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Asked: 2026-06-02T15:27:22+00:00

I have designed a circuit that can record data and simultaneously sends data using

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I have designed a circuit that can record data and simultaneously sends data using bluetooth a2dp profile. My circuit is the source and computer is the sink. My main aim is to receive that data nd process in matlab. I have studied about the A2DP packets and I have a brief idea about how to decode packets using SBC codec. My main problem is that I am not able to receive those packets using tera term. I have a feeling that tera is not suppose to receive a2dp packets. If so, what software can i use ? Is it possible using matlab ?

Alternatively, when I try using blue soleil IVT, I am able to play the audio file on the computer. but unfortunately, it doesnt let me transfer to matlab.

Any other ways that I can implement it ??

Thanks

EDIT :
Ok, I see there is an SDK provided by IVT bluesoleil but there are only two functions related to A2DP. I think that is not helping me much. any clue on how do i decode them ?
Ref: Section 6.3.7.2 – Bluesoleil SDK)

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  1. Editorial Team

    Since I havent received any answer, I will mention what I know after a brief research about A2DP. Firstly, a2dp packet structures use a packet format specified by AVDTP which can be found in the bluetooth specification structure. This packet structure includes a data packet which has codec embedded inside it. This codec can either be SBC (sub band coding), or MPEG v1/2.

    By default, A2DP uses SBC. To find out more details about SBC, refer to the bluetooth specification sheet for A2DP on bluetooth.org. I will attach the links below. There is a section in A2DP spec sheet which exactly explains how to encode and decode the audio signals. On decoding, you obtain PCM signals which I am sure, you know what to do with it :). I had to stick to SBC since my hardware module (bluegiga wt-32) doesnt support MPEG :(.

    Talking specifically about my case, I had to create C code to receive AVDTP packets due to the lack of a2dp functionality in matlab. The data packets that were decoded in C and the audio information (pcm arrays) was further proviided to my matlab workspace by using some stupid linking techniques and thus, finally my matlab was able to stream it using wavplay/audioplay function. Hope this helps.

    [1] bluetooth core spec v2.1 – https://www.bluetooth.org/docman/handlers/downloaddoc.ashx?doc_id=241363
    [2] bluetooth a2dp 1.2 spec- https://www.bluetooth.org/docman/handlers/DownloadDoc.ashx?doc_id=66605
    [3] – AVDTP – http://www.bluetooth.org/docman/handlers/DownloadDoc.ashx?doc_id=66607

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