> For the complete documentation index, see [llms.txt](https://book.bsdcn.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://book.bsdcn.org/bios/boot-qi-dong/usb-support.md).

# USB Support（USB 支持）

本选项用于配置 USB 设备在启动过程中的初始化程度。用户可以根据实际使用需求，选择 USB 设备的初始化级别，以平衡启动速度和设备可用性。

可用选项如下：

Disabled（禁用）

Full Initial（完全初始化）

Partial Initial（部分初始化）

具体说明：

如果禁用，所有 USB 设备（包括键盘、鼠标等）在操作系统启动前均不可用。

> **警告**
>
> 在部分机器上，该选项一旦关闭可能无法再次启用，具体请参考 BIOS 右上角的提示信息。由于现代设备通常不再提供 PS/2 接口，可能会导致系统无法正常操作。

如果选择部分初始化，则 USB 大容量存储设备（如 U 盘）以及部分 USB 端口或设备在操作系统启动前不可用。

如果选择完全初始化，所有 USB 设备在操作系统和启动自检（POST）过程中均可用。


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://book.bsdcn.org/bios/boot-qi-dong/usb-support.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.