查看“Micro:bit系列教程18：Flame Sensor”的源代码

<p class="MsoNormal" style="line-height:150%"><span style="font-size:12.0pt;
line-height:150%;font-family:宋体">本章将介绍<span lang="EN-US">Flame Sensor(火焰传感器</span>)对火焰的检测。<span lang="EN-US"></span></span></p>
<h1><span lang="EN-US" style="font-size:15.0pt;line-height:240%;font-family:黑体">1.</span><span style="font-size:15.0pt;line-height:240%;font-family:黑体">基本介绍<span lang="EN-US"></span></span></h1>
<p class="MsoNormal" style="line-height:150%"><span lang="EN-US" style="font-size:
12.0pt;line-height:150%;font-family:宋体"><span style="mso-tab-count:1">  </span>Flame
Sensor</span><span style="font-size:12.0pt;line-height:150%;font-family:宋体">模块可对火焰进行感知，其中，对火焰敏感的二极管被火焰照射后，电阻发生变化，进而导致二极管两端的电压发生变化，产生模拟信号，同时，该模拟信号经过电压比较器的处理，当模拟信号超过一定门限值的时候，做出相应的报警。<span lang="EN-US"></span></span></p>
<h1><span lang="EN-US" style="font-size:15.0pt;line-height:240%;font-family:黑体">2.</span><span style="font-size:15.0pt;line-height:240%;font-family:黑体">硬件连接<span lang="EN-US"></span></span></h1>
<p class="MsoNormal" style="line-height:150%"><span lang="EN-US" style="font-size:
18.0pt;line-height:150%;font-family:黑体"><span style="mso-tab-count:1"> </span></span><span style="font-size:12.0pt;line-height:150%;font-family:宋体">在硬件上，采用<span lang="EN-US">Micro:bit</span>的<span lang="EN-US">P0</span>引脚来采集模拟电压。并进行<span lang="EN-US">AD</span>转换，从而得到数字信号，采用<span lang="EN-US">Micro:bit</span>的<span lang="EN-US">P1</span>引脚连接<span lang="EN-US">Flame Sensor</span>的数字输出来判断是否靠近火焰。<span lang="EN-US"></span></span></p>
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<p align="center" class="MsoNormal" style="text-align:center;line-height:150%"><span lang="EN-US" style="font-size:12.0pt;line-height:150%;font-family:宋体">Micro:bit</span></p>
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<p align="center" class="MsoNormal" style="text-align:center;line-height:150%"><span lang="EN-US" style="font-size:12.0pt;line-height:150%;font-family:宋体">Flame Sensor</span></p>
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<p align="center" class="MsoNormal" style="text-align:center;line-height:150%"><span lang="EN-US" style="font-size:12.0pt;line-height:150%;font-family:宋体">VCC</span></p>
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<p align="center" class="MsoNormal" style="text-align:center;line-height:150%"><span lang="EN-US" style="font-size:12.0pt;line-height:150%;font-family:宋体">GND</span></p>
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<p align="center" class="MsoNormal" style="text-align:center;line-height:150%"><span lang="EN-US" style="font-size:12.0pt;line-height:150%;font-family:宋体">GND</span></p>
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<p align="center" class="MsoNormal" style="text-align:center;line-height:150%"><span lang="EN-US" style="font-size:12.0pt;line-height:150%;font-family:宋体">P0</span></p>
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<p align="center" class="MsoNormal" style="text-align:center;line-height:150%"><span lang="EN-US" style="font-size:12.0pt;line-height:150%;font-family:宋体">AOUT</span></p>
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<p align="center" class="MsoNormal" style="text-align:center;line-height:150%"><span lang="EN-US" style="font-size:12.0pt;line-height:150%;font-family:宋体">P1</span></p>
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<p align="center" class="MsoNormal" style="text-align:center;line-height:150%"><span lang="EN-US" style="font-size:12.0pt;line-height:150%;font-family:宋体">DOUT</span></p>
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<p class="MsoNormal" style="line-height:150%"><span style="font-size:12.0pt;
line-height:150%;font-family:宋体">具体硬件连接如下图所示：<span lang="EN-US"></span></span></p>
<p>[[File:Micro：bit系列教程18：Flame_Sensor感知火焰-0.png|400px]]</p>
<p class="MsoNormal" style="line-height:150%;mso-pagination:widow-orphan"><span lang="EN-US" style="font-size:15.0pt;line-height:150%;font-family:黑体">3.</span><span style="font-size:15.0pt;line-height:150%;font-family:黑体">软件设计<span lang="EN-US"></span></span></p>
<p class="MsoNormal" style="line-height:150%;mso-pagination:widow-orphan"><span lang="EN-US" style="font-size:15.0pt;line-height:150%;font-family:黑体"><span style="mso-tab-count:1">  </span></span><span style="font-size:12.0pt;
line-height:150%;font-family:宋体">打开<span lang="EN-US">makecode</span>，添加软件包，输入以下链接：<span lang="EN-US"></span></span></p>
<p class="MsoNormal" style="line-height:150%;mso-pagination:widow-orphan"><span lang="EN-US"><span style="font-size:12.0pt;line-height:150%;font-family:宋体">https://github.com/waveshare/CourseKit</span></span><span class="MsoHyperlink"><span lang="EN-US" style="font-size:12.0pt;line-height:150%;
font-family:宋体"></span></span></p>
<p class="MsoNormal" style="line-height:150%;mso-pagination:widow-orphan"><span style="font-size:12.0pt;line-height:150%;font-family:宋体">添加软件包成功后，采用积木块编写以下程序：<span lang="EN-US"></span></span></p>
<p>[[File:Micro：bit系列教程18：Flame_Sensor感知火焰-1.png|400px]]</p>
<p class="MsoNormal" style="line-height:150%;mso-pagination:widow-orphan"><span style="font-size:12.0pt;line-height:150%;font-family:宋体">点击显示数据<span lang="EN-US">(</span>设备<span lang="EN-US">)</span>按钮，将显示采集到<span lang="EN-US">Flame Sensor</span>的原始<span lang="EN-US">ADC</span>值，转换后的电压，以及是否靠近火焰等，具体数据如下图所示：<span lang="EN-US"></span></span></p>
<p>[[File:Micro：bit系列教程18：Flame_Sensor感知火焰-2.png|400px]]</p>
<p class="MsoNormal" style="line-height:150%;mso-pagination:widow-orphan"><span style="font-size:12.0pt;line-height:150%;font-family:宋体">当模块靠近火焰时，模块上的信号指示灯点亮；当模块远离火焰时，模块上的信号指示灯熄灭。随着模块与火焰距离的变化，串口输出的<span lang="EN-US">ADC</span>值和转换后的电压值均会发生相应的变化。<span lang="EN-US"></span></span></p>