下面是从USB 2.0的标准文本上摘下来的一段:<br /><br /><H3>9.4 Standard Device Requests</H3>This section describes the standard device requests defined for all USB devices. Table 9-3 outlines the standard device requests, while Table 9-4 and Table 9-5 give the standard request codes and descriptor types, respectively.<br /><br />USB devices must respond to standard device requests, even if the device has not yet been assigned an address or has not been configured.<br /><br /><hr>这里说的非常清楚,“USB设备必须响应标准的设备请求,即使设备还未被分配地址或被配置”
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