【正文】 初始化后，經(jīng)外圍設(shè)備，通過A/D轉(zhuǎn)換器，將信號轉(zhuǎn)換后進行讀取，當IC卡中的金額不足或沒有時，將顯示出來并報警響鈴，同時關(guān)閉電磁閥，續(xù)費后，電磁閥開啟，功能正常。 顯示子程序顯示子程序在整個系統(tǒng)中被頻繁調(diào)用，用來顯示燃氣表的實際工作情況，實施設(shè)備與用戶最直觀、最簡潔的連接橋梁。在本設(shè)計中，燃氣表正常工作時，顯示剩余燃氣量。當電池電量不足時顯示“電量不足”；當燃氣量不足10方且大于0方時顯示“燃氣已用完”；當氣量不足0方時顯示人“燃氣已用完”。 主程序流程圖 IC卡讀寫程序 IC卡檢測流程采用了智能化的設(shè)計，首先檢測是否有IC卡插入，在檢測有正確IC卡存在的前提下，對IC卡密碼進行核對，讀取IC卡存儲內(nèi)容后，進行相應(yīng)的處理，插卡中斷子程序主要是當單片機處于休眠狀態(tài)時，有卡插入激活單片機，從而對卡進行讀卡操作，并顯示讀卡結(jié)果。 當用戶沒有用氣時，單片機處于休眠狀態(tài)，用氣中斷是指，用戶開氣閥用氣時，激活單片機，開始正常工作，然后顯示其剩余氣量從而完成用氣操作。本設(shè)計采用單片機AT89S52內(nèi)含看門狗功能，看門狗電路就是一個定時激活電路，其作用是防止單片機進入死循環(huán)，監(jiān)控程序的正常工作。在程序正常執(zhí)行一遍后，會清零到看門狗計數(shù)器，所以不會到達最大計數(shù)值，但是如果外部干擾引起死循環(huán)，定時器達到最大計數(shù)值時就會自動復位單片機，從而防止單片機進入死循環(huán)。 氣量處理是指當燃氣表正常工作時通過對總氣量的處理顯示剩余氣量，當插入卡時通過讀入卡內(nèi)氣量值與剩余氣量相加得到新的總氣量，同時將卡內(nèi)的數(shù)值清零。 定時中斷 定時中斷程序流程圖當燃氣表電量不足時顯示“電量不足”,當電池電量不足以供單片機正常工作時，要對當前的數(shù)據(jù)量進行保存，以保證數(shù)據(jù)不會丟失。 氣量處理程序流程圖當單片機處于休眠狀態(tài)時，延時十秒檢測有無中斷信號打破休眠狀態(tài)，進入正常運行狀態(tài)。 延時子程序流程圖當用戶開閥用氣時，就有信號輸入單片機，通過計量信號，計算燃氣剩余量，從而實現(xiàn)氣量計算。 第5章 總結(jié)本設(shè)計主要闡述了IC卡燃氣表的硬件、軟件設(shè)計方案，包括系統(tǒng)功能，工作原理、結(jié)構(gòu)框圖、硬件各部分電路設(shè)計及其軟件程序編寫等。涉及領(lǐng)域包括電子、單片機、匯編語言等多門學科。在本系統(tǒng)的設(shè)計過程中，硬件方面的重點是燃氣表測量電路、控制電路等的設(shè)計。軟件部分來用AT89C51單片機的匯編語言編寫，設(shè)計中應(yīng)用模塊化設(shè)計結(jié)構(gòu)，完成了電表的計費功能。參考文獻[l]周曉中，杜偉，2006，27(l):84～86[2][M].重慶:重慶出版社，～30[3][J]，1999，19(3):48～50[4][J]，1994(6):12～16[5]:清華大學出版社，1996.[6](IC)卡規(guī)范砰().北京:中國金融出版社，1998[7][J]，1998，12(4):32～39[8][J]，1996(2):7～9[9]:握奇智能科技有限公司，2002(l):4[l0][J]，2007，383(l):20～22[l1]陳伯揚，2008，22(2):41～43[l2]，2004，8(1):54～56[13][J]，2000,(l):21～22[l4][J]，2004，18(6):26～28[l5][M].機械工業(yè)出版社，2005.[16] Gas Research Institute ,Gas metersSmaller, Betterlooking and Smarter, GRI Report ,Technology Focus,Chicago,1992.中英文翻譯 From the world of radio in the world to a single chipModern puter technology, industrial revolution, the world economy from the capital into the economy to knowledge economy. Field in the electronic world, from the 20th century into the era of radio to puter technology in the 21st century as the center of the intelligent modern era of electronic systems. The basic core of modern electronic systems are embedded puter systems (referred to as embedded systems), while the microcontroller is the most typical and most extensive and most popular embedded systems.First, radio has created generations of excellence in the worldFifties and sixties in the 20th century, the most representative of the advanced electronic technology is wireless technology, including radio broadcasting, radio, wireless munications (telegraph), Amateur Radio, radio positioning, navigation and other telemetry, remote control, remote technology. Early that these electronic technology led many young people into the wonderful digital world, radio show was a wonderful life, the prospects for science and technology. Electronics began to form a new discipline. Radio electronics, wireless munications began eworld journey.Radio technology not only as a representative of advanced science and technology at that time, but also from popular to professional fields of science, attracting the young people and enable them to find a lot of fun. Ore from the bedside to the superheterodyne radio radio。 report issued from the radio amateur radio stations。 from the telephone, electric bell to the radio control model. Became popular youth radio technology, science and technology education is the most popular and most extensive content. So far, many of the older generation of engineers, experts, Professor of the year are radio enthusiasts. Fun radio technology, radio technology, prehensive training, from basic principles of electronics, electronic ponents to the radiobased remote control, telemetry, remote electronic systems, has trained several generations of technological excellence.Second, from the popularity of the radio era to era of electronic technology The early radio technology to promote the development of electronic technology, most notably electronic vacuum tube technology to semiconductor electronic technology. Semiconductor technology to realize the active device miniaturization and low cost, so more popular with radio technology and innovation, and to greatly broaden the number of nonradiocontrol areas. The development of semiconductor technology lead to the production of integrated circuit, forming the modern electronic technology leap from discrete electronics into the era of era of integrated circuits. Electronic design engineers no longer use the discrete electronic ponents designed circuit modules, and direct selection of integrated circuit ponents constitute a single system. They freed the design of the circuit unit dedicated to system design, greatly liberating the productive forces of science and technology, promote the wider spread of electronic systems. Semiconductor integrated circuits in the basic digital logic circuits first breakthrough. A large number of digital logic circuits, such as gates, counters, timers, shift registers, and analog switches, parators, etc., for the electronic digital control provides excellent conditions for the traditional mechanical control to electronic control. Power electronic devices and sensor technology to make the original to the radio as the center of electronic technology turned to mechanical engineering in the field of digital control systems, testing in the field of information collection, movement of electrical mechanical servo drive control object. Semiconductor and integrated circuit technology will bring us a universal age of electronic technology, wireless technology as the field of electronic technology a part of. 70 years into the 20th century, large scale integrated circuit appeared to promote the conventional electronic circuit unitspecific electronic systems development. Many electronic systems unit into a dedicated integrated devices such as radios, el