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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， ， < / 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
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， ， < / 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（ ） < / 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（ ） < / 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" >
< div class = "- topic/div div" >
< 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（ ） ， < / div >
< div class = "- topic/div div" > 增、减两个过程合起来算一个周期< / div >
< / div >
< / 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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< strong class = "+ topic/ph hi-d/b ph b" > PWM 信号< / strong >
< p class = "- topic/p p" data-ofbid = "d302585e107__20250121171808" > 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
占空比， ， ， < 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
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 = "d302585e118__20250121171808" > 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 = "d302585e122__20250121171808" > 结合上图，我们可以说：
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 = "d302585e124__20250121171808" > 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
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 >
< / li > < li class = "- topic/li li" data-ofbid = "d302585e127__20250121171808" >
< div class = "- topic/div div section" id = "id__id4" >
< strong class = "+ topic/ph hi-d/b ph b" > 增模式< / strong >
< p class = "- topic/p p" data-ofbid = "d302585e134__20250121171808" > 为了灵活调节 PWM
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 = "d302585e136__20250121171808" > 下图是由一个
< 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 >
< p class = "- topic/p p" data-ofbid = "d302585e148__20250121171808" > 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 >
（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 = "d302585e154__20250121171808" >
< 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 = "d302585e158__20250121171808" > ZRO< / dt > < dd class = "- topic/dd dd" >
< p class = "- topic/p p" data-ofbid = "d302585e162__20250121171808" > Zero Point 的缩写，锯齿波的起始点< / p >
< / dd > < / dl >
< / li > < li class = "- topic/li li" data-ofbid = "d302585e166__20250121171808" >
< 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 = "d302585e170__20250121171808" > PRD< / dt > < dd class = "- topic/dd dd" >
< p class = "- topic/p p" data-ofbid = "d302585e174__20250121171808" > Preiod Point 的缩写，锯齿波到达一个满周期的时间点< / p >
< / dd > < / dl >
< / li > < li class = "- topic/li li" data-ofbid = "d302585e178__20250121171808" >
< 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 = "d302585e182__20250121171808" > CMP< / dt > < dd class = "- topic/dd dd" >
< p class = "- topic/p p" data-ofbid = "d302585e186__20250121171808" > 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 >
< / dd > < / dl >
< / 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 >
< p class = "- topic/p p" data-ofbid = "d302585e192__20250121171808" > 实际上， ：
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 >
< / div > < p class = "- topic/p p" data-ofbid = "d302585e198__20250121171808" > 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 >
< / li > < li class = "- topic/li li" data-ofbid = "d302585e204__20250121171808" >
< div class = "- topic/div div section" id = "id__id5" >
< strong class = "+ topic/ph hi-d/b ph b" > 减模式< / strong >
< p class = "- topic/p p" data-ofbid = "d302585e211__20250121171808" > 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 >
< / div >
< / li > < li class = "- topic/li li" data-ofbid = "d302585e224__20250121171808" >
< div class = "- topic/div div section" id = "id__id6" >
< strong class = "+ topic/ph hi-d/b ph b" > 增减模式< / strong >
< p class = "- topic/p p" data-ofbid = "d302585e231__20250121171808" > 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 = "d302585e242__20250121171808" > 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 = "d302585e245__20250121171808" >
< p class = "- topic/p p" data-ofbid = "d302585e247__20250121171808" > 三种模式可以产生同样效果的 PWM 信号< / p >
< / li > < li class = "- topic/li li" data-ofbid = "d302585e250__20250121171808" >
< p class = "- topic/p p" data-ofbid = "d302585e252__20250121171808" > 配置 ZRO、CMP（ ） （ ） ， < / p >
< / li > < li class = "- topic/li li" data-ofbid = "d302585e255__20250121171808" >
< p class = "- topic/p p" data-ofbid = "d302585e257__20250121171808" > 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 = "d302585e262__20250121171808" >
< p class = "- topic/p p" data-ofbid = "d302585e264__20250121171808" > 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 = "d302585e270__20250121171808" >
< p class = "- topic/p p" data-ofbid = "d302585e272__20250121171808" > 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 = "d302585e278__20250121171808" >
< p class = "- topic/p p" data-ofbid = "d302585e280__20250121171808" > 为了简化使用， < 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 = "d302585e296__20250121171808" > 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 = "d302585e306__20250121171808" > 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 = "d302585e312__20250121171808" > 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 = "d302585e316__20250121171808" > 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 = "d302585e320__20250121171808" > 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 = "d302585e324__20250121171808" >
< p class = "- topic/p p" data-ofbid = "d302585e326__20250121171808" > 两个独立的单边输出< / p >
< / li > < li class = "- topic/li li" data-ofbid = "d302585e329__20250121171808" >
< p class = "- topic/p p" data-ofbid = "d302585e331__20250121171808" > 两个独立的双边对称输出< / p >
< / li > < li class = "- topic/li li" data-ofbid = "d302585e334__20250121171808" >
< p class = "- topic/p p" data-ofbid = "d302585e336__20250121171808" > 一个独立的双边非对称输出< / p >
< / li > < / ul > < / li > < li class = "- topic/li li" data-ofbid = "d302585e339__20250121171808" >
< p class = "- topic/p p" data-ofbid = "d302585e341__20250121171808" > 专用的 16 位可配置周期和频率的时基计数器（ ） < / p >
< / li > < li class = "- topic/li li" data-ofbid = "d302585e344__20250121171808" >
< p class = "- topic/p p" data-ofbid = "d302585e346__20250121171808" > 系统时钟 100 MHz< / p >
< / li > < li class = "- topic/li li" data-ofbid = "d302585e349__20250121171808" >
< p class = "- topic/p p" data-ofbid = "d302585e351__20250121171808" > 多种事件可配置产生对应的中断< / p >
< / li > < / ul >
< div class = "- topic/p p" data-ofbid = "d302585e356__20250121171808" > 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 = "d302585e387__20250121171808" > 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 = "d302585e441__20250121171808" > 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 >
< / div >
< / section > < / div > < / article > < / main > < / div >
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