Design And Implementation Of Bluetooth Application Programming Interface In Linux

Recently with the growth of market demand for various bluetooth applications,bluetooth stack is also expanding it's function.The design of bluetooth application programming interface save development costs and shorten the development period of bluetooth products.This thesis come from Hitachi ‘projector.in order to support high-quality audio playback and wireless human interface devices input function,the projector use bluetooth technology.Since Hitachi is already has a mature bluetooth application which is base on TI's protocol stack API,and the projector uses imx6 application processor which dose not support TI protocol stack,in order not to reconstruct the original application,so it is necessary to custom Bluetooth API accroding to the Bluetooth hardware and application functional requirements.This thesis design a set of bluetooth API based on linux platform and common bluetooth stack.it is compatible with most bluetooth hardware devices that have been certified by SIG.Based on this bluetooth API,the application developers do not have to do extensive research on the Bluetooth protocol specific technology,to develop bluetooth applications in linux.This design solves issues that the bluetooth hardware devices which the projector need do not have suitable bluetooth API.The content of this thesis includes four aspects as follows:Firstly,base on the analysis of project functional requirements,this thesis chose appropriate protocol stack and analyze its architecture,then come up with the overall design framework for the bluetooth software.Secondly,design and implement the common functions of bluetooth.It allow linux host realize local and remote devices management,and supports multiple local device.In terms of security,it provides multiple alternative pairing mode according to the input and output capabilities of the device.By realize service discovery application function,it allow discovering remote device by the services,quering remote device services,and accessing to local device services.Realise b basis function include scanning and advertising.Thirdly,Completing the design and implementation of human interface device host and bluetooth audio.HID host can connect multiple HID devices at the same time,and get device input data by interput including report data and device information use to identify devices.Base on bluetooth audio architecture to achieve audio source and sink functions,includes configure and control audio stream,read audio data from source stream and write audio data to sink stream asynchronously.design a program to capture audio data from sound card and directly playback to bluetooth audio.Finally,build test environment and uses black-box testing method to test API function,prove that the design is successful.