Next, further research about HCI layer of Bluetooth, achieve the connection between HCI layer and bluetooth audio transmission module.

在此基础上进一步对蓝牙HCI层进行了研究，并且实现了HCI层与语音传输模块的连接。

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API support for Bluetooth A2DP and HSP profiles lets applications query Bluetooth profiles for connected devices, audio state, and more, then notify the user.

API对蓝牙A2DP和HSP配置的支持使得应用可以查询连接的蓝牙设备所提供的蓝牙协定、音频栈等，并通知用户。

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You might then have to configure the Bluetooth chipset on the Linux device to receive and send SCO audio packets over the HCI transport interface rather than the PCM interface.

然后，您可能不得不在Linux设备上配置Bluetooth芯片组，以通过HCI传输接口而不是P CM接口收发sco音频数据分组。

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In fact, on the iPhone, it imitates a Bluetooth audio device, even though it doesn't do audio.

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Then, it took another eternity for the system to recognize my iPhone 4S to connect my Bluetooth Audio stream.

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The Bluetooth audio input allows you to play music from Bluetooth devices while the auxiliary input provides even more connectivity.

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