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10uF的充放電電容。另外在電源端、電路板的四角等位置應(yīng)該跨接一個(gè)10~100uF的電容。 系統(tǒng)功能擴(kuò)展本系統(tǒng)由于個(gè)人能力的限制,在畢業(yè)設(shè)計(jì)結(jié)束之前只能作到現(xiàn)有的程度。在本次畢業(yè)設(shè)計(jì)的后期,我也盡量對(duì)本作品的功能進(jìn)行了相應(yīng)的擴(kuò)展。例如:?jiǎn)纹瑱C(jī)控制電器數(shù)量的增加,此部分充分應(yīng)用了單片機(jī)外圍接口擴(kuò)展技術(shù)或者加3-8譯碼器。這里對(duì)本系統(tǒng)還可以的擴(kuò)展功能做一下簡(jiǎn)單的介紹:使用MT8888芯片還可以進(jìn)一步擴(kuò)展其功能,而且使本裝置的體積大大減小,在這里就MT8888集成電路作一個(gè)簡(jiǎn)單的介紹。MT8888是MITEL公司的產(chǎn)品,是一種帶呼叫進(jìn)展過(guò)濾器的單片雙音多頻收發(fā)器。它包括一個(gè)帶增益可調(diào)放大器的DTMF接收器和一個(gè)DTMF發(fā)送器。接收器的結(jié)構(gòu)及工作原理與MT8870大同小異,也采用集頻帶分離濾波和數(shù)字解碼為一體的結(jié)構(gòu)。其中濾波電路也采用高頻群和低頻群兩個(gè)六階開(kāi)關(guān)電容帶通濾波器,解碼采用數(shù)字計(jì)數(shù)器技術(shù)來(lái)確定輸入的DTMF音調(diào)的頻率,并將其譯成標(biāo)準(zhǔn)的四位二進(jìn)制碼。發(fā)送器采用開(kāi)關(guān)電容D/A變換器。片內(nèi)使用了一個(gè)脈沖計(jì)數(shù)器,能合成精確的音調(diào)脈沖,保證音調(diào)脈沖準(zhǔn)確的定時(shí)發(fā)送。MT8888提供了一個(gè)標(biāo)準(zhǔn)的微處理器總線接口,可以直接與MCS51系列微機(jī)接口。它還可以選用呼叫進(jìn)展方式工作,通過(guò)呼叫進(jìn)展濾波器來(lái)檢測(cè)特定通帶內(nèi)的信號(hào)頻率,供微處理機(jī)或計(jì)數(shù)器電路分析,以確定檢測(cè)到的呼叫進(jìn)展音的性質(zhì)。MT8888的接收工作方式,從檢測(cè)DTMF信號(hào)到解碼的過(guò)程與MT8870完全一致,差異較大的是解碼后的二進(jìn)制碼的輸出。MT8888沒(méi)有延時(shí)導(dǎo)引輸出端SID,當(dāng)收到的有效音調(diào)對(duì)已被寄存且相對(duì)應(yīng)的四位二進(jìn)制碼已被鎖在接收數(shù)據(jù)寄存器中時(shí),片內(nèi)狀態(tài)寄存器中的延時(shí)控制標(biāo)志位B3復(fù)位,同時(shí)狀態(tài)寄存器中的接收數(shù)據(jù)寄存器滿標(biāo)志位B2置位,CPU可通過(guò)查詢這些狀態(tài)標(biāo)志來(lái)了解解碼的過(guò)程。如果選中的是中斷方式,當(dāng)延時(shí)控制標(biāo)志位復(fù)位時(shí),IRQ/CP端將變?yōu)榈碗娖剑駽PU發(fā)送中斷請(qǐng)求,當(dāng)CPU響應(yīng)此中斷,讀出狀態(tài)寄存器中的數(shù)據(jù)后,IRQ/CP端返回高電平狀態(tài)。根據(jù)MT8888的以上特點(diǎn),它可以檢測(cè)出電話振鈴音、忙音等信號(hào)音。新的系統(tǒng)功能,改進(jìn)了的系統(tǒng)可以首先工作于第二方式,即電話線路信號(hào)音檢測(cè)狀態(tài),然后根據(jù)振鈴情況控制摘掛機(jī),摘機(jī)后MT8888工作于第四方式,即雙音頻解碼狀態(tài),后面就和8870一樣了。這樣就能節(jié)省硬件電路的設(shè)計(jì)制作,還可以大大縮小本裝置整體體積。利用38譯碼器的STA、STB和STC還可以進(jìn)行級(jí)聯(lián)擴(kuò)展為24線譯碼器,若外接一個(gè)反向器還可以級(jí)聯(lián)擴(kuò)展成為32線譯碼器,從而實(shí)現(xiàn)對(duì)更多的外部受控設(shè)備進(jìn)行有效控制的可能。使用LM567鎖相環(huán)可以對(duì)電話信號(hào)音中的忙音進(jìn)行識(shí)別,使實(shí)際使用更加方便,而且能夠提高本裝置的穩(wěn)定性。千萬(wàn)不要?jiǎng)h除行尾的分節(jié)符,此行不會(huì)被打印。“結(jié)論”以前的所有正文內(nèi)容都要編寫(xiě)在此行之前。結(jié)論本課題是圍繞單片機(jī)控制技術(shù)在生產(chǎn)和生活中的應(yīng)用而開(kāi)展的,重點(diǎn)著重于“智能化”和“開(kāi)放性”。在研究課題開(kāi)始時(shí),我對(duì)遠(yuǎn)程控制技術(shù)、單片機(jī)原理、語(yǔ)音提示和DTMF技術(shù)等方面的資料進(jìn)行了系統(tǒng)的學(xué)習(xí)和研究。由于本系統(tǒng)的設(shè)計(jì)是在平時(shí)常用的實(shí)驗(yàn)設(shè)備儀器的基礎(chǔ)上進(jìn)行研究的,所以我對(duì)這些實(shí)驗(yàn)設(shè)備的硬件和軟件環(huán)境比較熟悉,從而便于對(duì)本設(shè)計(jì)進(jìn)行徹底的研究和剖析。因?yàn)樵诒鞠到y(tǒng)中選用了一些結(jié)構(gòu)簡(jiǎn)單但是性能可靠的硬件電路來(lái)實(shí)現(xiàn)部分功能,以及性價(jià)比很高的芯片,由于資料芯片多是英文資料,使我在設(shè)計(jì)中的難度加大。經(jīng)過(guò)有計(jì)劃的對(duì)相關(guān)知識(shí)的學(xué)習(xí)、強(qiáng)化,以及系統(tǒng)總體方案的制定,硬件電路圖的繪制,完成了本系統(tǒng)的硬件電路設(shè)計(jì)和部分軟件程序的編寫(xiě)。本系統(tǒng)設(shè)計(jì)的中央處理部分采用單片機(jī)AT89C51,語(yǔ)音提示芯片是ISD2590,TDMF雙音頻解碼芯片是MT8870等芯片,還采用了其他可靠元器件,如光控三極管、D觸發(fā)器、74SL04反相器、二極管等。本設(shè)計(jì)能夠滿足在家庭或其他無(wú)人堅(jiān)守崗位的實(shí)際應(yīng)用,并且具有以下的優(yōu)勢(shì): 采用硬件電路實(shí)現(xiàn)部分功能,從而是整個(gè)系統(tǒng)的性能更可靠。 使用靈活和操作方便。本系統(tǒng)既可作為嵌入部分,亦可作為獨(dú)立部分使用。 可擴(kuò)展性強(qiáng),升級(jí)方便。 適應(yīng)性強(qiáng),不僅可以完成一定范圍內(nèi)的實(shí)時(shí)控制,而且經(jīng)過(guò)改進(jìn)可以完成長(zhǎng)距離的控制應(yīng)用。但在本課題的設(shè)計(jì)中,由于課題時(shí)間有限,以及本人知識(shí)和實(shí)際設(shè)計(jì)經(jīng)驗(yàn)不足,本系統(tǒng)在硬件和軟件方面有很多不足之處,從而整個(gè)系統(tǒng)還有很多需要改進(jìn)和完善的地方,下一步的工作需要對(duì)其進(jìn)行深度優(yōu)化和細(xì)節(jié)處理。我想應(yīng)該從以下幾個(gè)方面: 優(yōu)化單片機(jī)的端口分配,使整個(gè)系統(tǒng)的運(yùn)行更協(xié)調(diào)。 對(duì)軟件進(jìn)一步的完善和細(xì)化,使系統(tǒng)的功能更穩(wěn)定、可靠。 完善系統(tǒng)的對(duì)外擴(kuò)展端口,增強(qiáng)系統(tǒng)的可擴(kuò)展性。 改善系統(tǒng)的硬件電路模塊的設(shè)計(jì)方式和換用功能強(qiáng)大的芯片,從而提高系統(tǒng)的實(shí)際功能,滿足更加復(fù)雜的工作條件的應(yīng)用。致謝這次畢業(yè)設(shè)計(jì)既是對(duì)大學(xué)所學(xué)知識(shí)的總結(jié)和運(yùn)用,更是一次創(chuàng)造性的實(shí)踐活動(dòng)。通過(guò)此次實(shí)踐學(xué)到了不少東西,歸納起來(lái),主要有以下六點(diǎn):大學(xué)不僅要學(xué)好專(zhuān)業(yè)理論基礎(chǔ)知識(shí),更要學(xué)以致用。由于我在平時(shí)的實(shí)驗(yàn)活動(dòng)中有意識(shí)的鍛煉和提高動(dòng)手能力,已經(jīng)掌握了一定的實(shí)踐能力,溝通能力也不錯(cuò)。但是經(jīng)過(guò)這次設(shè)計(jì),接觸了更多平時(shí)沒(méi)有接觸到的軟件、元器件及相關(guān)的調(diào)試經(jīng)驗(yàn),發(fā)現(xiàn)自己仍然有很多的不足之處。我還體會(huì)到了所學(xué)專(zhuān)業(yè)理論知識(shí)的重要性,所謂的博觀而約取,厚積而薄發(fā)正是這個(gè)道理,知識(shí)掌握得越多,設(shè)計(jì)得就更全面、更順利、更得心應(yīng)手。了解了進(jìn)行一項(xiàng)科技設(shè)計(jì)所必不可少的階段。畢業(yè)設(shè)計(jì)能夠從理論設(shè)計(jì)和工程實(shí)踐相結(jié)合、鞏固基礎(chǔ)知識(shí)與培養(yǎng)創(chuàng)新意識(shí)相結(jié)合、個(gè)人作用和集體協(xié)作相結(jié)合等方面培養(yǎng)學(xué)生的全面素質(zhì)。經(jīng)過(guò)這次系統(tǒng)的設(shè)計(jì),熟悉了一項(xiàng)課題進(jìn)行研究、設(shè)計(jì)和實(shí)驗(yàn)的詳細(xì)過(guò)程及和導(dǎo)師尋求必要幫助的溝通能力。這些能力將會(huì)在以后的工作和學(xué)習(xí)中發(fā)揮不可估量的作用。學(xué)會(huì)了如何搜集、歸納、分析所需資料和利用工具書(shū)。平時(shí)課堂上所學(xué)習(xí)的知識(shí)大多比較教條化,作為面向科技實(shí)踐的大學(xué)生,由于專(zhuān)業(yè)特點(diǎn)自己更要積極查閱當(dāng)前的最新科技資料。一個(gè)人不可能什么都學(xué)過(guò),什么都懂,因此,當(dāng)在設(shè)計(jì)過(guò)程中需要用到一些不曾接觸過(guò)的材料時(shí),就要有針對(duì)性、有目的的地查找資料,然后加以吸收利用,去粗取精,以提高自己的應(yīng)用能力,而且還能增長(zhǎng)自己的學(xué)識(shí),汲取到最新的專(zhuān)業(yè)知識(shí)。實(shí)踐能力得到了提高和在實(shí)踐過(guò)程中積累了一些經(jīng)驗(yàn)。設(shè)計(jì)過(guò)程是一個(gè)很復(fù)雜、很繁瑣的過(guò)程,這就需要在整個(gè)過(guò)程中目標(biāo)明確,有計(jì)劃性的開(kāi)展設(shè)計(jì)工作,特別是要有針對(duì)性的建立一個(gè)時(shí)間進(jìn)度表,來(lái)充分合理的利用有限的時(shí)間,以使設(shè)計(jì)達(dá)到預(yù)訂的效果;此外對(duì)軟硬件的再次運(yùn)用,更加深了對(duì)儀器儀表、開(kāi)發(fā)環(huán)境的認(rèn)識(shí),積累了良好的實(shí)踐經(jīng)驗(yàn)。畢業(yè)設(shè)計(jì)既對(duì)以前學(xué)過(guò)的理論知識(shí)起到了回顧作用,并對(duì)其加以進(jìn)一步的消化和鞏固,同時(shí)也對(duì)畢業(yè)以后所從事的實(shí)際工作有開(kāi)啟作用。畢業(yè)設(shè)計(jì)培養(yǎng)了嚴(yán)肅認(rèn)真和實(shí)事求是的科學(xué)態(tài)度。而且培養(yǎng)了吃苦耐勞、鍥而不舍的專(zhuān)研精神以及相對(duì)應(yīng)的團(tuán)隊(duì)意識(shí),同學(xué)之間的友誼和互助、導(dǎo)師展現(xiàn)的良師益友的品質(zhì)也充分的在此次畢業(yè)設(shè)計(jì)活動(dòng)當(dāng)中得到了體現(xiàn),而且也很好的教育了我。在此,大學(xué)生活即將結(jié)束之際,感謝母校對(duì)我四年的培養(yǎng),是她讓我成長(zhǎng)、學(xué)有所成;此外,誠(chéng)摯的感謝導(dǎo)師艾紅老師在整個(gè)設(shè)計(jì)過(guò)程中給予的細(xì)心指導(dǎo)和熱情幫助,還要真誠(chéng)地感謝在設(shè)計(jì)期間所有給我?guī)椭睦蠋熀屯瑢W(xué)。參考文獻(xiàn)1 ,智能家電及家居網(wǎng)絡(luò)[M].單片機(jī)與嵌入式系統(tǒng)應(yīng)用,2001: 22352 黃天戌,[J].電工技術(shù)雜志,:35373 何琳琳,[J].單片機(jī)開(kāi)發(fā)與應(yīng)用,:744 吳炳勝,王桂梅. 80C51單片機(jī)原理與應(yīng)用[M].冶金工業(yè)出版社,: 48535 ,:18-216 [J].(3):2922967 [M].中南大學(xué)出版社,2004,12:991308 [J].: 30359 曾剛,[M].電子技術(shù)應(yīng)用,10 8808 microprocessors, , Avter Singh, Prentice Hall,2001:7-8[J].浙江萬(wàn)里學(xué)院學(xué)報(bào),:123-12912李廣地,朱月秀,[M].北京航空航天大學(xué)出版社,:159-162[M].電子工業(yè)出版社,2002,514譚揚(yáng)波, for 15 ,:285-28816莫力. Protel ,17 Understanding Telephone Electronics, John. L. Fike, George E. Friend Texas Instruments Inc,2004:20-3518 Bushby S T. A standard munication infrastructure for intelligent Buildings. Automation in Construction [J]. : 52954019 Personal Computer XT/AT system Technical reference manual, Intel Corp.附錄APC REMOTE CONTROL OF APPLIANCES BY USING TELEPHONE LINESABSTRACTThe idea of Home Automation using telephone lines and a PC was shown in this study. The system was based on the Dual Tone Multifrequency (DTMF) signals that could be sent through a loop of wire to switch on/off various appliances via a Personal Computer (PC). The system hardware and software were designed based on the Telephone Standards. The hardware part included the DTMF receiver On/Off Hook detector, Ring detector and an Input/Output PC Interfacing card. An example of controlling an appliance was provided in the study. The software control programming was written in Turbo Basic and their flow charts are presented here for the reader39。s attention.INTRODUCTIONHome Automation that was introduced in this study was implemented by designing the Smart Control System that Controls All Appliances Remotely by Phone. The design was based on the Telephony Standards which meant that the system was qualified to be installed on the public switching systems. The system design was utilizing the Dual Tone Multifrequency (DTMF) signals that could be produced by the telephone set. These signals were sent from the user end through the loop wire to the destination end, where the control system was stationed. The system consisted of three major parts. The first part was the ring detector and DTMF receiver. The second part was the Input/Output interface unit. The third part was the personal puter which was programmed with Turbo Basic Software to perform the on line operations. Block diagram of the system was shown in figure 1.Figure1:Smart control system to control Appliances remotely by phoneBRIEF OPERATION OF A TELEPHONE SET:A summary of the telephone set operation was given here for the reader to visualize the system operation. Block diagram of a telephone set is shown in figure2.(a)Local loop: Each subscriber telephone was connected to an exchange office that contained the switching equipment, signalling equipment and batteries that supplied the direct current to operate the telephone. Each phone was connected to the central office through a local loop of two wires called a wire pair. One of the wires was called T (for tip) and the other one was called R (for ring) which referred to the TIP and RING parts of the switch used in manual switchboards. Switches in the exchange office responded to the dial pulses or tones from the telephone to connect the calling party to the called party. When the connection was established, the two telephones municated over transformer coupled loops using the current supplied by the exchange office batteries.(b) Initiating a call: The situation where the receiver handset was lifted from its cradle was called the offhook co