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is rather much, and then the alternate test speed of the system decreases obviously, which influences the efficiency of the multipoint temperature test system seriously. In this paper, DS18B20 are hung on some I/O buses by grouping DS18B20 evenly, and the conversion temperature data is obtained by reading the state of DS18B20, then the system loss decreases and the alternate test speed increases obviously, which won’t influence the precision and the reliability of the conversion. A set of multipoint temperature test of artificial environment laboratory is achieved in this paper, which increases the test efficiency of the former system. 2. CHARACTERISTICS OF DS18B20 DS18B20 is the single bus digital temperature sensor from American Dallas Company. DS18B20 is consisted of the 64 figures ROM engraved by laser, the temperature sensitivity ponent, nonvolatile temperature alarms trigger (Device TH and TL).DS18B20 municates with the microprocessor by the single bus port and the test range of DS18B20 is from 55 centigrade to +125 centigrade, and the incremental value is centigrade. The temperature can be changed into figures within 720ms and each DS18B20 has the sole 64 figures serial number. Fig 1 DS18B20 64bit ROM The specific content is revealed as Fig 1: There are two 8 figures storages ( and ) for storing temperature value in DS18B20. storage stores plement of the temperature value, and stores symbols of the temperature value. The user can define nonvolatile temperature alarms sets and distinguish the alarms search order and seek the ponent temperature alarms state outside the scheduled limit. There are two alternative ways of power supply: Signal bus highlevel borrow power is adopted, or the +5v power supply externally is adopted directly. 3. APPLICATION THE GROUPING TEST METHOD This paper illustrates the grouping method with the interface of DS18B20 and 89C52. Assuming the amount of the buses on P1 port is 4 and the temperature test system needs 100 DS18B20 sensors, which can be distributed equally to the 4 I/O lines. If the number of sensors cannot be divided by the number of buses even, the number disparity of sensors on buses is no more than one, which can be handled while reading numbers. The power is supplied externally. Owning to the synchronistic conversion in each DS18B20, the intense current is needed, and the signal bus cannot be used for the power supply, otherwise the system cannot work in order. The schematic circuit is shown as Fig 2 (the DS18B20 signal buses of the same group are hung on some buses of P1 port). When read and write the DS18B20, the strict schedule must be kept. First a reversion pulse is sent to all DS18B20. After the reversion, Skip ROM order is sent to each circuit simultaneously from the I/O port, and the conversion order is sent, then all sensors begin transform. After the conversion, Match Rom order is sent to each circuit simultaneously, and 64 bits serial number is sent. DS18B20 is selected for each group, and Scratch Pad data is read. Finally the data is transformed. The data of serialread is transformed into the actual temperature value. One alternate test is finished after the DS18B20 temperature data is read pletely by the cyclical reading for 25 times. Fig 2 DS18B20 grouping sketch map Now the timeconsuming in the test system of the single bus and the grouping analyses method is illustrated respectively. The reversion time sequence and the time sequence of writing and reading one bit for the microprocessor are revealed in figures 46. The figure show: The reversion period of DS18B20 is 495us1020us。 2 一套無線多點(diǎn)溫度測(cè)試系統(tǒng)設(shè)計(jì) DS18B20 分組方法。無線模塊設(shè)置為睡眠狀態(tài),在在溫度的轉(zhuǎn)化率和轉(zhuǎn)化狀態(tài)數(shù)據(jù)傳輸。序號(hào) 120點(diǎn) DS18B20是讀通過鍵盤和顯示器的協(xié)調(diào)到 DS1225Y和編號(hào)。對(duì)于方便程序的調(diào)試和可靠性,采用模塊設(shè)計(jì),主要包括鍵盤處理模塊,無線通信模塊,溫度采集和處理,顯示模塊模塊等。當(dāng)過程中,必須被發(fā)送到一個(gè)脈沖信號(hào) MAX813 世界發(fā)展指標(biāo)“沒有比間隔為 到更多的引腳清除看門狗定時(shí)器。無線數(shù)字傳輸采用無線在整個(gè)接收發(fā)送形式 375 模塊,這 5 月有兩個(gè)業(yè)余頻段選擇和調(diào)節(jié)波特率(最大為 20Kbit/ S),單芯片微機(jī)串口的數(shù)據(jù)可以直接接 收。下位機(jī)收集數(shù)據(jù),存儲(chǔ)數(shù)據(jù),建立的 DS18B20,并發(fā)送無線模塊等。 設(shè)計(jì)示例 瀝青運(yùn)輸車輛是主要材料領(lǐng)域和道路之間的交通運(yùn)輸設(shè)備表面。一位讀期間以上 60us。 圖 2 DS18B20 的分組示意圖 現(xiàn)在,在單總線和分組分析法測(cè)試系統(tǒng)耗時(shí)分別說明。 DS18B20 是每個(gè)選擇組,便簽數(shù)據(jù)讀取。當(dāng)讀寫 DS18B20 的,嚴(yán)格的時(shí)間表被保留。如果傳感器的數(shù)量不能分割由總線數(shù)目甚至,傳感器的數(shù)量差距總線上是不超過一個(gè),它可以處理,而閱讀數(shù)字。用戶可以定義非揮發(fā)的溫度報(bào)警臺(tái)和區(qū)分報(bào)警搜索命令,并尋求組件溫度預(yù)定限額以外的報(bào)警狀態(tài)。 DS18B20 的通信微處理器單總線端口和測(cè)試范圍 DS18B20 是從 55 攝氏度到 +125 攝氏度,增量值是 攝 氏度。在本文中, DS18B20 的一些 I / O 總 線上都掛著分組 DS18B20 的均勻,溫度轉(zhuǎn)換獲取數(shù)據(jù)讀取 DS18B20 的狀態(tài), 系統(tǒng)損耗減少和替代測(cè)試速度增加顯然,這將不會(huì)影響精度和轉(zhuǎn)換的可靠性。 引言 由于結(jié)構(gòu)簡(jiǎn)單,安裝方便 ,低損失和廣泛的用途的溫度測(cè)試, DS18B20 溫度測(cè)試傳感器應(yīng)用領(lǐng)域,需要多點(diǎn)溫度測(cè)試,如化學(xué)工業(yè),糧食,環(huán)境監(jiān)督管理等。 (用外文寫 ) 附件 1:外文資料翻譯譯文 一種基于 DS18B20 的溫度探測(cè)系統(tǒng) 摘要 所有的 DS18B20 傳感器,用于多點(diǎn)溫度測(cè)試, IO 總線與 MCU 連接, 溫度數(shù)據(jù)的輪流收集。如果系統(tǒng)有大量的傳感器, MCU 的時(shí)間用在處理溫度數(shù)據(jù)明顯延長(zhǎng),因此周期替代測(cè)試變得更長(zhǎng)。因?yàn)橥ㄟ^一個(gè)DS18B20 的多點(diǎn)溫度測(cè)試系統(tǒng)總線,所有 DS18B20 是掛在一條總線上,然后每個(gè)溫度測(cè)試點(diǎn)的值轉(zhuǎn)換輪流讀。一套點(diǎn)對(duì)多點(diǎn)溫度,在此實(shí)現(xiàn)人工環(huán)境實(shí)驗(yàn)室測(cè)試,這增加了測(cè)試效率。溫度可在 720ms 的數(shù)字改為每個(gè) DS18B20 具有唯一的 64 數(shù)字序號(hào)。有兩個(gè)電源的替代方法:信號(hào)總線的高級(jí)別借采用電源或 +5V 外部電源直接采用。外部供電電源。首先回歸脈沖被發(fā)送到所有 DS18B20 的。最后的數(shù)據(jù)是轉(zhuǎn)化?;貧w時(shí)間序列和時(shí)間序列的寫作和閱讀的一個(gè)位微處理器在數(shù)字 46 中顯示。寫入或讀取下位跨度是微秒。不可避免的溫度,減少因?yàn)r青運(yùn)輸車輛的長(zhǎng)期工作和運(yùn)輸距離影響的攤鋪質(zhì)量路面,必須采取具體措施,根據(jù)殼的熱釋放。上位機(jī)采用 PC 機(jī),主要接收溫度數(shù)據(jù)從下位機(jī)上位機(jī)顯示,存儲(chǔ)和管理數(shù)據(jù)。 DS18B20 與電源,分為 8 組掛在 P1 口( 口)。如果間隔超過為 ,針并沒有收到脈沖信號(hào),然后 89C52 必須扭轉(zhuǎn)。外接電源回歸后, 89C52 首先自我檢查,然后分配給每個(gè)分支的程序模塊。首先,無線模塊設(shè)置為接收狀態(tài)接收收集參數(shù)和啟動(dòng)順序(傳輸內(nèi)容包發(fā)送 。包裝發(fā)送溫度數(shù)據(jù)和 DS18B20 的數(shù)字上位機(jī)系統(tǒng)中。這個(gè)系統(tǒng)是適用于瀝青運(yùn)輸?shù)募夹g(shù)改革一些國(guó)內(nèi)大型工程機(jī)械車輛實(shí)現(xiàn)公司和應(yīng)用程序的好成績(jī)。 the writing period of one bit is 60us120us。 the same content is sent for three times 。 A. 教育方針 B. 教育目的 C. 教學(xué)目標(biāo) D. 培養(yǎng)目標(biāo) 5.( )是教師最為常用的研究方法。 、過程與方法、情感態(tài)度與價(jià)值觀 、情感、意志 、面向未來、面向現(xiàn)代化 、人生觀、價(jià)值觀 ,提出了教育的最高目的是道德和性格的完善的教育學(xué)者是 ( )。 A. 場(chǎng)依存型 B. 場(chǎng)獨(dú)立型 C. 沖動(dòng)型 D. 沉思型 13. 人們對(duì)自己能否成功地從事某一行為的主觀判斷稱為 ( )。 17. 感覺對(duì)比是同一感受器接受而使感受性發(fā)生變化的現(xiàn)象,分和。 21. 課堂氣氛作為教學(xué)過程中的軟情境,通常是指課堂里某種占優(yōu)勢(shì)的與的綜合表現(xiàn)。 四、名詞解釋(本大題共 5 道小題,每小題 2 分,共 10 分) 25. 教學(xué) 26. 學(xué)校課程 27. 有意注意 28. 社會(huì)抑制 29. 學(xué)習(xí)策略 五、簡(jiǎn)答題(本大題共 5 道小題,每小題 4 分,共 20 分 ) 30. 為什么說學(xué)生具有發(fā)展的可能性與可塑性? 31. 促進(jìn)學(xué)生學(xué)習(xí)遷移的策略有哪些? 32. 簡(jiǎn)述影響社會(huì)知覺的特點(diǎn)。 七、教育寫作題( 16