Knowles I2S microphone

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Paul
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Knowles I2S microphone

The Pi has an I2S bus that is commonly used for audio input on cell pones.

Adrian is considering using this microphone:

Knowles I2Smicrophone datasheet http://www.mouser.com/ds/2/218/-746171.pdf
Cost is $3-$4 singles

See https://jp.raspberrypi.org/forums/viewtopic.php?f=44&t=91237&p=810720

Adrian
I2S Microphone Connected - request for programming assistance

I have connected the Knowles SPH0645LM4H-B I2S microphone to the Pi sensor board J6. I have enabled the I2S bus and DMA engine but I'm in need of assistance in loading a driver. I have identified one that I believe will work on GitHub;
https://github.com/skakri/asoc-i2s-loader/blob/master/asoc-i2s-loader.c
I believe it will need compiling and insertion into the kernel.
Once the driver can be read the microphone then an application will need to be written to format the data in a usable manner consistent with the database structure and 5 minute data records. Initially I'm thinking of logging min max and mean amplitude over the 5 minute intervals, perhaps sampling every 30 seconds or so. We should be able to perform FFTs and graph and refine once we have it up and logging.
If you can assist please call me to discuss remote access and other details.
Thank you,
Adrian
napaogden * gmail dot com

6/11/16 Update: Here are detailed instructions for installing the InvenSense MEMS ICS-43432 I2S microphone which is very similar to the Knowles SPH0645LM4H-B which I have. I'm ot sure if will work but I suspect it will, it does not appear to support SELECT input for stereo operation. https://paulcreaser.wordpress.com/2015/11/01/mems-mic-module/
Article is about 8 months old, so some of the I2S support may already already be in the latest Jessie image.

Connected the WS (word select) to the LRCLK (left right clock) as they have to be equal to read data and are not used for a single microphone design.

Adrian Ogden

DavidM
Microphone next dimension

It's been a while since anyone posted about microphones inside the hive ... anyone out there have any assistance, direction or support.

I'm really interested in this topic, I would like to use it as part of a study to sense swarms, queen piping, robbing etc....

DLM

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