说明：  《蓝牙协议及其源代码分析》一书的详细PDF版本。内容涉及了对于蓝牙协议栈的详细剖析，并提供了大量源代码，是蓝牙初学者的帮手！
(Bluetooth protocol and its source code analysis, a detailed PDF version of the book. Covers a detailed analysis of the Bluetooth protocol stack, and provides a lot of source code, is the helper of the Bluetooth beginners!)