【正文】 第1718周，完善系統(tǒng)及論文。本階段應(yīng)該完成系統(tǒng)整體架構(gòu)設(shè)計(jì)和具體各個功能模塊的設(shè)計(jì)。二、目前已完成任務(wù)情況1. 電路圖已經(jīng)畫完，并且完成了Protues的仿真。1) 單片機(jī)的最小系統(tǒng)單片機(jī)最小系統(tǒng)包括外部晶振和復(fù)位電路。2. AD轉(zhuǎn)換模塊3. 使用ADC0808芯片，單片機(jī)P0口接受數(shù)據(jù)，P2口對其控制。3)顯示模塊本系統(tǒng)采用4個數(shù)碼管顯示數(shù)值。單片機(jī)P1口控制數(shù)碼管所顯示的數(shù)值，P3口以足夠高的速度對四個數(shù)碼管進(jìn)行掃描，并用三極管驅(qū)動數(shù)碼管發(fā)光。1) 蜂鳴報警模塊采用蜂鳴報警器，低電平有效；用P3^5控制蜂鳴報警。2) CO傳感器模塊由于Proteus軟件中沒有CO傳感器，所以采用滑動變阻器來改變AD輸入接口的電壓，使其能有高低電平的變換，從而模擬CO濃度正常與超限兩種情況；4. 程序部分：編寫了AD轉(zhuǎn)換函數(shù)、比較判斷函數(shù)(判斷結(jié)果存儲于特定數(shù)組)、蜂鳴報警函數(shù)、數(shù)碼管的顯示掃描函數(shù)、延時函數(shù)以及主函數(shù)。整體程序正在調(diào)試。三、存在的問題和擬解決方法1. 存在問題：蜂鳴函數(shù)調(diào)用問題。由于本系統(tǒng)為多路檢測、監(jiān)控系統(tǒng)，當(dāng)有某一分路超限而開始報警時，則即刻調(diào)用蜂鳴函數(shù)，開始蜂鳴報警。在該分路處于超限報警狀態(tài)時，有另一路開始報警，那么此時是再次調(diào)用蜂鳴函數(shù)，還是先判斷蜂鳴器是否已經(jīng)在報警，在報警則不再重復(fù)調(diào)用蜂鳴函數(shù)，否則調(diào)用蜂鳴函數(shù)。由于這兩種情況可能影響編程的效率以及實(shí)際應(yīng)用的效果，所以需要考慮；擬解決辦法：通過軟件模擬來檢測兩種不同情況的實(shí)際效果，或在焊接好實(shí)際電路板后在實(shí)驗(yàn)中檢測其效果(這兩種情況下使用的硬件電路是相同的)。2. 存在問題：程序還有幾個錯誤；擬解決辦法：查閱單片機(jī)編程書籍，用KeilC調(diào)試程序，排查程序中的各種錯誤。附錄4 燕 山 大 學(xué)本科畢業(yè)設(shè)計(jì)(論文)外文翻譯課題名稱：基于單片機(jī)的有毒氣體檢測系統(tǒng)的設(shè)計(jì) 學(xué)院(系)：電子工程系 年級專業(yè)： 08級通信工程2班 學(xué)生姓名： 袁博 指導(dǎo)教師： 盧輝斌 完成日期： 2012年3月31日 原文一：Carbon Monoxide DetectorsAccording to the Journal of the American Medical Association, carbon monoxide poisoning is the leading cause of accidental poisoning deaths in America. Carbon monoxide detectors are available, but you need to understand how they work and what their limitations are in order to decide whether or not you need a detector and, if you purchase a detector, how to use it to get the best protection.What is Carbon Monoxide?Carbon monoxide is an odorless, tasteless, invisible gas. Each carbon monoxide molecule is posed of a single carbon atom bonded to a single oxygen atom. Carbon monoxide results from the inplete bustion of fossil fuels, such as wood, kerosene, gasoline, charcoal, propane, natural gas, and oil.Where is Carbon Monoxide Found?Carbon monoxide is present in low levels in the air. In the home, it is formed from inplete bustion from any flamefueled (., not electric) device, including ranges, ovens, clothes dryers, furnaces, fireplaces, grills, space heaters, vehicles, and water heaters. Furnaces and water heaters may be sources of carbon monoxide, but if they are vented properly the carbon monoxide will escape to the outside. Open flames, such as from ovens and ranges, are the most mon source of carbon monoxide. Vehicles are the most mon cause of carbon monoxide poisoning.How Do Carbon Monoxide Detectors Work?Carbon monoxide detectors trigger an alarm based on an accumulation of carbon monoxide over time. Detectors may be based on a chemical reaction causing a color change, an electrochemical reaction that produces current to trigger an alarm, or a semiconductor sensor that changes its electrical resistance in the presence of CO. Most carbon monoxide detectors require a continuous power supply, so if the power cuts off then the alarm bees ineffective. Models are available that offer backup battery power. Carbon monoxide can harm you if you are exposed to high levels of carbon monoxide in a short period of time, or to lower levels of carbon monoxide over a long period of time, so there are different types of detectors depending on how the level of carbon monoxide is measured.Why is Carbon Monoxide Dangerous?When carbon monoxide is inhaled, it passes from the lungs into the hemoglobin molecules of red blood cells. Carbon monoxide binds to hemoglobin at the same site as and preferentially to oxygen, forming carboxyhemoglobin. Carboxyhemoglobin interferes with the oxygen transport and gas exchange abilities of red blood cells. The result is that the body bees oxygenstarved, which can result in tissue damage and death. Low levels of carbon monoxide poisoning cause symptoms similar to those of the flu or a cold, including shortness of breath on mild exertion, mild headaches, and nausea. Higher levels of poisoning lead to dizziness, mental confusion, severe headaches, nausea, and fainting on mild exertion. Ultimately, carbon monoxide poisoning can result in unconsciousness, permanent brain damage, and death. Carbon monoxide detectors are set to sound an alarm before the exposure to carbon monoxide would present a hazard to a healthy adult. Babies, children, pregnant women, people with circulatory or respiratory ailments, and the elderly are more sensitive to carbon monoxide than healthy adults.Where Should I Place a Carbon Monoxide Detector?Because carbon monoxide is slightly lighter than air and also because it may be found with warm, rising air, detectors should be placed on a wall about 5 feet above the floor. The detector may be placed on the ceiling. Do not place the detector right next to or over a fireplace or flameproducing appliance. Keep the detector out of the way of pets and children. Each floor needs a separate detector. If you are getting a single carbon monoxide detector, place it near the sleeping area and make certain the alarm is loud enough to wake you up.What Do I Do if the Alarm Sounds?Don39。t ignore the alarm! It is intended to go off before you are experiencing symptoms. Silence the alarm, get all members of the household to fresh air, and ask whether anyone is experiencing any of the symptoms of carbon monoxide poisoning. If anyone is experiencing symptoms of carbon monoxide poisoning, call 911. If no one has symptoms, ventilate the building, identify and remedy the source of the carbon monoxide before returning inside, and have appliances or chimneys checked by a professional as soon as possible.Additional Carbon Monoxide Concerns and InformationDon39。t automatically assume that you need or don39。t need a carbon monoxide detector. Also, don39。t assume that you are safe from carbon monoxide poisoning just because you have a detector installed. Carbon monoxide detectors are intended to protect healthy adults, so take the ages and health of family members into account when assessing the effectiveness of a detector. Also, be aware th