一款很好的介绍蓝牙原理及应用的书籍，包括各种profile介绍，以及在实际应用的例子介绍。-A good introduction to the theory and applications of Bluetooth books, including profile descr iptions, and examples of practical application in the introduction.

nordic的蓝牙应用描述文档，有例子有说明，值得初学者好好学习。-nordic Bluetooth application descr iption document, there is an example of a note, it is worth a beginner to learn.