基于ds18b20的啤酒發(fā)酵溫度測控系統(tǒng)畢業(yè)設(shè)計(jì)外文資料翻譯

1、<p><b>　　中文3200字</b></p><p>　　畢業(yè)設(shè)計(jì)外文資料翻譯</p><p>　　題 目 基于DS18B20的啤酒發(fā)酵 </p><p>　　溫度測控系統(tǒng) </p><p>　　學(xué) 院 自動(dòng)化與電氣工程學(xué)院 </p&

2、gt;<p>　　專 業(yè) 自動(dòng)化 </p><p>　　班 級(jí) 自動(dòng)化xxxx班 </p><p>　　學(xué) 生 xxxxxxxxx </p><p>　　學(xué) 號(hào) 20100321166

3、 </p><p>　　指導(dǎo)教師 xxxxx </p><p>　　二〇一四年三月三十一日</p><p>　　Advanced Materials Research Vols. 108-111 (2010) pp 898-902</p><p>　　© (2010)

4、Trans Tech Publications, Switzerland</p><p>　　doi:10.4028/www.scientific.net/AMR.108-111.898</p><p>　　Temperature Detecting System of Beer Fermentation</p><p>　　Based on DS18B20<

5、/p><p>　　Fen-Ping Zhou, Hong-Tao Ma, Bing-Dong Sui，and Jia-Mo Sun</p><p>　　College of Information Science & Engineering, Hebei University of Science and Technology</p><p>　　Hebei,

6、Shijiazhuang 050054, China</p><p>　　zhoufenping@hebust.edu.cn,mahongtao@hebust.edu.cn</p><p>　　suibd@hebust.edu.cn,sunjiamo@hebust.edu.cn</p><p>　　Keywords: DS18B20, Temperature Det

7、ecting, Beer Fermentation, Bus-driving, Fault Detecting </p><p>　　Abstract. This Paper introduces a temperature detection system in beer fermentation. A temperature monitoring system with characteristics of

8、bus topology structure is composed of industrial computer, temperature detector, bus converter, transmission bus and especially 1-wire digital temperature sensor DS18B20. Four-core cable is used to form a tree-like or st

9、ar-like network, in which 54 digital temperature sensors existing on 18 fermentation tanks can be connected.The quantity of junction wire</p><p>　　Introduction </p><p>　　The change of fermenta

10、tion temperature has a greater impact on the quality of beer in the process of beer production. Many fermentation tanks are used to ferment beer in a brewery. A few sensors are installed in each fermentation tank to meas

11、ure 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 traditional temper

12、ature detection system is compose</p><p>　　of 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

13、 cost increase, and also brings us </p><p>　　many inconvenience. DALLAS Corp of United States first produced 1-wire digital temperature sensor DS1820, and then an enhanced product DS18B20 is released. The DS

14、18B20 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 TL, 8-bit CRC generator, cont

15、rol logic and parasitic power [1]. The measuring temperatures of DS18B20 is range from -55°C to +125°C, which precis</p><p>　　The Composition of the System </p><p>　　The composition

16、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 cha

17、rt printing and so on. Temperature detector can be connected to industrial computers through the RS-232 interface. It controls the working condition of all the temperature sensors through transmission bus, and collects

18、 temperature data of 18 fermentation tanks </p><p>　　The Design of Temperature Detector </p><p>　　The composition of the temperature detector is shown in Figure 2, AT89C51 microcontroller is th

19、e core of the temperature detector to control the work of the various circuits. Control program is stored in the MCU's internal program memory. Data memory saves the temperature data of each detection point. 64-bit c

20、ode memory saves laser ROM code of each temperature sensor (DS18B20). </p><p>　　MCU's serial signals are converted to RS-232C standard through RS-232 interface to realize the connection of industrial co

21、mputer and the temperature detector. Bus driver extends the driving capability of MCU's I/O port to drive the transmission bus, in order to obtain further transmission distance. Watchdog and reset circuit can provide

22、 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 th</p><p>　　Temperature detector can work indep

23、endently, and display the number of fermentation tank and temperature value of 3 detected points in this tank, the range of temperature shown is -19.9°C ~ 99.9°C. The number of tank shown can automatically cha

24、nge in cycle. Time shown can be set arbitrarily during 1~99 seconds. Temperature detector is also able to accept orders of industrial computer, it transmits the temperature value to the industrial computer, and then th

25、e industrial computer completes dat</p><p>　　The Design of Bus Driver and Bus Converter </p><p>　　Theoretically, lots of DS18B20s can be connected to one bus in parallel. However, the operating

26、 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 of the operating time slot of DS18B20 because of the limit of dr

27、iving 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 e</p><p>　　The driver w

28、e 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 exi

29、sting on the bus can receive it. This feature 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 d

30、etecting-point by sending different address. Thi</p><p>　　The Technology of Hardware Fault Detecting </p><p>　　When one power line or data line of any DS18B20 in the system is short to the groun

31、d, it will cause the whole bus stop working. To avoid this problem, we have designed hardware fault detecting and processing circuits for the system. On the one hand, it limits the short circuit current under 10mA; on t

32、he 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 leve</p><p>　　

33、Although a bus converter can be connected to 30 DS18B20s, when short-circuit fault occurs in one of DS18B20s, the other 29 DS18B20s will stop working. If each DS18B20 can work independently and it has no effect to others

34、 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 converters. </p><p>　　The Design o

35、f 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 mult

36、i-point temperature value, showing temperature variation curve, the temperature value statements and the temperature variation curve printing. </p><p>　　Module of acquiring real-time temperature is realize

37、d through Serial communication between the industrial Computer and temperature detector. Serial communication adopts RS-232C standard, the baud rate of data transfer is the 9600 bit/s, the data format is 8 data bits, 1 p

38、arity 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 f

39、ile, in </p><p>　　Module of sensor temperature compensating is used to calibrate error of the sensor. It is ±0.5°C accuracy from -10°C to +85°C in DS18B20 [1]. In order to improve the mea

40、surement accuracy, we have set up temperature compensation for each one temperature measurement point in the management software. The range of temperature compensation is ±5°C, the resolution is 0.01°C. Te

41、mperature compensation data requires to be inputted manually.</p><p>　　Module of displaying multi-point temperature value is used to display the current temperature of the 54 test points in the 18 fermentati

42、on 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 u

43、pper, middle and lower. The interface contains quick button of temperature curve, by clicking on the mouse, you can switch to the display interf</p><p>　　Conclusion </p><p>　　With the use of dig

44、ital temperature sensor DS18B20, 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 t

45、echnology and its continuous improvement make the reliability of temperature detection system greatly improved. Bus driver and bus converters adopt 74HC series logic circuits, with very low static power consumption. The

46、temperature monitoring system has been ru</p><p>　　References </p><p>　　[1] Dallas Semiconductor, DS18B20 Programmable Resolution 1-Wire Digital Thermometer. (2003) </p><p>　　[2] D

47、allas Semiconductor, MicroLAN - In the Long Run, Application Note 108. (2001) </p><p>　　[3] Dallas Semiconductor, Complex MicroLANs, Application Note 106. (2001) </p><p>　　[4] Dallas Semiconduct

48、or, Guidelines for Reliable 1-Wire Networks, Application Note 148. (2002) </p><p>　　Advanced Materials Research Vols. 108-111 (2010) pp 898-902</p><p>　　© (2010) Trans Tech Publications, Sw

49、itzerland</p><p>　　doi:10.4028/www.scientific.net/AMR.108-111.898</p><p>　　基于DS18B20的啤酒發(fā)酵溫度測控系統(tǒng)</p><p>　　周芬萍 馬鴻濤 隋秉棟  孫佳莫 河北工業(yè)大學(xué)信息科學(xué)與工程學(xué)院   中國，河北，石家莊050054 zhoufe

50、nping@hebust.edu.cn mahongtao@hebust.edu.cn suibd@hebust.edu.cn sunjiamo@hebust.edu.cn</p><p>　　摘 要：本文介紹了一種在啤酒發(fā)酵時(shí)使用的溫度檢測系統(tǒng)。溫度監(jiān)控系統(tǒng)拓?fù)淇偩€結(jié)構(gòu)的特點(diǎn)是由工業(yè)計(jì)算機(jī)、溫度檢測器、總線轉(zhuǎn)換器、傳輸總線、1-Wire數(shù)字溫度傳感器DS18B20組成。四芯電纜是用來形成一個(gè)樹形或星形網(wǎng)絡(luò)，其中

51、，存在于18發(fā)酵罐的54個(gè)數(shù)字溫度傳感器可以連接。溫度傳感器和計(jì)算機(jī)之間的連接導(dǎo)線的數(shù)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(zhuǎn)換器和DS18B20。因?yàn)榭偩€轉(zhuǎn)換器采用了硬件故障檢測技術(shù)，故障溫度傳感器可以從主總線自動(dòng)分離，不會(huì)影響其他傳感器的正常工作網(wǎng)絡(luò)。因此解決了某個(gè)傳感器或分支的損傷引起的整個(gè)總線癱瘓的問題。檢測溫度總線長度可達(dá)到500米以上。這些都使系統(tǒng)維護(hù)和擴(kuò)展方便。實(shí)驗(yàn)表明，該系統(tǒng)的特點(diǎn)是高智能、高精度、多路溫度檢

52、測的能力、補(bǔ)償功能。該方法具有良好的應(yīng)用價(jià)值對(duì)于溫度檢測。</p><p>　　關(guān)鍵詞：DS18B20，溫度檢測，啤酒發(fā)酵，總線驅(qū)動(dòng)，故障檢測</p><p><b>　　介紹 </b></p><p>　　在啤酒生產(chǎn)過程中溫度的變化對(duì)啤酒的質(zhì)量有較大的影響。在釀酒廠啤酒發(fā)酵時(shí)會(huì)用許多發(fā)酵罐，可以在每個(gè)發(fā)酵罐安裝幾個(gè)傳感器來測量液體的溫

53、度。溫度監(jiān)控系統(tǒng)的特征在于擁有大量的溫度測量點(diǎn)，但測溫點(diǎn)比較集中。傳統(tǒng)的溫度檢測系統(tǒng)由傳感器、變送器、A / D轉(zhuǎn)換器等等組成。當(dāng)存在著許多檢測點(diǎn)，需要更多的發(fā)射器和結(jié)線，這不僅使成本增加，同時(shí)也給我們帶來了許多不便。美國DALLAS股份有限公司首次生產(chǎn)1-Wire數(shù)字溫度傳感器DS1820 ，然后升級(jí)版產(chǎn)品DS18B20出產(chǎn)。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(bào)警

54、觸發(fā)器TH和TL 、 8位CRC生成器、控制邏輯和寄生功率</p><p>　　[ 1 ] 組成。DS18B20的溫度測量范圍從-55°C至+125°C ，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(dú)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

55、何外部元件。這個(gè)功能非常適合于多點(diǎn)分布式溫度檢測，并且可以方便地構(gòu)成總線型的溫度檢測系統(tǒng)。</p><p><b>　　系統(tǒng)組成</b></p><p>　　啤酒發(fā)酵的溫度監(jiān)測系統(tǒng)的組成如圖1示。工業(yè)計(jì)算機(jī)負(fù)責(zé)顯示溫度數(shù)據(jù)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(jì)算機(jī)。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(jù)工

56、業(yè)計(jì)算機(jī)的命令收集18個(gè)發(fā)酵罐的溫度數(shù)據(jù)。溫度檢測器通過傳輸總線連接到總線轉(zhuǎn)換器中，每個(gè)總線轉(zhuǎn)換器可以連接到6個(gè)發(fā)酵罐；每個(gè)發(fā)酵罐有3個(gè)溫度傳感器（DS18B20 ）。該溫度監(jiān)控系統(tǒng)在18發(fā)酵罐上分布了54個(gè)溫度檢測點(diǎn)。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(zhuǎn)換器和DS18B20 。它可以驅(qū)動(dòng)超過500米的傳輸總線。如果你需要增加溫度測量點(diǎn)的數(shù)目，多總線轉(zhuǎn)換器可以連接到傳輸總線，以便實(shí)現(xiàn)連接更多DS18B20。 DS

57、18B20的數(shù)量可以被連接到超過300個(gè)。</p><p>　　圖1 溫度檢測系統(tǒng)的組成</p><p><b>　　溫度檢測儀的設(shè)計(jì) </b></p><p>　　溫度檢測器的組成于圖2中示，AT89C51單片機(jī)是溫度檢測器控制各種電路工作的核心?？刂瞥绦虼鎯?chǔ)在單片機(jī)的內(nèi)部程序存儲(chǔ)器中。數(shù)據(jù)存儲(chǔ)器保存每個(gè)的溫度檢測點(diǎn)數(shù)據(jù)。 64位程序存儲(chǔ)器保

58、存每個(gè)溫度傳感器（DS18B20）的激光ROM代碼。</p><p>　　圖2溫度探測器組成的框圖</p><p>　　MCU的串行信號(hào)通過RS-232接口轉(zhuǎn)換為RS-232C標(biāo)準(zhǔn)，實(shí)現(xiàn)了工業(yè)計(jì)算機(jī)及溫度檢測器的連接。公交車司機(jī)擴(kuò)展了駕駛MCU的I / O端口來驅(qū)動(dòng)總線的傳輸，以便獲得進(jìn)一步的傳輸能力距離?？撮T狗和復(fù)位電路可以提供上電復(fù)位微控制器，它們也可以提供復(fù)位信號(hào)，當(dāng)程序被混淆了意外

59、干擾。</p><p>　　顯示器是用來表明發(fā)酵罐和3個(gè)傳感器在發(fā)酵溫度值的當(dāng)前數(shù)量坦克。鍵盤用于控制溫度檢測器啟動(dòng)和停止，也進(jìn)入測試周期等控制參數(shù)。溫度檢測器可以獨(dú)立工作，并顯示發(fā)酵罐的數(shù)量和的3個(gè)溫度值的檢測點(diǎn)在該罐中所示的溫度范圍是-19.9 °C?99.9 °C。示槽的數(shù)目可以自動(dòng)改變周期。顯示時(shí)間可設(shè)置在1 ? 99秒隨意。溫度檢測器也能夠接受的工業(yè)訂單計(jì)算機(jī)，它發(fā)送該溫度值的工業(yè)計(jì)

60、算機(jī)，然后在工業(yè)計(jì)算機(jī)完成數(shù)據(jù)處理。</p><p>　　總線驅(qū)動(dòng)器和總線轉(zhuǎn)換器設(shè)計(jì)理論</p><p>　　理論上，大量的DS18B20芯片可以連接到一個(gè)總線上。然而，DS18B20的操作時(shí)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(shí)上，我們很少能滿足DS18B20的操作時(shí)段的需要，因?yàn)檫\(yùn)行能力和分布參數(shù)的限制。尤其是增加散發(fā)的過度長的總線的電容會(huì)使波形的失真是不可避免

61、的，所以發(fā)生讀/寫錯(cuò)誤。DALLAS公司總線的長度建議只有100米，20 個(gè)DS18B20可以連接到它在同一時(shí)間，因此，該應(yīng)用程序是有限制的[2,4 ] 。為了解決這個(gè)問題，我們設(shè)計(jì)了傳輸總線和它的驅(qū)動(dòng)程序。該總線驅(qū)動(dòng)器和總線轉(zhuǎn)換器的組成如圖3所示。傳輸總線包括兩個(gè)信號(hào)線TXD和RXD ?？偩€驅(qū)動(dòng)采用74HC367型邏輯電路，擴(kuò)大驅(qū)動(dòng)TXD端口在單片機(jī)AT89C51的能力，從而完成對(duì)驅(qū)動(dòng)TXD線的傳輸總線。該總線長度可以達(dá)到500米。多

62、個(gè)總線轉(zhuǎn)換器可以連接到一個(gè)傳輸總線，形成“樹”型或“星”型的網(wǎng)絡(luò)?？偩€轉(zhuǎn)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(hào)轉(zhuǎn)換。 DS18B20返回的信號(hào)通過驅(qū)動(dòng)器發(fā)送到總線的端子RXD 。在總線驅(qū)動(dòng)器轉(zhuǎn)換器還采用74HC367型邏輯電路。</p><p>　　圖 3總線驅(qū)動(dòng)器和總線轉(zhuǎn)換器的組成</p><p>　　我們在這里提到的驅(qū)動(dòng)程序與DALLAS公司的MicroL

63、ANs網(wǎng)絡(luò)地址開關(guān)不同 [ 3 ] ?？偩€上的驅(qū)動(dòng)器都連接到彼此。當(dāng)跳過ROM命令發(fā)送到DS18B20 ，現(xiàn)有總線上的所有DS18B20s可以接收它。此功能讓我們開始所有的在同一總線上的DS18B20的溫度轉(zhuǎn)換。該溫度檢測器可以通過獲得的不同的序列號(hào)檢測點(diǎn)的溫度發(fā)送不同的地址。這將大大降低溫度檢測周期，從而提高了溫度檢測速度。</p><p><b>　　硬件故障檢測技術(shù)</b></p

64、><p>　　當(dāng)一個(gè)電源線或系統(tǒng)中的任何DS18B20的數(shù)據(jù)線是短到地面時(shí)，會(huì)引起整個(gè)總線停止工作。為了避免這個(gè)問題，我們設(shè)計(jì)了硬件故障檢測和該系統(tǒng)的處理電路。一方面，它限制下，以10mA的短路電流;另一方面斷開輸電母線故障分支。硬件故障檢測和處理電路的組成見圖3 。故障檢測電路，測試的1 -wire接口的邏輯電平，當(dāng)邏輯電平為高時(shí)，其輸出信號(hào)為“ 1”，并且驅(qū)動(dòng)轉(zhuǎn)換器的是關(guān)閉，當(dāng)該邏輯電平為低時(shí)，其輸出信號(hào)為“0”

65、和轉(zhuǎn)換器的驅(qū)動(dòng)器是打開的。如果邏輯電平為低，其持續(xù)時(shí)間為10ms以上，根據(jù)這些現(xiàn)象，可以判斷發(fā)生硬件故障，此時(shí)，輸出信號(hào)是“1” ，并且轉(zhuǎn)換器的驅(qū)動(dòng)器將永久性關(guān)閉。因此，只有失敗的DS18B20是從傳輸總線斷開，其他DS18B20可以正常工作。</p><p>　　雖然一個(gè)總線轉(zhuǎn)換器可以被連接到30個(gè)DS18B20 ，當(dāng)短路故障發(fā)生在一DS18B20時(shí)，其他29 個(gè)DS18B20也將停止工作。如果每一個(gè)DS18B

66、20可以獨(dú)立工作，也不會(huì)影響其它的，當(dāng)有短路故障的發(fā)生，為每一個(gè)DS18B20配備一個(gè)總線轉(zhuǎn)換器是必要的。這樣一個(gè)傳輸總線可以連接超過300個(gè)轉(zhuǎn)換器。</p><p><b>　　管理軟件的設(shè)計(jì)</b></p><p>　　溫度監(jiān)控系統(tǒng)的軟件是用VISUAL BASIC 6.0開發(fā)的，它負(fù)責(zé)采集實(shí)時(shí)溫度，傳感器溫度補(bǔ)償?shù)墓ぷ鳎@示多點(diǎn)溫度值，表示溫度變化曲線和溫度變化

67、曲線打印。</p><p>　　采集的實(shí)時(shí)溫度模塊之間通過串行通信實(shí)現(xiàn)和工業(yè)電腦及溫度檢測器的連接。串行通信采用RS-232C標(biāo)準(zhǔn)，數(shù)據(jù)傳輸波特率是9600比特/秒，數(shù)據(jù)格式為8位數(shù)據(jù)位，1個(gè)奇偶校驗(yàn)位，1位停止位。工業(yè)計(jì)算機(jī)收集18個(gè)發(fā)酵罐上的54個(gè)測試點(diǎn)的溫度值每1分鐘一次，然后將溫度數(shù)據(jù)保存在計(jì)算機(jī)硬盤中的文本文件中，以生成報(bào)表的溫度和溫度變化的曲線。 傳感器溫度補(bǔ)償模塊用于對(duì)傳感器進(jìn)行誤差校準(zhǔn)。

68、精度為± 0.5 °C從-10 ° C至+85 °C在DS18B20中[1] 。為了提高測量精度，我們建立了在每一個(gè)溫度測量點(diǎn)溫度補(bǔ)償管理軟件。溫度補(bǔ)償范圍為± 5 °C ，分辨率為0.01 ° C。溫度補(bǔ)償數(shù)據(jù)需要進(jìn)行手動(dòng)輸入。</p><p>　　顯示多點(diǎn)溫度值的模塊用于顯示在18個(gè)發(fā)酵罐中54個(gè)測試點(diǎn)的當(dāng)前溫度，顯示界面顯示在圖4 。你可

69、以找到發(fā)酵罐和三個(gè)測試點(diǎn)的溫度值在發(fā)酵罐的數(shù)量從監(jiān)視器。三個(gè)測試點(diǎn)是由上段，中段和下排。該接口包含溫度曲線的快捷按鈕，通過點(diǎn)擊鼠標(biāo)，就可以切換到顯示界面的溫度變化曲線。它也顯示通信狀態(tài)和的數(shù)發(fā)酵罐中的溫度數(shù)據(jù)被采樣。</p><p>　　圖4發(fā)酵溫度結(jié)論4的顯示界面</p><p><b>　　結(jié)論</b></p><p>　　通過使用數(shù)字溫度

70、傳感器DS18B20的樹狀或星狀網(wǎng)絡(luò)拓?fù)浣Y(jié)構(gòu)的實(shí)現(xiàn)，從而簡化了溫度監(jiān)測系統(tǒng)的硬件設(shè)計(jì)，降低了系統(tǒng)的成本。硬件故障檢測技術(shù)及其不斷改進(jìn)使溫度檢測系統(tǒng)的可靠性大大提高?？偩€驅(qū)動(dòng)器和總線轉(zhuǎn)換器采用74HC系列邏輯電路，具有非常低的靜態(tài)功耗。溫度監(jiān)視系統(tǒng)已經(jīng)運(yùn)行了四年多。實(shí)踐表明，該系統(tǒng)接線簡單，方便維護(hù)，成本低，可靠性高和高效率。它具有良好的應(yīng)用前景。</p><p><b>　　參考文獻(xiàn)</b>

71、</p><p>　　[1] Dallas Semiconductor, DS18B20 Programmable Resolution 1-Wire Digital Thermometer. (2003) </p><p>　　[2] Dallas Semiconductor, MicroLAN - In the Long Run, Application Note 108. (2001

72、) </p><p>　　[3] Dallas Semiconductor, Complex MicroLANs, Application Note 106. (2001) </p><p>　　[4] Dallas Semiconductor, Guidelines for Reliable 1-Wire Networks, Application Note 148. (2002) &l