【正文】 ........ 4 設(shè)計方案 .............................................................................................................................. 4 工作原理 .............................................................................................................................. 6 第 3 章 系統(tǒng)的硬件設(shè)計 .................................................................................................................... 6 主控單元單片機(jī)的設(shè)計 ......................................................................................................... 6 單片機(jī)簡介 ................................................................................................................. 6 單片機(jī)的發(fā)展趨勢 ...................................................................................................... 7 單片機(jī) AT89S51 介紹 .................................................................................................. 8 AT89S51 的 I/O 口擴(kuò)展器件 ........................................................................................ 12 氣體采樣單元 ..................................................................................................................... 12 瓦斯氣體的介紹 ........................................................................................................ 12 氣體傳感器的分類 .................................................................................................... 13 氣體傳感器的選擇 .................................................................................................... 14 MQ4......................................................................................................................... 14 A/D 轉(zhuǎn)換單元 ...................................................................................................................... 18 A/D 轉(zhuǎn)換器的選型 ..................................................................................................... 19 ICL7109 芯片簡介 ...................................................................................................... 20 A/D 轉(zhuǎn)換部分電路 ..................................................................................................... 22 數(shù)據(jù)顯示單元 ..................................................................................................................... 24 II 顯示器的選擇 ........................................................................................................... 24 數(shù)據(jù)顯示部分電路 ..................................................................................................... 26 調(diào)節(jié)執(zhí)行單元 ..................................................................................................................... 29 電源單元 ............................................................................................................................ 30 報警單元 ............................................................................................................................ 31 第 4 章 系統(tǒng)的軟件設(shè)計 .................................................................................................................. 31 主程序 ............................................................................................................................... 31 子程序設(shè)計 ........................................................................................................................ 32 中斷子程序 ................................................................................................................ 32 聲光報警子程序 ........................................................................................................ 33 結(jié)論 ................................................................................................................................................ 33 參考文獻(xiàn) ......................................................................................................................................... 34 致謝 ................................................................................................................................................ 34 附錄 ................................................................................................................................................ 35 基于單片機(jī)的瓦斯監(jiān)控系統(tǒng)的硬件設(shè)計 摘要 本文概述了瓦斯監(jiān)控器的現(xiàn)狀及其基本原理，主要論述了利用單片機(jī)實現(xiàn)瓦斯監(jiān)控器的設(shè)計與實現(xiàn)方法。瓦斯監(jiān)控器是一種采用單片機(jī)控制的智能化儀表，為了滿足煤礦井下使用攜帶方便、安全可靠等要求，在設(shè)計上作了如下的必要的考慮 ： 考慮到小型化儀表的結(jié)構(gòu)，以及今后改進(jìn)的方便，我們將單片機(jī)進(jìn)行了模塊化處理。 本 文針對目前情況設(shè)計一種井下便攜式瓦斯監(jiān)控器， 以單片機(jī)為核心，氣敏傳感器把采集到的模擬量傳送給 A/D轉(zhuǎn)換器轉(zhuǎn)換成數(shù)字量交給單片機(jī)進(jìn)行處理， 當(dāng)瓦斯氣體濃度接近危險值時，自動發(fā)出報警，提醒井下人員立刻離開。 關(guān)鍵字： 單片機(jī) ， 瓦斯氣體檢測 ， 氣敏傳感器 ， 報警 ，實用 Hardware Design of Gas Monitoring System Based on MCU III Abstract This paper summarizes the present situation of gas monitors and its basic principle, mainly discusses the use of the single chip microputer to gas monitor methods of design and realization. Gas monitor is a kind of the single chip microputer control intelligent instruments, in order to satisfy the coal mine underground use is easy to carry, safety and reliability requirements, on the design made the following the necessary to consider: considering the miniaturization of instrument structure, as well as future improvement convenience, we will deal with the modular MCU. System modules are made by singlechip microputer control pleted. In view of present situation design a portable gas monitors, underground based on singlechip microputer is gas sensor, the acquisition of the analog transfer to the A/D converter converted into digital quantity to MCU processing, when gas concentration close to dangerous value, automatic alarm and remind miners to leave at once. The equipment and also with sensitivity adjustment and testing strength, switch to adjust simple, convenient and accurate, practical and so on the characteristic. Key words: MCU, Gas detection, gas sensor, alarm, practical 1 第 1 章 引言 課題背景 我國是煤炭生產(chǎn)大國，隨著煤礦機(jī)械化程度的提高，礦井生產(chǎn)能力和生產(chǎn)效率普 遍加大，煤炭年產(chǎn)量居世界首位，產(chǎn)煤量占世界總產(chǎn)煤量的 20%。 自 2020 年以來，隨著國家對煤礦企業(yè)安全生產(chǎn)要求的不斷提高和企業(yè)自身發(fā)展的需 要，我國各大、中、小