【正文】 ad poisoning accident. In some developed countries are heavily promoted even mandatory gas alarm, such as Tokyo and Osaka, Seoul, South Korea, Hamburg, Germany and other cities, there are more than 80% of the households to install all kinds of gas leakage detector based on singlechip microputer. Also, in some domestic cities such as Beijing, chengdu, Harbin and other cities, according to gas poisoning accidents occurred one after another, take decisive measures, in a couple of years ago, will be installed gas leakage alarm set forth in the form of local legislation, and the results of gas accidents declined dramatically. According to 1998 data show that every year only accident associated with liquefied petroleum gas (LPG) since 75, the city gas users happen accident rate is lower, and household gas alarm system development for 30 years in Japan, the Japanese government and enterprises to vigorously promote the use of alarm, leakage and explosion accidents of gas accident rate is far lower than Europe and the United States and other developed countries, gas leakage detector based on singlechip microputer has bee the necessities of family life. This topic design a gas leakage detector, monitor if there is a leak phenomenon kitchen burning gas, gas leak flow and according to the size, when the gas leakage value exceed safety standards, alarm system, gas according to whether there is abnormal phenomenon, and 基于單片機(jī)的燃?xì)庑孤稒z測(cè)儀設(shè)計(jì) IV the signal synchronization control solenoid valve to cut off the gas source. This design with low consumption of the microcontroller as the core device, the flow pulse signal input to MCU through gathering, through the software to determine whether or not in the range of reasonable flow, when the normal level, gives the corresponding control unit MCU control, alarm signal drive, the LCD shows the current accumulated flow rate at the same time and each focal switch state, at the same time, this design also will cooperate with DTU, serial port munication, far information module to PC for macro control, fundamentally solve the problem of safe use of gas, effectively avoid fire and explosion caused by gas leakage, asphyxia and death of malignant accidents. In order to achieve realtime monitoring the design adopts the double power supply, namely alternating power supply and battery power supply, and when the battery power is insufficient, this design can also under voltage alarm, when the city power supply this design will automatically jump to the battery power supply which is the design in the case of no electricity can also monitor. In addition, this design according to the national standard for antistatic, lightning protection, moistureproof, jitter considerations make this design to efficient and safe for consumer use. So this design has the following functions: Sampling function: ovens, gas flame thermocouple signal table output pulse signal, alarm signal. Alarm prompt: there are abnormal traffic, power supply voltage and the concentration of the alarm sound and light alarm information such as tips. Leakage detector power supply conversion function: the mains power supply can automatically switch to the standby power supply when mains power (battery) can automatically switch to city power supply when mains to restore state. Wireless munication function: being able to master station (concentrator) wireless munication function, can receive and reply to concentrator or a host of data acquisition and parameter setting mands. Key words: MCU。 電源轉(zhuǎn)換功能：采用市電供電的泄漏檢測(cè)儀在市電斷電時(shí)能自動(dòng)轉(zhuǎn)換到備用電源（內(nèi)部電池）當(dāng)市電恢復(fù)時(shí)能自動(dòng)轉(zhuǎn)換到城市供電狀態(tài)。 為了做到實(shí)時(shí)監(jiān)控本設(shè)計(jì)采用了雙電源供電，即電源與電池交替供電， 并且在當(dāng)電池電量不足時(shí)，本設(shè)計(jì)還能夠進(jìn)行欠壓報(bào)警， 當(dāng)城市停止供電時(shí)本設(shè)計(jì)會(huì)自動(dòng)跳轉(zhuǎn)到電池供電從而是本設(shè)計(jì)在沒(méi)電的情況下也能進(jìn)行監(jiān)控。 據(jù) 1998 年資料顯示，每年與液化石油氣有 關(guān)的事故僅發(fā)生 75 起，而城市燃?xì)夤艿烙脩舭l(fā)生事故率更低，家用燃?xì)鈭?bào)警器在日本發(fā)展 30 年來(lái) , 日本政府和生產(chǎn)企業(yè)大力推廣報(bào)警器的使用，使燃?xì)庑孤┖捅ǖ仁鹿实氖鹿事蔬h(yuǎn)遠(yuǎn)低于歐美等發(fā)達(dá)國(guó)家，基于單片機(jī)的燃?xì)庑孤z測(cè)儀已成為家庭生活的必需品 。能有效避免因燃?xì)庑孤抖鸬谋?、火?zāi)、中毒等惡性事故發(fā)生，在全世界大部分國(guó)家地區(qū)廣泛應(yīng)用。華北科技學(xué)院畢業(yè)設(shè)計(jì)（論文） 目錄 設(shè)計(jì)總說(shuō)明 ........................................................... I Introduction ......................................................... III 1 緒論 ............................................................... 1 課題背景及研究意義 .............................................. 1 主要研究?jī)?nèi)容及結(jié)構(gòu)安排 .......................................... 1 2 燃?xì)庑孤z測(cè)儀系統(tǒng)構(gòu)成框圖 ......................................... 3 系統(tǒng)構(gòu)成框圖 .................................................... 3 系統(tǒng)構(gòu)成方案及論證 ......................................... 3 系統(tǒng)構(gòu)成框圖 ............................................... 4 3 燃?xì)庑孤z測(cè)儀硬件設(shè)計(jì) ............................................. 5 MCU 核心模塊設(shè)計(jì) ................................................ 5 MSP430 系列單片機(jī)發(fā)展歷程 ................................... 5 MSP430 系列單片機(jī)的應(yīng)用領(lǐng)域 ................................. 5 單片機(jī)最小系統(tǒng)介紹 ......................................... 6 單片機(jī)的選型 ............................................... 9 單片機(jī)外圍電路設(shè)計(jì) ........................................ 11 采集模塊硬件設(shè)計(jì) ............................................... 11 串口模塊硬件設(shè)計(jì) ............................................... 13 雙電源供電模塊硬件設(shè)計(jì) ......................................... 15 雙 12V 穩(wěn)壓電源設(shè)計(jì) ........................................ 15 電源設(shè)計(jì) .............................................. 16 LCD 液晶顯示模塊設(shè)計(jì) ........................................... 18 本章小結(jié) ....................................................... 21 4 燃?xì)庑孤z測(cè)儀軟件設(shè)計(jì)與實(shí)現(xiàn) ...................................... 22 總程序流程圖 ................................................... 22 顯示模塊軟件設(shè)計(jì) ............................................... 22 基于單片機(jī)的燃?xì)庑孤稒z測(cè)儀設(shè)計(jì) 顯示模塊軟件調(diào)試 ............................................... 28 本章小結(jié) ....................................................... 29 5 硬件的安裝與調(diào)試 .................................................. 30 PCB 版的設(shè)計(jì) ................................................... 30 PCB 板的調(diào)試 ......................................