cherry-embedded
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CherryUSB
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<li class="toctree-l1"><a class="reference internal" href="../usbip/chipidea.html">CHIPIDEA</a></li>
<li class="toctree-l1"><a class="reference internal" href="../usbip/dwc2.html">DWC2</a></li>
<li class="toctree-l1"><a class="reference internal" href="../usbip/musb.html">MUSB</a></li>
<li class="toctree-l1"><a class="reference internal" href="../usbip/fotg210.html">FOTG210</a></li>
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<li class="toctree-l1"><a class="reference internal" href="../usbip/dwc3.html">DWC3</a></li>
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<li class="toctree-l1"><a class="reference internal" href="../tools/index.html">chryusb_configurator</a></li>
<li class="toctree-l1"><a class="reference internal" href="../tools/index.html#usb-protocol-suite">力科 USB Protocol Suite</a></li>
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  <section id="q-a">
<h1>Q &amp; A<a class="headerlink" href="#q-a" title="Link to this heading"></a></h1>
<section id="id1">
<h2>移植提问模板<a class="headerlink" href="#id1" title="Link to this heading"></a></h2>
<p>请在下列途径提交问题：
- RT-Thread 官方论坛: <a class="reference external" href="https://club.rt-thread.org/ask/tag/5f5f851966917b14.html">https://club.rt-thread.org/ask/tag/5f5f851966917b14.html</a>
- Github issue: <a class="reference external" href="https://github.com/cherry-embedded/CherryUSB/issues/new/choose">https://github.com/cherry-embedded/CherryUSB/issues/new/choose</a></p>
<p>提问中请包含以下信息：</p>
<ul class="simple">
<li><p>使用的版本</p></li>
<li><p>使用的板子，引脚，USB IP</p></li>
<li><p>是否配置 USB 中断，USB 时钟，USB 引脚，USB phy 配置，以及 USB 寄存器地址是否正确，截图</p></li>
<li><p>是否能进 USB 中断</p></li>
<li><p>芯片是否带有 cache功能，是否做了 no cache 处理，截图</p></li>
<li><p>USB 电路是否画正确，是否使用杜邦线连接，是否直连，如果正常，请说明正常原因</p></li>
<li><p>如果能进中断，配置 <strong>#define CONFIG_USB_DBG_LEVEL USB_DBG_LOG</strong> 并提供 log，仅限商业 IP, 其余 IP 禁止开启 log，否则无法枚举</p></li>
<li><p>是否流片并销售</p></li>
</ul>
</section>
<section id="id2">
<h2>其余问题提问模板<a class="headerlink" href="#id2" title="Link to this heading"></a></h2>
<p>具体说明现象，复现方式，使用我提供的 demo 再测试，以及提供完整 log</p>
</section>
<section id="cherryusb">
<h2>CherryUSB 性能能到多少<a class="headerlink" href="#cherryusb" title="Link to this heading"></a></h2>
<p>参考 <a class="reference internal" href="../show/index.html#performace-show"><span class="std std-ref">性能展示</span></a></p>
</section>
<section id="st-ip">
<h2>ST IP 命名问题<a class="headerlink" href="#st-ip" title="Link to this heading"></a></h2>
<p>ST 命名为 USB_OTG_FS, USB_OTG_HS，并不是说明本身是高速或者全速，只是代表可以支持到高速，但是本身都是全速，需要外挂高速phy。因此，提问禁止说这两个词，请使用 USB0(PA11/PA12),USB1(PB14/PB15) 代替。其余国产厂家同理。</p>
</section>
<section id="gd-ip">
<h2>GD IP 问题<a class="headerlink" href="#gd-ip" title="Link to this heading"></a></h2>
<p>GD IP 采用 DWC2，但是读取的硬件参数都是 0（我也不懂为什么不给人知道），因此需要用户自行知道硬件信息，从 1.5.0 开始由于需要读取硬件信息，因此无法直接使用。</p>
<p>其次 GD 复位以后无法使用 EPDIS 功能关闭端点，需要用户删除 reset 中断中的以下代码：</p>
<div class="highlight-C notranslate"><div class="highlight"><pre><span></span><span class="n">USB_OTG_INEP</span><span class="p">(</span><span class="n">i</span><span class="p">)</span><span class="o">-&gt;</span><span class="n">DIEPCTL</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">(</span><span class="n">USB_OTG_DIEPCTL_EPDIS</span><span class="w"> </span><span class="o">|</span><span class="w"> </span><span class="n">USB_OTG_DIEPCTL_SNAK</span><span class="p">);</span>
<span class="n">USB_OTG_OUTEP</span><span class="p">(</span><span class="n">i</span><span class="p">)</span><span class="o">-&gt;</span><span class="n">DOEPCTL</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">(</span><span class="n">USB_OTG_DOEPCTL_EPDIS</span><span class="w"> </span><span class="o">|</span><span class="w"> </span><span class="n">USB_OTG_DOEPCTL_SNAK</span><span class="p">);</span>
</pre></div>
</div>
<p>除此之外可能存在其他未知 BUG，请自行测试。</p>
</section>
<section id="usb-log-dbg">
<h2>开启 USB_LOG_DBG 后无法枚举<a class="headerlink" href="#usb-log-dbg" title="Link to this heading"></a></h2>
<p>有且仅有商业性 IP 开启后可以枚举，其余 IP 禁止开启，否则无法枚举。懂得都懂。</p>
</section>
<section id="usb3-cv">
<h2>USB3 CV测试用哪个版本<a class="headerlink" href="#usb3-cv" title="Link to this heading"></a></h2>
<p>1.4.3 版本及以上</p>
</section>
<section id="ep-addr-xxx-fifo-overflow">
<h2>Ep addr XXX fifo overflow<a class="headerlink" href="#ep-addr-xxx-fifo-overflow" title="Link to this heading"></a></h2>
<figure class="align-default">
<img alt="../_images/question1.png" src="../_images/question1.png" />
</figure>
<p>该错误表示该端点默认设置的 fifo 空间不够用，需要增大 fifo 空间，通常见于 DWC2/MUSB IP。FIFO 设置参考相关的 glue 文件。</p>
</section>
<section id="ep-addr-xxx-overflow">
<h2>Ep addr XXX overflow<a class="headerlink" href="#ep-addr-xxx-overflow" title="Link to this heading"></a></h2>
<figure class="align-default">
<img alt="../_images/question2.png" src="../_images/question2.png" />
</figure>
<p>该错误表示该 IP 硬件上没有这么多端点, 请更换 IP or 减少端点使用。
当然也可以修改为双向端点，考虑到不是所有的 IP 都支持双向端点，因此默认 demo 不做双向功能，举例默认是 81 02 这样的而不是 81 01，如果支持，自行修改。某些 IP 双向端点可能会占用相同的硬件信息，不一定能同时使用，自行检查。</p>
</section>
<section id="this-dwc2-version-does-not-support-dma-mode-so-stop-working">
<h2>This dwc2 version does not support dma mode, so stop working<a class="headerlink" href="#this-dwc2-version-does-not-support-dma-mode-so-stop-working" title="Link to this heading"></a></h2>
<p>该 DWC2 版本不支持 dma 模式，禁止使用。不使用 DMA 模式会频繁触发 NAK 中断（大概几十us一次），CPU 占用率过高。</p>
</section>
<section id="otg">
<h2>OTG 有哪些芯片支持<a class="headerlink" href="#otg" title="Link to this heading"></a></h2>
<p>当前主线仅 HPM 芯片支持 OTG 功能，通过 ID 引脚自动切换主从模式，其他芯片请使用手动切换模式 OR 自行实现添加 ID 识别的驱动。</p>
</section>
<section id="pc-com">
<h2>PC 识别的 COM 口如何更改名称<a class="headerlink" href="#pc-com" title="Link to this heading"></a></h2>
<p>这是微软对 CDC ACM 的驱动问题，无法修改，如需修改，请联系微软并缴纳费用+编写驱动后即可更改。</p>
</section>
<section id="connect-disconnect-event">
<h2>connect 和 disconnect event 不触发<a class="headerlink" href="#connect-disconnect-event" title="Link to this heading"></a></h2>
<p>当前仅 hpm 芯片支持 connect 和 disconnect 事件，其他芯片请使用 USB 检测 vbus 电路。DWC2 IP 支持，但是由于需要占用引脚，并且大多是log 口，然后不同使能的配置也不一样，因此不做支持。</p>
</section>
<section id="has-include">
<h2>__has_include 报错<a class="headerlink" href="#has-include" title="Link to this heading"></a></h2>
<p>如果报错，需要编译器支持 c99 语法，如果是 keil，请用 ac6 编译器</p>
</section>
<section id="config-usb-hs">
<h2>CONFIG_USB_HS 何时使用<a class="headerlink" href="#config-usb-hs" title="Link to this heading"></a></h2>
<p>当你的芯片硬件支持高速，并想初始化成高速模式时开启，相关 IP 会根据该宏配置内部或者外部 高速 PHY。</p>
</section>
<section id="failed-to-enable-port">
<h2>Failed to enable port<a class="headerlink" href="#failed-to-enable-port" title="Link to this heading"></a></h2>
<p>供电不足或者硬件 USB 电路问题</p>
</section>
<section id="usb-host-urb-12-14">
<h2>移植 usb host 出现 urb  返回 -12/-14<a class="headerlink" href="#usb-host-urb-12-14" title="Link to this heading"></a></h2>
<p>检查 phy 配置，cache 配置（如果有），电源供电（建议自供电）</p>
</section>
<section id="usb-err-nak">
<h2>USB_ERR_NAK 说明<a class="headerlink" href="#usb-err-nak" title="Link to this heading"></a></h2>
<p>USB_ERR_NAK 只存在于 DWC2 buffer dma/slave 模式(我们不使用 slave 模式)，DWC2 在 buffer dma模式下对于中断传输不支持硬件处理 NAK 中断，因此需要软件处理，导致 NAK 中断非常多，建议搭配定时器使用。
DWC2 scatter/gather dma 模式下全部由硬件处理，但是不支持 split 传输。总结， <strong>食之无味，弃之可惜</strong>。</p>
</section>
<section id="usb-host-usb">
<h2>USB host 连接 USB 网卡问题<a class="headerlink" href="#usb-host-usb" title="Link to this heading"></a></h2>
<p>表现为能识别网卡并且分配到 IP 地址，但是无法 ping 通，这是因为网卡自身需要开启自动拨号，通常需要使用 AT 口设置。具体为 EC20/ML307 等模块。</p>
</section>
<section id="config-usb-dcache-enable">
<h2>什么时候需要开启 CONFIG_USB_DCACHE_ENABLE<a class="headerlink" href="#config-usb-dcache-enable" title="Link to this heading"></a></h2>
<p>当芯片带有 cache 功能，并且没有使用 no cache ram 时需要开启此宏以保证数据一致性。 <strong>使用 EHCI 时，内部依旧需要使用 nocache ram</strong>。通常，对于第三方平台或者组件，没有使用 no cache ram 宏修饰，都是使用全局变量或者 malloc 等
操作，这部分 RAM 通常是走 cache 的，因此需要开启此宏。建议第三方平台使用时，必须开启。</p>
</section>
<section id="ip">
<h2>哪些 IP 对数据有对齐要求<a class="headerlink" href="#ip" title="Link to this heading"></a></h2>
<ul class="simple">
<li><p>在未开启 CONFIG_USB_DCACHE_ENABLE 时，仅 DWC2/WCH/AIC IP 需要 4字节对齐，其余 1字节对齐即可。</p></li>
<li><p>在开启 CONFIG_USB_DCACHE_ENABLE 时，所有 IP 都需要对齐到 CONFIG_USB_ALIGN_SIZE 字节</p></li>
</ul>
</section>
</section>


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