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<div class=" wh_topic_content body "><main role="main"><article class="- topic/topic topic" role="article" aria-labelledby="ariaid-title1"><span class="edit-link" style="font-size:12px; opacity:0.6; text-align:right; vertical-align:middle"><a target="_blank" href="http://172.16.35.88/tasks/jdssno1uvvbf2mltu9kb9v3if05d5gopuakboe8hlud18rma/edit/F:/aicdita/aicdita-cn/topics/sdk/pwm/pwm_user_guide.dita">Edit online</a></span><h1 class="- topic/title title topictitle1" id="ariaid-title1">PWM 使用指南</h1><div class="date inPage">2 Dec 2024</div><div style="color: gray;">
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Read time: 3 minute(s)
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</div><div class="- topic/body body"><div class="table-container"><table class="- topic/table table frame-all" id="id__table_aw1_yh3_fdc" data-ofbid="id__table_aw1_yh3_fdc" data-cols="2"><caption class="- topic/title title tablecap" data-caption-side="top" data-is-repeated="true"><span class="table--title-label">表<span class="table--title-label-number"> 1</span><span class="table--title-label-punctuation">. </span></span><span class="table--title">术语定义</span></caption><colgroup><col/><col/></colgroup><thead class="- topic/thead thead"><tr class="- topic/row"><th class="- topic/entry entry colsep-1 rowsep-1" id="id__table_aw1_yh3_fdc__entry__1">术语/缩略语</th><th class="- topic/entry entry colsep-0 rowsep-1" id="id__table_aw1_yh3_fdc__entry__2">定义及说明</th></tr></thead><tbody class="- topic/tbody tbody"><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__1">PWM</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__2">Pulse-Width Modulation，脉冲宽度控制，简称脉宽调制</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__1">EPWM</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__2">Enhanced Pulse-Width Modulation, 增强型脉冲宽度控制（<span class="- topic/ph ph">Luban-Lite</span> 中
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EPWM 功能与 PWM 相同，如无特殊说明，两者通用）</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__1">TBC</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__2">Time Base Counter，时基计数器，用于产生锯齿波</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__1">占空比</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__2">PWM 信号中，高电平保持的时间 与 该 PWM 时钟周期的时间之比</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__1">分辨率</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__2">占空比最小能达到多少，如 8 位的 PWM 理论分辨率是 1:255</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__1">Up Count</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__2">增模式, 计数方式是递增计数，如从 0 计数到 80、之后又从 0 到 80（波形是锯齿波）</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__1">Down Count</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__2">减模式, 计数方式是递减计数，如从 80 计数到 0、之后又从 80 到 0（波形是锯齿波）</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__1">单斜率</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__2">单个方向的计数，增模式、减模式都属于单斜率</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__1">Up&Down Count</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_aw1_yh3_fdc__entry__2">
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<div class="- topic/div div">
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<div class="- topic/div div"> 增减模式，计数方向有两个，如从 0 计数到 80、然后从 80 到 0（波形是三角波），</div>
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<div class="- topic/div div"> 增、减两个过程合起来算一个周期</div>
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</div>
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</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-0" headers="id__table_aw1_yh3_fdc__entry__1">双斜率</td><td class="- topic/entry entry colsep-0 rowsep-0" headers="id__table_aw1_yh3_fdc__entry__2">两个方向的计数，增减模式属于双斜率</td></tr></tbody></table></div><section class="- topic/section section" id="id__section_w5l_rwn_4dc" data-ofbid="id__section_w5l_rwn_4dc"><h2 class="- topic/title title sectiontitle">PWM 工作原理</h2>
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<ul class="- topic/ul ul" id="id__ul_kdh_twn_4dc" data-ofbid="id__ul_kdh_twn_4dc"><li class="- topic/li li" data-ofbid="d252320e99__20250121171704">
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<div class="- topic/div div section" id="id__id3">
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<strong class="+ topic/ph hi-d/b ph b">PWM 信号</strong>
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<p class="- topic/p p" data-ofbid="d252320e106__20250121171704"> PWM 信号通常由一列占空比不同的矩形脉冲构成，其占空比可以调节。用数字输出来控制 PWM
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占空比，占空比提高意味着高电平脉宽增大，输出的能量就会增加，PWM 就相当于一个 <strong class="+ topic/ph hi-d/b ph b">功率版的 DA 转换模块</strong>。下图是一个典型的
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PWM 信号波形：</p><figure class="- topic/fig fig fignone" id="id__id8" data-ofbid="id__id8"><br/><div class="imagecenter"><img class="- topic/image image imagecenter" id="id__image_vwl_rwn_4dc" src="../../../images/pwm/pwm_wave.png" width="384" alt="pwm_wave1"/></div><br/><figcaption data-caption-side="bottom" class="- topic/title title figcapcenter"><span class="figtitleprefix fig--title-label">图<span class="fig--title-label-number"> 1</span><span class="fig--title-label-punctuation">. </span></span><span class="fig--title">典型的 PWM 信号波形</span></figcaption></figure><p class="- topic/p p" data-ofbid="d252320e117__20250121171704">占空比的计算方法： <code class="+ topic/ph pr-d/codeph ph codeph">占空比=(脉宽时间/周期)*100%</code></p><p class="- topic/p p" data-ofbid="d252320e121__20250121171704">结合上图，我们可以说：
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脉宽时间 1 相比 脉宽时间 2 提供较小的占空比。</p><p class="- topic/p p" data-ofbid="d252320e123__20250121171704"> PWM 通常用于背光亮度调节、电机控制、舵机控制等。本文仅限于 PWM
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调节背光的功能，通过调节 PWM 中的占空比，达到控制 LED 背光电流的通和断，进而可调整背光亮度。</p></div>
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</li><li class="- topic/li li" data-ofbid="d252320e126__20250121171704">
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<div class="- topic/div div section" id="id__id4">
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<strong class="+ topic/ph hi-d/b ph b">增模式</strong>
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<p class="- topic/p p" data-ofbid="d252320e133__20250121171704"> 为了灵活调节 PWM
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信号的占空比，要先想办法产生一个递增、或者递减的锯齿波信号，另外再结合一个比较器来跟一个阈值进行比较，当满足条件时进行电平反转，这样达到的效果就是通过调节“阈值”来调节了占空比。</p><p class="- topic/p p" data-ofbid="d252320e135__20250121171704">下图是由一个
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<strong class="+ topic/ph hi-d/b ph b">递增变化</strong> 的锯齿波产生 PWM 信号的过程：</p><figure class="- topic/fig fig fignone" id="id__id9" data-ofbid="id__id9"><br/><div class="imagecenter"><img class="- topic/image image imagecenter" id="id__image_wwl_rwn_4dc" src="../../../images/pwm/generate_pwm_up.png" alt="generate_pwm_up"/></div><br/><figcaption data-caption-side="bottom" class="- topic/title title figcapcenter"><span class="figtitleprefix fig--title-label">图<span class="fig--title-label-number"> 2</span><span class="fig--title-label-punctuation">. </span></span><span class="fig--title">由增模式锯齿波产生 PWM 信号的过程示意图</span></figcaption></figure>
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<p class="- topic/p p" data-ofbid="d252320e147__20250121171704">图中 Tpwm 表示 PWM 信号的周期值，另外有 <strong class="+ topic/ph hi-d/b ph b">三个关键的时间点（下文简称关键时点）</strong>
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（标注橙色圆圈，为了简洁只标注了最后一个周期）在下文中会频繁使用：</p><ul class="- topic/ul ul simple" id="id__ul_xwl_rwn_4dc" data-ofbid="id__ul_xwl_rwn_4dc"><li class="- topic/li li" data-ofbid="d252320e153__20250121171704">
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<dl class="- topic/dl dl simple" id="id__dl_ywl_rwn_4dc" data-ofbid="id__dl_ywl_rwn_4dc"><dt class="- topic/dt dt dlterm" data-ofbid="d252320e157__20250121171704">ZRO</dt><dd class="- topic/dd dd">
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<p class="- topic/p p" data-ofbid="d252320e161__20250121171704">Zero Point 的缩写，锯齿波的起始点</p>
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</dd></dl>
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</li><li class="- topic/li li" data-ofbid="d252320e165__20250121171704">
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<dl class="- topic/dl dl simple" id="id__dl_zwl_rwn_4dc" data-ofbid="id__dl_zwl_rwn_4dc"><dt class="- topic/dt dt dlterm" data-ofbid="d252320e169__20250121171704">PRD</dt><dd class="- topic/dd dd">
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<p class="- topic/p p" data-ofbid="d252320e173__20250121171704">Preiod Point 的缩写，锯齿波到达一个满周期的时间点</p>
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</dd></dl>
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</li><li class="- topic/li li" data-ofbid="d252320e177__20250121171704">
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<dl class="- topic/dl dl simple" id="id__dl_axl_rwn_4dc" data-ofbid="id__dl_axl_rwn_4dc"><dt class="- topic/dt dt dlterm" data-ofbid="d252320e181__20250121171704">CMP</dt><dd class="- topic/dd dd">
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<p class="- topic/p p" data-ofbid="d252320e185__20250121171704">Compare Point 的缩写，锯齿波到达了阈值的时间点，如上图中的 CMP 值为 7。</p>
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</dd></dl>
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</li></ul><div class="- topic/note note tip note_tip" id="id__note_kyl_qn3_ddc" data-ofbid="id__note_kyl_qn3_ddc"><span class="note__title">提示：</span>
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<p class="- topic/p p" data-ofbid="d252320e191__20250121171704"> 实际上，PWM 模块支持设置两个 CMP 值：CMPA 和 CMPB。受限于 OS 中 PWM 子系统架构的接口设计，根据 duty
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参数计算只能得到一个 CMP 值，所以 <strong class="+ topic/ph hi-d/b ph b">CMPB 和 CMPA 实际上数值保持一致</strong>。</p>
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</div><p class="- topic/p p" data-ofbid="d252320e197__20250121171704">这些关键时点的触发行为 Action 有四种类型，详见 <a xml:lang="zh-CN" lang="zh-CN" class="- topic/xref xref" href="pwm_config.html">PWM 配置</a></p></div>
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</li><li class="- topic/li li" data-ofbid="d252320e203__20250121171704">
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||
<div class="- topic/div div section" id="id__id5">
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<strong class="+ topic/ph hi-d/b ph b">减模式</strong>
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<p class="- topic/p p" data-ofbid="d252320e210__20250121171704">下图是由一个 <strong class="+ topic/ph hi-d/b ph b">递减变化</strong> 的锯齿波产生 PWM 信号的过程： </p><figure class="- topic/fig fig fignone" id="id__id10" data-ofbid="id__id10"><br/><div class="imagecenter"><img class="- topic/image image imagecenter" id="id__image_bxl_rwn_4dc" src="../../../images/pwm/generate_pwm_down.png" alt="generate_pwm_down"/></div><br/><figcaption data-caption-side="bottom" class="- topic/title title figcapcenter"><span class="figtitleprefix fig--title-label">图<span class="fig--title-label-number"> 3</span><span class="fig--title-label-punctuation">. </span></span><span class="fig--title">由减模式锯齿波产生 PWM 信号的过程示意图</span></figcaption></figure>
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</div>
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||
</li><li class="- topic/li li" data-ofbid="d252320e223__20250121171704">
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<div class="- topic/div div section" id="id__id6">
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<strong class="+ topic/ph hi-d/b ph b">增减模式</strong>
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<p class="- topic/p p" data-ofbid="d252320e230__20250121171704">下图是由一个 <strong class="+ topic/ph hi-d/b ph b">同时有递减、递减变化</strong> 的锯齿波产生 PWM 信号的过程：</p><figure class="- topic/fig fig fignone" id="id__id11" data-ofbid="id__id11"><br/><div class="imagecenter"><img class="- topic/image image imagecenter" id="id__image_cxl_rwn_4dc" src="../../../images/pwm/generate_pwm_up_down.png" alt="generate_pwm_updown.png"/></div><br/><figcaption data-caption-side="bottom" class="- topic/title title figcapcenter"><span class="figtitleprefix fig--title-label">图<span class="fig--title-label-number"> 4</span><span class="fig--title-label-punctuation">. </span></span><span class="fig--title">由增减模式锯齿波产生 PWM 信号的过程示意图</span></figcaption></figure><p class="- topic/p p" data-ofbid="d252320e241__20250121171704">比较以上三种模式的 PWM 产生过程，可以看到：</p><ul class="- topic/ul ul simple" id="id__ul_dxl_rwn_4dc" data-ofbid="id__ul_dxl_rwn_4dc"><li class="- topic/li li" data-ofbid="d252320e244__20250121171704">
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<p class="- topic/p p" data-ofbid="d252320e246__20250121171704">三种模式可以产生同样效果的 PWM 信号</p>
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</li><li class="- topic/li li" data-ofbid="d252320e249__20250121171704">
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||
<p class="- topic/p p" data-ofbid="d252320e251__20250121171704">配置 ZRO、CMP（增减模式中有两处 CMP）、PRD 的触发行为（Action），可产生不同的 PWM 信号</p>
|
||
</li><li class="- topic/li li" data-ofbid="d252320e254__20250121171704">
|
||
<p class="- topic/p p" data-ofbid="d252320e256__20250121171704">CMP 的取值，直接决定了占空比，所以用户看到的 <strong class="+ topic/ph hi-d/b ph b">调节占空比就是通过调节 CMP 值来实现</strong></p>
|
||
</li><li class="- topic/li li" data-ofbid="d252320e261__20250121171704">
|
||
<p class="- topic/p p" data-ofbid="d252320e263__20250121171704">PRD 的值，决定了 PWM 信号的周期值 Tpwm</p>
|
||
</li></ul><div class="- topic/note note tip note_tip" id="id__note_lyl_qn3_ddc" data-ofbid="id__note_lyl_qn3_ddc"><span class="note__title">提示：</span>
|
||
<ol class="- topic/ol ol arabic simple" id="id__ol_exl_rwn_4dc" data-ofbid="id__ol_exl_rwn_4dc"><li class="- topic/li li" data-ofbid="d252320e269__20250121171704">
|
||
<p class="- topic/p p" data-ofbid="d252320e271__20250121171704">具体选择哪一种模式，要依据用户场景的需求特点，建议按 <strong class="+ topic/ph hi-d/b ph b">从简原则：首选相对简单的单斜率模式</strong>。</p>
|
||
</li><li class="- topic/li li" data-ofbid="d252320e277__20250121171704">
|
||
<p class="- topic/p p" data-ofbid="d252320e279__20250121171704">为了简化使用，RTOS 中默认只使用 <strong class="+ topic/ph hi-d/b ph b">增模式</strong>。</p>
|
||
</li></ol>
|
||
</div></div>
|
||
</li></ul>
|
||
</section><section class="- topic/section section" id="id__section_rvr_rwn_4dc" data-ofbid="id__section_rvr_rwn_4dc"><h2 class="- topic/title title sectiontitle">PWM 功能简介</h2>
|
||
|
||
<div class="- topic/div div section" id="id__id7">
|
||
<p class="- topic/p p" data-ofbid="d252320e295__20250121171704">PWM 的硬件设计，使用时基计数器产生上述的锯齿波信号，使用一个比较器可同时产生两路 PWM 信号。 PWM 模块的硬件原理图可简化如下：</p>
|
||
<figure class="- topic/fig fig fignone" id="id__id12" data-ofbid="id__id12"><br/><div class="imagecenter"><img class="- topic/image image imagecenter" id="id__image_hwr_rwn_4dc" src="../../../images/pwm/pwm_hw_system.png" width="480" alt="pwm_hw_system"/></div><br/><figcaption data-caption-side="bottom" class="- topic/title title figcapcenter"><span class="figtitleprefix fig--title-label">图<span class="fig--title-label-number"> 5</span><span class="fig--title-label-punctuation">. </span></span><span class="fig--title">简化的 PWM 硬件框图</span></figcaption></figure>
|
||
<p class="- topic/p p" data-ofbid="d252320e305__20250121171704">PWM 模块共支持 4 个 PWM 通道，上图只画出了其中一个 PWM 通道，每个通道有 PWMx0 和 PWMx1 两个输出信号，对应 DTS 参数中的
|
||
action0 和 action1 配置。 <a xml:lang="zh-CN" lang="zh-CN" class="- topic/xref xref" href="pwm_config.html">PWM 配置</a></p>
|
||
<p class="- topic/p p" data-ofbid="d252320e311__20250121171704">PWM 模块支持的功能特性有：</p>
|
||
<ul class="- topic/ul ul simple" id="id__ul_iwr_rwn_4dc" data-ofbid="id__ul_iwr_rwn_4dc"><li class="- topic/li li" data-ofbid="d252320e315__20250121171704">每个 PWM 通道可以产生 PWMx0 和 PWMx1 输出信号，配置规则如下：<div class="- topic/note note note note_note" id="id__note_myl_qn3_ddc" data-ofbid="id__note_myl_qn3_ddc"><span class="note__title">注：</span>
|
||
<p class="- topic/p p" data-ofbid="d252320e319__20250121171704">在用户手册 > 接口 > PWM 模块中，上述两个 PWM 输出信号被称作 PWMxA 和 PWMxB。为了避免和阈值 CMPA 和
|
||
CMPB 混淆，软件设计中将两个输出信号称作 PWMx0 和 PWMx1。</p>
|
||
</div><ul class="- topic/ul ul" id="id__ul_kwr_rwn_4dc" data-ofbid="id__ul_kwr_rwn_4dc"><li class="- topic/li li" data-ofbid="d252320e323__20250121171704">
|
||
<p class="- topic/p p" data-ofbid="d252320e325__20250121171704">两个独立的单边输出</p>
|
||
</li><li class="- topic/li li" data-ofbid="d252320e328__20250121171704">
|
||
<p class="- topic/p p" data-ofbid="d252320e330__20250121171704">两个独立的双边对称输出</p>
|
||
</li><li class="- topic/li li" data-ofbid="d252320e333__20250121171704">
|
||
<p class="- topic/p p" data-ofbid="d252320e335__20250121171704">一个独立的双边非对称输出</p>
|
||
</li></ul></li><li class="- topic/li li" data-ofbid="d252320e338__20250121171704">
|
||
<p class="- topic/p p" data-ofbid="d252320e340__20250121171704">专用的 16 位可配置周期和频率的时基计数器（Time Base Counter）</p>
|
||
</li><li class="- topic/li li" data-ofbid="d252320e343__20250121171704">
|
||
<p class="- topic/p p" data-ofbid="d252320e345__20250121171704">系统时钟 100 MHz</p>
|
||
</li><li class="- topic/li li" data-ofbid="d252320e348__20250121171704">
|
||
<p class="- topic/p p" data-ofbid="d252320e350__20250121171704">多种事件可配置产生对应的中断</p>
|
||
</li></ul>
|
||
<div class="- topic/p p" data-ofbid="d252320e355__20250121171704">在 CMPA 和 CMPB 同时使用的情况下，锯齿波就会有两次和阈值的比较，共产生 4 个关键时点：<div class="table-container"><table class="- topic/table table frame-all" id="id__table_lwr_rwn_4dc" data-ofbid="id__table_lwr_rwn_4dc" data-cols="3"><caption></caption><colgroup><col style="width:29.673590504451035%"/><col style="width:35.311572700296736%"/><col style="width:35.01483679525222%"/></colgroup><thead class="- topic/thead thead"><tr class="- topic/row"><th class="- topic/entry entry colsep-1 rowsep-1" id="id__table_lwr_rwn_4dc__entry__1">锯齿波信号波段</th><th class="- topic/entry entry colsep-1 rowsep-1" id="id__table_lwr_rwn_4dc__entry__2">CMPA</th><th class="- topic/entry entry colsep-0 rowsep-1" id="id__table_lwr_rwn_4dc__entry__3">CMPB</th></tr></thead><tbody class="- topic/tbody tbody"><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_lwr_rwn_4dc__entry__1">增斜率段</td><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_lwr_rwn_4dc__entry__2">CAU (Compare A Up)</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_lwr_rwn_4dc__entry__3">CBU (Compare B Up)</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-0" headers="id__table_lwr_rwn_4dc__entry__1">减斜率段</td><td class="- topic/entry entry colsep-1 rowsep-0" headers="id__table_lwr_rwn_4dc__entry__2">CAD (Compare A Down)</td><td class="- topic/entry entry colsep-0 rowsep-0" headers="id__table_lwr_rwn_4dc__entry__3">CBD (Compare B Down)</td></tr></tbody></table></div></div>
|
||
<p class="- topic/p p" data-ofbid="d252320e386__20250121171704">以增减模式的锯齿波为例，共 6 个关键时点：</p>
|
||
<figure class="- topic/fig fig fignone" id="id__id13" data-ofbid="id__id13"><br/><div class="imagecenter"><img class="- topic/image image imagecenter" id="id__image_mwr_rwn_4dc" src="../../../images/pwm/pwm_cmpa_cmpb.png" alt="cmpa_cmpb"/></div><br/><figcaption data-caption-side="bottom" class="- topic/title title figcapcenter"><span class="figtitleprefix fig--title-label">图<span class="fig--title-label-number"> 6</span><span class="fig--title-label-punctuation">. </span></span><span class="fig--title">增减模式的 6 个关键时点</span></figcaption></figure>
|
||
<div class="table-container"><table class="- topic/table table frame-all" id="id__table_nwr_rwn_4dc" data-ofbid="id__table_nwr_rwn_4dc" data-cols="2"><caption class="- topic/title title tablecap" data-caption-side="top" data-is-repeated="true"><span class="table--title-label">表<span class="table--title-label-number"> 2</span><span class="table--title-label-punctuation">. </span></span><span class="table--title">增减模式下关机时点的触发行为配置</span></caption><colgroup><col style="width:48.07692307692307%"/><col style="width:51.92307692307693%"/></colgroup><thead class="- topic/thead thead"><tr class="- topic/row"><th class="- topic/entry entry colsep-1 rowsep-1" id="id__table_nwr_rwn_4dc__entry__1">关键时点</th><th class="- topic/entry entry colsep-0 rowsep-1" id="id__table_nwr_rwn_4dc__entry__2">Action 类型</th></tr></thead><tbody class="- topic/tbody tbody"><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_nwr_rwn_4dc__entry__1">CBD</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_nwr_rwn_4dc__entry__2">none</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_nwr_rwn_4dc__entry__1">CBU</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_nwr_rwn_4dc__entry__2">none</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_nwr_rwn_4dc__entry__1">CAD</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_nwr_rwn_4dc__entry__2">high</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_nwr_rwn_4dc__entry__1">CAU</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_nwr_rwn_4dc__entry__2">none</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="id__table_nwr_rwn_4dc__entry__1">PRD</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="id__table_nwr_rwn_4dc__entry__2">low</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-0" headers="id__table_nwr_rwn_4dc__entry__1">ZRO</td><td class="- topic/entry entry colsep-0 rowsep-0" headers="id__table_nwr_rwn_4dc__entry__2">low</td></tr></tbody></table></div>
|
||
<p class="- topic/p p" data-ofbid="d252320e440__20250121171704">关于行为类型定义，见 <a xml:lang="zh-CN" lang="zh-CN" class="- topic/xref xref" href="pwm_config.html">PWM 配置</a>。</p>
|
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