Problem of connecting microphone with CSR8645 module

[Pennyd]

I've came across with problem of connection microphone to CSR8645 module. I have regular single standing module.

I've connected speakers to it, I can connect to it through BT and play some audio files.

The problem is I can't make microphone work here in proper way. I've tried to connect regular two-wire microphone from headphones and even Arduino microphone module with no luck.

I found more detailed documentation for this module. And in this file there was scheme of attaching microphone. Here is it:


I were trying this schemes:





When I connected Arduino microphone module to CSR8645 due to last scheme, I can hear something (I mean on other side of phone call) but it has to much noise and it almost impossible to understand speech.

 

[ecc83]

I am way too old for that stuff but..

Are you sure the mic you tried is and 'Electret' capacitor type? Mini dynamic WILL be feeble and noisy.

If ^ is ok are you getting the bias of around 3-5V ? This might be under software control.

Is the bias of the correct polarity?

After that try the guys at Sound On Sound | The World's Premier Music Recording Technology Magazine I know one or two mess with such things.

Dave.