CC2650 SensorTag Development -- Interfacing with the Microphone?

William Stevers

Other Parts Discussed in Thread: CC2650, CC2650RC, BLE-STACK, CC2650STK

Hello!

I am currently working on a research project involving wearable technology.

We are looking to sample low-frequency audio data, and have decided on basing our design around the CC26xx family. This made the SensorTag an obvious choice for prototyping. We also have CCS v6 and the SensorTag Debugger Kit.

However, the are no "official" TI drivers for the SensorTag's microphone.

Can anyone point us in the right direction? Specifically:

(1) Do we have to make our own drivers, or could we get another driver to work?

(2) When does TI plan on releasing their own driver?

(3) Are there any examples out there that could help us get started?

Much thanks in advance!

over 8 years ago

0 JXS over 8 years ago

TI__Guru** 105180 points

Hi William,

No schedule has been published for a reference driver. In the interim, you can implement your own driver by referencing the TRM.

Best wishes

0 William Stevers over 8 years ago in reply to JXS

Intellectual 320 points

This is what I am looking to do, however i am pretty new to CCS and micro-controllers like the CC2650. I have been going through the SensorTag code, looking at the other sensor drivers.

Are there any similar examples online or any place for me to start? Another user mentioned that the mic has a "PDM" output that can be accessed through I2S or SPI. However, I cannot find much on PDM outputs online. Could you please clarify this?

0 Ian Veloso over 8 years ago in reply to William Stevers

Prodigy 10 points

I believe the reason for not interfacing the Microphone onto their app was due to the relatively high sampling rate (3-5MHz) required for accurate sound recreation.

Here is a good document you can reference for more about PDM: users.ece.utexas.edu/.../AP_Understanding_PDM_Digital_Audio.pdf

Still waiting on my debugger kit to begin implementing a driver for the microphone.

0 IGLOOBEAR over 8 years ago in reply to Ian Veloso

Prodigy 30 points

William, please keep us posted. I am looking into the same thing too. Why did TI put the microphone in the features list when there is no way to access the microphone?

0 William Stevers over 8 years ago in reply to IGLOOBEAR

Intellectual 320 points

If I had to guess, they wanted to get the tag to market ASAP so people could start using it. They probably just "retouched" the old SensorTag drivers and since the old tag did not have a microphone, there was no driver to update. Hence no immediate support. Just a guess though.

0 William Stevers over 8 years ago in reply to Ian Veloso

Intellectual 320 points

Once you get it, could you maybe reply back to this thread? My team is highly interested it getting a driver to work as soon as possible. Right now we are really behind since none of us are familiar with the TI RTOS.

0 Martha coll69 over 8 years ago in reply to William Stevers

Prodigy 10 points

Hello,

Is there any news on this subject? I'm highly interested in the driver too.

thanks

0 kishor khadakbhavi over 7 years ago in reply to Martha coll69

Intellectual 330 points

Hi All,

I'm also interfacing microphone with CC2650, and looking for PDM driver?

Is anybody implemented PDM driver or else Please let me know how can I approach?

Thanks
Kishor

0 Christin Lee over 7 years ago in reply to kishor khadakbhavi

TI__Guru 55305 points

Hi,

We have CC2650RC and CC2650sensortag audio project in our newly release BLE stack 2.2, which can be downloaded here :
ti.com/ble-stack

If you want only the PDM driver usage, you can download TI-RTOS 2.20.00.06 which has simple example with pdm streaming
http://www.ti.com/tool/ti-rtos
C:\ti\tirtos_cc13xx_cc26xx_2_20_00_06\examples\TI\CC2650STK\pdmstream

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CC2650 SensorTag Development -- Interfacing with the Microphone?