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  <author>
    <name>泠@RinOo</name>
  </author>
  <generator uri="https://hexo.io/">Hexo</generator>
  <id>https://rin3water.pages.dev/</id>
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  <rights>All rights reserved 2026, 泠@RinOo</rights>
  <subtitle>电子信息工程 · 学习记录</subtitle>
  <title>泠RinOo的博客</title>
  <updated>2026-09-25T10:37:50.946Z</updated>
  <entry>
    <author>
      <name>泠@RinOo</name>
    </author>
    <category term="站务" scheme="https://rin3water.pages.dev/categories/%E7%AB%99%E5%8A%A1/"/>
    <category term="博客" scheme="https://rin3water.pages.dev/tags/%E5%8D%9A%E5%AE%A2/"/>
    <category term="使用说明" scheme="https://rin3water.pages.dev/tags/%E4%BD%BF%E7%94%A8%E8%AF%B4%E6%98%8E/"/>
    <category term="Markdown" scheme="https://rin3water.pages.dev/tags/Markdown/"/>
    <content>
      <![CDATA[<p>博客搭好了。与其写一篇 &quot;Hello World&quot;，不如把这篇当成我自己的使用说明书 —— 以后忘了怎么写公式、怎么放图片，翻回来看这篇就行。</p><span id="more"></span><h2 id="一、这个博客写什么">一、这个博客写什么</h2><p>作为电子信息工程的学生，我打算主要记四类内容：</p><table><thead><tr><th>类型</th><th>具体内容</th><th>为什么值得写</th></tr></thead><tbody><tr><td>课程笔记</td><td>高数、线代、信号与系统、模电、数电</td><td>期末复习直接用，比抄一遍笔记效率高</td></tr><tr><td>实验记录</td><td>示波器、Multisim、Keil、STM32</td><td>踩过的坑下次不用再踩</td></tr><tr><td>项目日志</td><td>电赛、大创、单片机项目</td><td>面试时能讲出细节</td></tr><tr><td>复盘总结</td><td>失败原因、低效的原因</td><td>最值钱，但最难坚持</td></tr></tbody></table><h2 id="二、怎么发下一篇">二、怎么发下一篇</h2><p>在博客根目录打开终端（VS Code 菜单：<strong>终端 → 新建终端</strong>），运行：</p><figure class="highlight bash"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><code class="hljs bash">npx hexo new <span class="hljs-string">&quot;文章标题&quot;</span><br></code></pre></td></tr></table></figure><p>Hexo 会在 <code>source/_posts/</code> 下生成一个 Markdown 文件，还会自动建一个同名文件夹专门放这篇文章的图片。</p><p>写完保存，本地预览：</p><figure class="highlight bash"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><code class="hljs bash">npx hexo server<br></code></pre></td></tr></table></figure><p>浏览器打开 <a href="http://localhost:4000">http://localhost:4000</a> 就能看到效果。确认没问题后提交到 GitHub，Cloudflare Pages 会自动重新构建（大约 1 分钟）。</p><h2 id="三、常用语法速查">三、常用语法速查</h2><h3 id="数学公式">数学公式</h3><p>行内公式用单个美元符号，比如一阶 RC 低通滤波器的截止频率 <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><msub><mi>f</mi><mi>c</mi></msub><mo>=</mo><mstyle scriptlevel="0" displaystyle="true"><mfrac><mn>1</mn><mrow><mn>2</mn><mi>π</mi><mi>R</mi><mi>C</mi></mrow></mfrac></mstyle></mrow><annotation encoding="application/x-tex">f_c = \dfrac{1}{2\pi RC}</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="katex-base"><span class="katex-strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord"><span class="mord mathnormal" style="margin-right:0.1076em;">f</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:-0.1076em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="katex-sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">c</span></span></span></span><span class="vlist-s">​</span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="katex-base"><span class="katex-strut" style="height:2.0074em;vertical-align:-0.686em;"></span><span class="mord"><span class="mopen nulldelimiter"></span><span class="mfrac"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:1.3214em;"><span style="top:-2.314em;"><span class="pstrut" style="height:3em;"></span><span class="mord"><span class="mord">2</span><span class="mord mathnormal" style="margin-right:0.0359em;">π</span><span class="mord mathnormal" style="margin-right:0.0077em;">R</span><span class="mord mathnormal" style="margin-right:0.0715em;">C</span></span></span><span style="top:-3.23em;"><span class="pstrut" style="height:3em;"></span><span class="frac-line" style="border-bottom-width:0.04em;"></span></span><span style="top:-3.677em;"><span class="pstrut" style="height:3em;"></span><span class="mord"><span class="mord">1</span></span></span></span><span class="vlist-s">​</span></span><span class="vlist-r"><span class="vlist" style="height:0.686em;"><span></span></span></span></span></span><span class="mclose nulldelimiter"></span></span></span></span></span>。</p><p>独立成行的公式用两个美元符号：</p><p><span class="katex-display"><span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML" display="block"><semantics><mrow><mi>H</mi><mo stretchy="false">(</mo><mi>j</mi><mi>ω</mi><mo stretchy="false">)</mo><mo>=</mo><mfrac><mn>1</mn><mrow><mn>1</mn><mo>+</mo><mi>j</mi><mi>ω</mi><mi>R</mi><mi>C</mi></mrow></mfrac><mo separator="true">,</mo><mspace width="2em"/><mi mathvariant="normal">∣</mi><mi>H</mi><mo stretchy="false">(</mo><mi>j</mi><mi>ω</mi><mo stretchy="false">)</mo><mi mathvariant="normal">∣</mi><mo>=</mo><mfrac><mn>1</mn><msqrt><mrow><mn>1</mn><mo>+</mo><mo stretchy="false">(</mo><mi>ω</mi><mi>R</mi><mi>C</mi><msup><mo stretchy="false">)</mo><mn>2</mn></msup></mrow></msqrt></mfrac></mrow><annotation encoding="application/x-tex">H(j\omega) = \frac{1}{1 + j\omega RC},\qquad|H(j\omega)| = \frac{1}{\sqrt{1 + (\omega RC)^2}}</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="katex-base"><span class="katex-strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal" style="margin-right:0.0813em;">H</span><span class="mopen">(</span><span class="mord mathnormal" style="margin-right:0.0572em;">j</span><span class="mord mathnormal" style="margin-right:0.0359em;">ω</span><span class="mclose">)</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="katex-base"><span class="katex-strut" style="height:2.2019em;vertical-align:-0.8804em;"></span><span class="mord"><span class="mopen nulldelimiter"></span><span class="mfrac"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:1.3214em;"><span style="top:-2.314em;"><span class="pstrut" style="height:3em;"></span><span class="mord"><span class="mord">1</span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mord mathnormal" style="margin-right:0.0572em;">j</span><span class="mord mathnormal" style="margin-right:0.0359em;">ω</span><span class="mord mathnormal" style="margin-right:0.0077em;">R</span><span class="mord mathnormal" style="margin-right:0.0715em;">C</span></span></span><span style="top:-3.23em;"><span class="pstrut" style="height:3em;"></span><span class="frac-line" style="border-bottom-width:0.04em;"></span></span><span style="top:-3.677em;"><span class="pstrut" style="height:3em;"></span><span class="mord"><span class="mord">1</span></span></span></span><span class="vlist-s">​</span></span><span class="vlist-r"><span class="vlist" style="height:0.8804em;"><span></span></span></span></span></span><span class="mclose nulldelimiter"></span></span><span class="mpunct">,</span><span class="mspace" style="margin-right:2em;"></span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord">∣</span><span class="mord mathnormal" style="margin-right:0.0813em;">H</span><span class="mopen">(</span><span class="mord mathnormal" style="margin-right:0.0572em;">j</span><span class="mord mathnormal" style="margin-right:0.0359em;">ω</span><span class="mclose">)</span><span class="mord">∣</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="katex-base"><span class="katex-strut" style="height:2.4514em;vertical-align:-1.13em;"></span><span class="mord"><span class="mopen nulldelimiter"></span><span class="mfrac"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:1.3214em;"><span style="top:-2.175em;"><span class="pstrut" style="height:3em;"></span><span class="mord"><span class="mord sqrt"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.935em;"><span class="svg-align" style="top:-3.2em;"><span class="pstrut" style="height:3.2em;"></span><span class="mord" style="padding-left:1em;"><span class="mord">1</span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222em;"></span><span class="mopen">(</span><span class="mord mathnormal" style="margin-right:0.0359em;">ω</span><span class="mord mathnormal" style="margin-right:0.0077em;">R</span><span class="mord mathnormal" style="margin-right:0.0715em;">C</span><span class="mclose"><span class="mclose">)</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.7401em;"><span style="top:-2.989em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="katex-sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span></span></span></span></span></span></span><span style="top:-2.895em;"><span class="pstrut" style="height:3.2em;"></span><span class="hide-tail" style="min-width:1.02em;height:1.28em;"><svg xmlns="http://www.w3.org/2000/svg" width="400em" height="1.28em" viewBox="0 0 400000 1296" preserveAspectRatio="xMinYMin slice"><path d="M263,681c0.7,0,18,39.7,52,119c34,79.3,68.167,158.7,102.5,238c34.3,79.3,51.8,119.3,52.5,120c340,-704.7,510.7,-1060.3,512,-1067l0 -0c4.7,-7.3,11,-11,19,-11H40000v40H1012.3s-271.3,567,-271.3,567c-38.7,80.7,-84,175,-136,283c-52,108,-89.167,185.3,-111.5,232c-22.3,46.7,-33.8,70.3,-34.5,71c-4.7,4.7,-12.3,7,-23,7s-12,-1,-12,-1s-109,-253,-109,-253c-72.7,-168,-109.3,-252,-110,-252c-10.7,8,-22,16.7,-34,26c-22,17.3,-33.3,26,-34,26s-26,-26,-26,-26s76,-59,76,-59s76,-60,76,-60zM1001 80h400000v40h-400000z"/></svg></span></span></span><span class="vlist-s">​</span></span><span class="vlist-r"><span class="vlist" style="height:0.305em;"><span></span></span></span></span></span></span></span><span style="top:-3.23em;"><span class="pstrut" style="height:3em;"></span><span class="frac-line" style="border-bottom-width:0.04em;"></span></span><span style="top:-3.677em;"><span class="pstrut" style="height:3em;"></span><span class="mord"><span class="mord">1</span></span></span></span><span class="vlist-s">​</span></span><span class="vlist-r"><span class="vlist" style="height:1.13em;"><span></span></span></span></span></span><span class="mclose nulldelimiter"></span></span></span></span></span></span></p><p>傅里叶变换这种也没问题：</p><p><span class="katex-display"><span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML" display="block"><semantics><mrow><mi>X</mi><mo stretchy="false">(</mo><mi>j</mi><mi>ω</mi><mo stretchy="false">)</mo><mo>=</mo><msubsup><mo>∫</mo><mrow><mo>−</mo><mi mathvariant="normal">∞</mi></mrow><mrow><mo>+</mo><mi mathvariant="normal">∞</mi></mrow></msubsup><mi>x</mi><mo stretchy="false">(</mo><mi>t</mi><mo stretchy="false">)</mo><mtext> </mtext><msup><mi>e</mi><mrow><mo>−</mo><mi>j</mi><mi>ω</mi><mi>t</mi></mrow></msup><mtext> </mtext><mi>d</mi><mi>t</mi></mrow><annotation encoding="application/x-tex">X(j\omega) = \int_{-\infty}^{+\infty} x(t)\, e^{-j\omega t} \, dt</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="katex-base"><span class="katex-strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal" style="margin-right:0.0785em;">X</span><span class="mopen">(</span><span class="mord mathnormal" style="margin-right:0.0572em;">j</span><span class="mord mathnormal" style="margin-right:0.0359em;">ω</span><span class="mclose">)</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="katex-base"><span class="katex-strut" style="height:2.4915em;vertical-align:-0.9703em;"></span><span class="mop"><span class="mop op-symbol large-op" style="margin-right:0.4445em;position:relative;top:-0.0011em;">∫</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:1.5212em;"><span style="top:-1.7881em;margin-left:-0.4445em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="katex-sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">−</span><span class="mord mtight">∞</span></span></span></span><span style="top:-3.8129em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="katex-sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">+</span><span class="mord mtight">∞</span></span></span></span></span><span class="vlist-s">​</span></span><span class="vlist-r"><span class="vlist" style="height:0.9703em;"><span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">x</span><span class="mopen">(</span><span class="mord mathnormal">t</span><span class="mclose">)</span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord"><span class="mord mathnormal">e</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8747em;"><span style="top:-3.113em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="katex-sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">−</span><span class="mord mathnormal mtight" style="margin-right:0.0572em;">j</span><span class="mord mathnormal mtight" style="margin-right:0.0359em;">ω</span><span class="mord mathnormal mtight">t</span></span></span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">d</span><span class="mord mathnormal">t</span></span></span></span></span></p><blockquote><p>公式是<strong>构建时</strong>用 KaTeX 渲染成 HTML 的，不依赖外部 CDN，所以没网也能正常显示。</p></blockquote><h3 id="代码">代码</h3><p>标注语言就会自动高亮：</p><figure class="highlight c"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br></pre></td><td class="code"><pre><code class="hljs c"><span class="hljs-comment">// STM32 点灯：让 PA5 输出高电平</span><br><span class="hljs-meta">#<span class="hljs-keyword">include</span> <span class="hljs-string">&quot;stm32f10x.h&quot;</span></span><br><br><span class="hljs-type">int</span> <span class="hljs-title function_">main</span><span class="hljs-params">(<span class="hljs-type">void</span>)</span> &#123;<br>    RCC-&gt;APB2ENR |= RCC_APB2ENR_IOPAEN;   <span class="hljs-comment">// 使能 GPIOA 时钟</span><br>    GPIOA-&gt;CRL &amp;= ~(<span class="hljs-number">0xF</span> &lt;&lt; <span class="hljs-number">20</span>);           <span class="hljs-comment">// 清空 PA5 的配置位</span><br>    GPIOA-&gt;CRL |=  (<span class="hljs-number">0x3</span> &lt;&lt; <span class="hljs-number">20</span>);           <span class="hljs-comment">// 推挽输出，50MHz</span><br>    <span class="hljs-keyword">while</span> (<span class="hljs-number">1</span>) &#123;<br>        GPIOA-&gt;BSRR = GPIO_BSRR_BS5;      <span class="hljs-comment">// PA5 = 1</span><br>    &#125;<br>&#125;<br></code></pre></td></tr></table></figure><p>Python 也一样：</p><figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br></pre></td><td class="code"><pre><code class="hljs python"><span class="hljs-keyword">import</span> numpy <span class="hljs-keyword">as</span> np<br><span class="hljs-keyword">import</span> matplotlib.pyplot <span class="hljs-keyword">as</span> plt<br><br>fs, T = <span class="hljs-number">1000</span>, <span class="hljs-number">0.1</span><br>t = np.arange(<span class="hljs-number">0</span>, T, <span class="hljs-number">1</span> / fs)<br>x = np.sin(<span class="hljs-number">2</span> * np.pi * <span class="hljs-number">50</span> * t) + <span class="hljs-number">0.3</span> * np.random.randn(<span class="hljs-built_in">len</span>(t))<br><br>plt.plot(t, x)<br>plt.xlabel(<span class="hljs-string">&quot;t / s&quot;</span>)<br>plt.show()<br></code></pre></td></tr></table></figure><h3 id="图片">图片</h3><p>图片放在<strong>文章同名文件夹</strong>里，正文直接写文件名：</p><figure class="highlight bash"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><code class="hljs bash"><span class="hljs-built_in">source</span>/_posts/<br>├── hello-world.md<br>└── hello-world/<br>    └── 波形图.png        ← 图片放这里<br></code></pre></td></tr></table></figure><p>然后在正文里：</p><figure class="highlight markdown"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><code class="hljs markdown">![<span class="hljs-string">示波器波形</span>](<span class="hljs-link">波形图.png</span>)<br></code></pre></td></tr></table></figure><p>这样图片跟着文章走，以后迁移博客不会丢。</p><h3 id="其他常用写法">其他常用写法</h3><ul><li><strong>加粗</strong>、<em>斜体</em>、<s>删除线</s>、<mark>文字高亮</mark></li><li>下标 H<sub>2</sub>O，上标 x<sup>2</sup></li><li>行内代码用反引号包起来，比如 <code>GPIOA-&gt;BSRR</code></li><li>引用：</li></ul><blockquote><p>记录的意义不在于好看，而在于半年后你还能看懂自己当时在想什么。</p></blockquote><p>任务列表（记项目进度很顺手）：</p><ul class="contains-task-list"><li class="task-list-item"><input class="task-list-item-checkbox" checked="" disabled="" type="checkbox"> 把博客搭起来</li><li class="task-list-item"><input class="task-list-item-checkbox" disabled="" type="checkbox"> 写满 10 篇文章</li><li class="task-list-item"><input class="task-list-item-checkbox" disabled="" type="checkbox"> 绑定自己的域名</li></ul><h2 id="四、接下来">四、接下来</h2><p>先把内容写起来。主题、配色、插件这些，等写满 20 篇再说 —— 那些是最容易把时间吸走、又最没产出的东西。</p><hr><p>写下去，比写得好重要。</p>]]>
    </content>
    <id>https://rin3water.pages.dev/2026/09/25/hello-world/</id>
    <link href="https://rin3water.pages.dev/2026/09/25/hello-world/"/>
    <published>2026-09-25T08:30:00.000Z</published>
    <summary>博客上线了。这篇先讲清楚三件事：写什么、怎么发下一篇、常用语法速查。</summary>
    <title>开博第一篇：这个博客写什么，怎么写</title>
    <updated>2026-09-25T10:37:50.946Z</updated>
  </entry>
</feed>
