【正文】 y choose the noncontact IC card generally. If altogether male automobile charge, highway bridge charge, automatic general entrance guard control and so on. Noncontact IC card effective range。 畢業(yè)設(shè)計小結(jié)。無 錫 職 業(yè) 技 術(shù) 學(xué) 院 畢業(yè)設(shè)計任務(wù)書 1 無 錫 職 業(yè) 技 術(shù) 學(xué) 院 畢 業(yè) 實 踐 任 務(wù) 書 課 題 名 稱 基于單片機的自行車?yán)锍?/速度表設(shè)計 指 導(dǎo) 教 師 徐 明 職 稱 工程師 指 導(dǎo) 教 師 黃 從 貴 職 稱 講 師 專 業(yè) 名 稱 電子工藝與管理 班 級 電子工藝 20631 學(xué) 生 姓 名 寧 翠 萍 學(xué) 號 2031063121 課題需要完成的任務(wù)： 設(shè)計一個自行車?yán)锍?/速度表，以單片機 AT89C51 為核心，實現(xiàn)實時測量并顯示自行車行駛過程中的兩項運動參數(shù)：速度和里程。超速行駛（設(shè)置限速參數(shù)）時，能自動發(fā)出聲光報警。 IC card readwrite machines and tools choice and design。s contact form. In (4) consideration application system the cardholder operates the behavior (service person to operate or cardholder voluntarily operates) 無 錫 職 業(yè) 技 術(shù) 學(xué) 院 畢業(yè)設(shè)計說明書（英文翻譯） 7 the influence which possibly creates to the system safety, chooses whether needs to spring the control or other housekeeping operation function automatically. (5) Consideration card arriving signal positions Chang Kai Xing or often close mold , in order to coordinates the machines and tools well the circuit design and data gathering and the control. work connection choice Here work architecture refers to the work connection function which IC card readwrite machines and tools itself supports. In the practical application system, between the IC card terminal device data piles with the data transfer also often uses the work mailing address. It self has installed the work connection in many specialpurpose IC card readwrite machines and tools. Synthesizes each kind of machines and tools the design and the actual system use situation, at present IC card readwrite machines and tools itself has the work connection is generally RS 232 connections or the standard RS485 connection, may support constitutes the small scope main line structure or travels at night the structure the confined work. Regarding has the accurate RS232 connection or standard RS232 the connection IC card readwrite machines and tools and the microputer together through together the multiuser interface control extender board, in under the multiuser software support, may constitute a small scope to travel at night the structure the work system. Multiuser control extender board uses which for the microputer, has the Chinese red army soldier or 16 groups serial port expansion ability generally. In the actual course of munications, the star type structure has realized the pointtopoint correspondence connection. The signal distance is a RS232 connection existence question. At present may use the solution is direct Canada ties the longline driver to increase the connection driving force. Regarding has standard RS485 the connection IC card readwrite machine and the microputer together through together the RS485 specialpurpose control extender board, in actuates the software correspondingly under the support, may constitute a main line structure work system.. The RS485 control panel uses which for the microputer has Shan Kou Huo generally the pair of mouth connection. Each single mouth may hang the knot 32 terminals. If is the pair of mouth output, then may bring two main lines, namely altogether may hang meets 64 terminals. In the main line way, various terminal device all is hangs parallel meets on the main line, therefore in information transmission time, assumes the broadcast way. Namely when an equipment transmits the information to the main line on, on all main line equipment has the opportunity to obtain the information. That equipment which but obtains the information equipment only to be able truly to be the equipment address with which transmits the information 無 錫 職 業(yè) 技 術(shù) 學(xué) 院 畢業(yè)設(shè)計說明書（英文翻譯） 8 is assigned the address tallies. Is away from with the RS485 control panel direct drive may reach generally. In summary, wants to enable a cartoon system to achieve the best use effect, must select the corresponding IC card type, the readwrite machines and tools, Booth and so on. A more important creation unobstructed reliable correspondence work, it is radically selects any standard the correspondence medium. 3. Concluding remark intellectualization IC card is the world changes with each new day now in the development information a dazzling nova, it is to the market, the modity, the currency and the transaction way transformation, it will affect and changes people39。信息在介質(zhì)中的分布可理解為立體型的。同時也減少了擔(dān)心數(shù)據(jù)可能變化或丟失而進行刷新和備份工作。 (2)一般的軟件邏輯加密方式：即采用特征字混合編碼或采用明碼加檢測字校驗的處理或直接采用密文編碼，都可以比較方便地使卡片中存儲的信息達到較好的加密性能。隨著技術(shù)的發(fā)展，這種優(yōu)勢還將進一步發(fā)展和擴大。如共公汽車收費、路橋收費、自動通行門禁控制等等。 非接觸型 IC 卡的產(chǎn)品品種并不很多，表 1 是幾種非接觸型 IC 卡的一些性能。 IC 卡容量的選擇 較常用的帶 CPU 型 IC 卡的存儲器容量為： ROM 存儲器的容量一般在 4k～ 16k 字節(jié)間； RAM 存儲器的容量一般在 128～ 512 個字節(jié)之間； EEPROM 存儲器的容量一般在 1k～ 8k字節(jié)之間。 IC 卡讀寫機具的選擇 IC 卡的讀寫機具從總體來說可分為兩大類： 專用型 IC 卡讀寫機具和通用性 IC 卡讀寫機具。 (4)考慮應(yīng)用系統(tǒng)中持卡人操作行為 (服務(wù)員操作或持卡人自行操作 )對系統(tǒng)安全可能造成的影響，選擇是否需要自動彈 出控制或其他輔助操作功能。在實際的通信過程中，星形結(jié)構(gòu)實現(xiàn)了點對點的通信連接。即當(dāng)一個設(shè)備向總線上發(fā)送信息時，所有總線上的設(shè)備均有機會得到信息。 無 錫 職 業(yè) 技 術(shù) 學(xué) 院 調(diào)研報告 13 調(diào)研報告 自行車 速度里程表 據(jù)資料顯示， 2020 年我國道路交通死亡人數(shù)為 104372 人，其中騎自行車者占死亡人數(shù)的 %。據(jù)調(diào)查顯示，上海市居民1986 年出行方式中步行占 41%，自行車占 30%。但有些因素也阻止了人們的交通需 求。而這些群體在交通活動中活動難度的加大，必然限制他們參與交通活動的范圍。 自行車駕駛 員 自身原因 。由于表盤指針偏轉(zhuǎn)程度正比于軟軸的轉(zhuǎn)動時產(chǎn)生的磁力，當(dāng)轉(zhuǎn)速較低的時候，磁力較小，隨轉(zhuǎn)速變化波動較大。但現(xiàn)在很多的自行車都加上了里程表，且跟隨汽車?yán)锍瘫淼男⌒突?，電子化，現(xiàn)在在自行車或者電動自行車上安裝里程表已是很容易，且增加里程表的電動自行車能 給用戶帶來很多方便，比如充滿一次電能行駛多遠(yuǎn)的路程，計算出剩余電量大概還能行駛多遠(yuǎn)。對待測信號進行放大的目的是降低對待測信號的幅度要求；波形變換和波形整形電路則用來將放大的信號轉(zhuǎn)換成可與單片機相連的 TTL 信號；通過單片機的設(shè)置可使內(nèi)部定時器 T1 對脈沖輸入引腳 T0進行控制，這樣能精確地算出加到 T0 引腳的單位時間內(nèi)檢 測到的脈沖數(shù)；設(shè)計中速度顯示采用 LED 模塊，通過速度換算得來的里程數(shù)采用 I2C總線并通過 E2PROM 來存儲，既節(jié)省了所需