This layer is literally the interface between the host (your computer) and the controller (the Bluetooth device).

这一层顾名思义就是主机(计算机)和控制器(蓝牙设备)之间的接口。

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The mobile device can interface directly with an output device using a wired or wireless connection, and can selectively operate as a host or client.

所述移动装置可使用有线或无线连接直接与输出装置介接，且可选择性地作为主机或客户端而操作。

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The new 12 Gbps specification will eventually allow the host system to decide how much power a storage device with the interface should use, allowing up 25 W. It will also allow atomic writes, which will improve system performance as well as providing more resilient system designs.

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