導教師 xxxxx 二一四年三月三十一日- 12 -advanced materials research vols. 108-111 (2010) pp 898-902 (2010) trans tech publications, switzerlanddoi:10.4028/temperature detecting system of beer fermentationbased

2、on ds18b20fen-ping zhou, hong-tao ma, bing-dong sui，and jia-mo suncollege of information science & engineering, hebei university of science and technologyhebei, shijiazhuang 050054, chinazhoufenping,mahongtaosuibd,sunjiamokeywords: ds18b20, temperature detecting, beer fermentation, bus-driving, faul

3、t detecting abstract. this paper introduces a temperature detection system in beer fermentation. a temperature monitoring system with characteristics of bus topology structure is composed of industrial computer, temperature detector, bus converter, transmission bus and especially 1-wire digital temp

4、erature sensor ds18b20. four-core cable is used to form a tree-like or star-like network, in which 54 digital temperature sensors existing on 18 fermentation tanks can be connected.the quantity of junction wires between temperature sensor and computer will be reduced greatly.temperature detector pro

5、vides power supply for bus converter and ds18b20 through four-core cable. because bus converter has used hardware fault detecting technology, the fault temperature sensor can automatically detach from the main bus and will not affect normal working of other sensor in network. so to solve the problem

6、 of a certain sensor or branchs damage causing the paralysis of entire bus. the length of detecting temperature bus can reach more than 500 meters. these all make system maintenance and expansion easy. the experiments show that this system is characterized by high intelligence, high-precision, capab

7、ility of making temperature test on multi-points and compensating function. the method has a good applicable value to the temperature test.introduction the change of fermentation temperature has a greater impact on the quality of beer in the process of beer production. many fermentation tanks are us

8、ed to ferment beer in a brewery. a few sensors are installed in each fermentation tank to measure the temperature of liquid. the temperature monitoring system is characterized by greater number of temperature measurement points, the temperature measurement points are relatively concentrated.the trad

9、itional temperature detection system is composeof sensor, transmitter, a/d converter and so on. when there exist many detected points, the more transmitter and junction wires are needed, which not only makes the cost increase, and also brings us many inconvenience. dallas corp of united states first

10、 produced 1-wire digital temperature sensor ds1820, and then an enhanced product ds18b20 is released. the ds18b20 is a kind of digital temperature sensor of high integration, which consists of 64-bit laser rom, temperature sensor, 1-wire interface, scratchpad ram, temperature alarm triggers th and t

11、l, 8-bit crc generator, control logic and parasitic power 1. the measuring temperatures of ds18b20 is range from -55c to +125c, which precision is 0.5c and resolution is programmable from 9 to 12 bits. it adopts 3-pin (gnd, dq, vdd), to-92 package. each ds18b20 has the unique 64-bit laser rom addres

12、s code 1. a lot of ds18b20 can be connected to the same bus to detect the temperature without any external components. this feature is very well suitable for multi-point distributed temperature detection, and is convenient to constitute bus-type temperature detection system.the composition of the sy

13、stem the composition of temperature monitoring system of beer fermentation is shown in figure 1. industrial computer is responsible for the work of displaying temperature data, generating the curve of temperature change, and temperature chart printing and so on. temperature detector can be connected

14、 to industrial computers through the rs-232 interface. it controls the working condition of all the temperature sensors through transmission bus, and collects temperature data of 18 fermentation tanks in accordance with industrial computer commands. temperature detector is connected to 3 bus convert

15、er through the transmission bus, each bus converter can be connected to 6 fermentation tanks; there are 3 temperature sensors (ds18b20) in each fermentation tank. the temperature monitoring system contains 54 temperature measurement points in 18 fermentation tanks. transmission bus adopts the four-c

16、ore cables;temperature detector provides power supply for bus converter and ds18b20 through transmission bus. there is a bus driver in temperature detector; it can drive more than 500 meters transmission bus. if you need increase the number of temperature measurement points, more bus converters can

17、be connected to transmission bus in order to achieve linking of more ds18b20s. the number of the ds18b20 can be connected up to more than 300 at most.the design of temperature detector the composition of the temperature detector is shown in figure 2, at89c51 microcontroller is the core of the temper

18、ature detector to control the work of the various circuits. control program is stored in the mcus internal program memory. data memory saves the temperature data of each detection point. 64-bit code memory saves laser rom code of each temperature sensor (ds18b20). mcus serial signals are converted t

19、o rs-232c standard through rs-232 interface to realize the connection of industrial computer and the temperature detector. bus driver extends the driving capability of mcus i/o port to drive the transmission bus, in order to obtain further transmission distance. watchdog and reset circuit can provid

20、e power-on reset for the microcontroller, they can also provide reset signal when program has been confused by accidentally interfering. display is used to show the current number of fermentation tanks and temperature value of 3 sensors in fermentation tanks. the keyboard is used to control the temp

21、erature detector starting and stopping, but also enter the testing cycle and other control parameter.temperature detector can work independently, and display the number of fermentation tank and temperature value of 3 detected points in this tank, the range of temperature shown is -19.9c 99.9c. the n

22、umber of tank shown can automatically change in cycle. time shown can be set arbitrarily during 199 seconds. temperature detector is also able to accept orders of industrial computer, it transmits the temperature value to the industrial computer, and then the industrial computer completes data proce

23、ssing. the design of bus driver and bus converter theoretically, lots of ds18b20s can be connected to one bus in parallel. however, the operating time slot of ds18b20 is fixed, and the width of many control impulses is so narrow that it is only few microseconds. in fact, we can seldom meet the need

24、of the operating time slot of ds18b20 because of the limit of driving ability and distributing parameters. especially the increase of distributing capacitance of the over-long bus will make the distortion of waveform unavoidable, so the read/write error occurs. the recommended length of the bus by t

25、he dallas corporation is only 100 meters, and 20 ds18b20s can be connected to it at same time, hence, the application is limited 2,4. in order to solve this problem, we have designed transmission bus and its driver. the composition of bus driver and bus converter is shown in figure 3. transmission b

26、us includes two signal lines txd and rxd. bus driver adopts 74hc367-type logical circuit to expand the driving ability of txd port in at89c51, thus it completes to drive txd line of transmission bus. the length of bus can be reached 500 meters. multiple bus converters can be connected to a transmiss

27、ion bus to form “tree” or “star” network. bus converter connects the transmission bus and the temperature sensor ds18b20 and completes the signal conversion between them. ds18b20 return signal is transmitted to the terminal rxd of the bus through the driver. the driver in bus converter also uses 74h

28、c367-type logic circuit.the driver we mention here is different with the address switch of dallas corporation microlans network 3. the drivers on the bus are all connected to each other. when the skipping rom command is sent to ds18b20s, all ds18b20s existing on the bus can receive it. this feature

29、allows us to start temperature conversion of all the ds18b20s existing on the same bus. the temperature detector can acquire the temperature of the different serial number detecting-point by sending different address. this will greatly reduce the temperature detection cycle, thereby increasing the t

30、emperature detection speed.the technology of hardware fault detecting when one power line or data line of any ds18b20 in the system is short to the ground, it will cause the whole bus stop working. to avoid this problem, we have designed hardware fault detecting and processing circuits for the syste

31、m. on the one hand, it limits the short circuit current under 10ma; on the other hand disconnects the failure branch from the transmission bus. the composition of hardware fault detecting and processing circuit see figure 3. fault detecting circuit tests the logic level of 1-wire interface, when the

32、 logic level is high, its output signal is “1”and driver of converter is shutdown; when the logic level is low, its output signal is “0” and driver of converter is open. if logic level is low and its duration is more than 10ms, according to these phenomena, we can judge hardware failure occurring, t

33、emporality, the output signal is “1”, and the driver of converter will be a permanent shutdown. thus, only failure ds18b20 is disconnected from transmission bus, the other ds18b20s can work normally.although a bus converter can be connected to 30 ds18b20s, when short-circuit fault occurs in one of d

34、s18b20s, the other 29 ds18b20s will stop working. if each ds18b20 can work independently and it has no effect to others when there is short-circuit fault occurring in one of them, it is necessary for each ds18b20 equipped with a bus converter. one transmission bus can connect more than 300 converter

35、s. the design of management software software of the temperature monitoring system is developed under visual basic 6.0, it is responsible for the work of acquiring real-time temperature, sensor temperature compensating,displaying multi-point temperature value, showing temperature variation curve, th

36、e temperature value statements and the temperature variation curve printing. module of acquiring real-time temperature is realized through serial communication between the industrial computer and temperature detector. serial communication adopts rs-232c standard, the baud rate of data transfer is th

37、e 9600 bit/s, the data format is 8 data bits, 1 parity bit, and 1 stop bit. industrial computer collects temperature value of 54 test points in 18 fermentation tanks once every 1 minute, then temperature data is saved in the computer hard disk in the format of a text file, in order to generate the t

38、emperature statements and curves of temperature change.module of sensor temperature compensating is used to calibrate error of the sensor. it is 0.5c accuracy from -10c to +85c in ds18b20 1. in order to improve the measurement accuracy, we have set up temperature compensation for each one temperatur

39、e measurement point in the management software. the range of temperature compensation is 5c, the resolution is 0.01c. temperature compensation data requires to be inputted manually.module of displaying multi-point temperature value is used to display the current temperature of the 54 test points in

40、the 18 fermentation tanks; the display interface is shown in figure 4. you can find the number of fermentation tanks and temperature value of the three test points in fermentation tanks from monitor. three test points are ranked by the upper, middle and lower. the interface contains quick button of

41、temperature curve, by clicking on the mouse, you can switch to the display interface of temperature change curve. it also displays the communications status and the number of the fermentation tank in which the temperature data is being sampled.conclusion with the use of digital temperature sensor ds

42、18b20, a tree-like or star-like network topology is achieved, which simplifies the hardware design of the temperature monitoring system and reduces the cost of system. hardware fault detection technology and its continuous improvement make the reliability of temperature detection system greatly impr

43、oved. bus driver and bus converters adopt 74hc series logic circuits, with very low static power consumption. the temperature monitoring system has been running for more than four years. the practice shows that the system is simple in connecting wire,convenient in maintenance, and is also low cost,

44、high dependability and good effect. it has excellent application prospect. references 1 dallas semiconductor, ds18b20 programmable resolution 1-wire digital thermometer. (2003) 2 dallas semiconductor, microlan - in the long run, application note 108. (2001) 3 dallas semiconductor, complex microlans,

45、 application note 106. (2001) 4 dallas semiconductor, guidelines for reliable 1-wire networks, application note 148. (2002) advanced materials research vols. 108-111 (2010) pp 898-902 (2010) trans tech publications, switzerlanddoi:10.4028/基于ds18b20的啤酒發(fā)酵溫度測控系統周芬萍 馬鴻濤 隋秉棟 孫佳莫 河北工業(yè)大學信息科學與工程學院 中國，河北，石家莊

46、050054 zhoufenping mahongtao suibd sunjiamo摘 要：本文介紹了一種在啤酒發(fā)酵時使用的溫度檢測系統。溫度監(jiān)控系統拓撲總線結構的特點是由工業(yè)計算機、溫度檢測器、總線轉換器、傳輸總線、1-wire數字溫度傳感器ds18b20組成。四芯電纜是用來形成一個樹形或星形網絡，其中，存在于18發(fā)酵罐的54個數字溫度傳感器可以連接。溫度傳感器和計算機之間的連接導線的數量將大大減少。溫度檢測器提供電源通過四芯電纜為總線轉換器和ds18b20。因為總線轉換器采用了硬件故障檢測技術，故障溫度傳感器可以從主總線自動分離，不會影響其他傳感器的正常工作網絡。因此解決了某個傳感器或分

47、支的損傷引起的整個總線癱瘓的問題。檢測溫度總線長度可達到500米以上。這些都使系統維護和擴展方便。實驗表明，該系統的特點是高智能、高精度、多路溫度檢測的能力、補償功能。該方法具有良好的應用價值對于溫度檢測。關鍵詞：ds18b20，溫度檢測，啤酒發(fā)酵，總線驅動，故障檢測介紹 在啤酒生產過程中溫度的變化對啤酒的質量有較大的影響。在釀酒廠啤酒發(fā)酵時會用許多發(fā)酵罐，可以在每個發(fā)酵罐安裝幾個傳感器來測量液體的溫度。溫度監(jiān)控系統的特征在于擁有大量的溫度測量點，但測溫點比較集中。傳統的溫度檢測系統由傳感器、變送器、a / d轉換器等等組成。當存在著許多檢測點，需要更多的發(fā)射器和結線，這不僅使成本增加，同時也

48、給我們帶來了許多不便。美國dallas股份有限公司首次生產1-wire數字溫度傳感器ds1820 ，然后升級版產品ds18b20出產。該ds18b20是一種高集成度，它由64位的光刻rom 、溫度傳感器、1-wire接口、暫存ram 、溫度報警觸發(fā)器th和tl 、 8位crc生成器、控制邏輯和寄生功率 1 組成。ds18b20的溫度測量范圍從-55c至+125c ，其中精度為 0.5 ，分辨率為可編程的9至12位。它采用3引腳（gnd ，dq ，vdd ），to-92封裝。每ds18b20具有獨特的64位激光rom地址碼 1 。很多ds18b20可以連接到同一總線上檢測溫度，無需任何外部元件。

49、這個功能非常適合于多點分布式溫度檢測，并且可以方便地構成總線型的溫度檢測系統。系統組成啤酒發(fā)酵的溫度監(jiān)測系統的組成如圖1示。工業(yè)計算機負責顯示溫度數據處理工作，生成溫度變化曲線和打印溫度圖表等。溫度檢測儀可通過rs- 232接口連接到工業(yè)計算機。它通過傳輸總線控制所有溫度傳感器的工作狀態(tài)，并根據工業(yè)計算機的命令收集18個發(fā)酵罐的溫度數據。溫度檢測器通過傳輸總線連接到總線轉換器中，每個總線轉換器可以連接到6個發(fā)酵罐；每個發(fā)酵罐有3個溫度傳感器（ds18b20 ）。該溫度監(jiān)控系統在18發(fā)酵罐上分布了54個溫度檢測點。傳輸總線采用四芯電纜，溫度檢測器通過傳輸總線提供電源為總線轉換器和ds18b20

50、。它可以驅動超過500米的傳輸總線。如果你需要增加溫度測量點的數目，多總線轉換器可以連接到傳輸總線，以便實現連接更多ds18b20。 ds18b20的數量可以被連接到超過300個。圖1 溫度檢測系統的組成溫度檢測儀的設計 溫度檢測器的組成于圖2中示，at89c51單片機是溫度檢測器控制各種電路工作的核心?？刂瞥绦虼鎯υ趩纹瑱C的內部程序存儲器中。數據存儲器保存每個的溫度檢測點數據。 64位程序存儲器保存每個溫度傳感器（ds18b20）的激光rom代碼。圖2溫度探測器組成的框圖mcu的串行信號通過rs-232接口轉換為rs-232c標準，實現了工業(yè)計算機及溫度檢測器的連接。公交車司機擴展了駕駛mc

51、u的i / o端口來驅動總線的傳輸，以便獲得進一步的傳輸能力距離?？撮T狗和復位電路可以提供上電復位微控制器，它們也可以提供復位信號，當程序被混淆了意外干擾。顯示器是用來表明發(fā)酵罐和3個傳感器在發(fā)酵溫度值的當前數量坦克。鍵盤用于控制溫度檢測器啟動和停止，也進入測試周期等控制參數。溫度檢測器可以獨立工作，并顯示發(fā)酵罐的數量和的3個溫度值的檢測點在該罐中所示的溫度范圍是-19.9 c99.9 c。示槽的數目可以自動改變周期。顯示時間可設置在1 99秒隨意。溫度檢測器也能夠接受的工業(yè)訂單計算機，它發(fā)送該溫度值的工業(yè)計算機，然后在工業(yè)計算機完成數據處理?？偩€驅動器和總線轉換器設計理論理論上，大量的ds1

52、8b20芯片可以連接到一個總線上。然而，ds18b20的操作時段是固定的，并且許多控制脈沖的寬度是如此之窄，只有幾微秒。事實上，我們很少能滿足ds18b20的操作時段的需要，因為運行能力和分布參數的限制。尤其是增加散發(fā)的過度長的總線的電容會使波形的失真是不可避免的，所以發(fā)生讀/寫錯誤。dallas公司總線的長度建議只有100米，20 個ds18b20可以連接到它在同一時間，因此，該應用程序是有限制的2,4 。為了解決這個問題，我們設計了傳輸總線和它的驅動程序。該總線驅動器和總線轉換器的組成如圖3所示。傳輸總線包括兩個信號線txd和rxd ?？偩€驅動采用74hc367型邏輯電路，擴大驅動txd端口在單片機at89c51的能力，從而完成對驅動txd線的傳輸總線。該總線長度可以達到500米。多個總線轉換器可以連接到一個傳輸總線，形成“樹”型或“星”型的網絡。總線轉換器連接傳輸總線和溫度傳感器 ds18b20 和完成它們之間的信號轉換。 ds18b20返回的信號通過驅動器發(fā)送到總線的端子rxd 。在總線驅動器轉換器還采用74hc367型邏輯電路。圖 3總線驅