PDM Driver for Zephyr on nrf52840

[Hinal Tailor]

I want to implement noise sensor based on PDM (pulse density modulation) , But I cant found any PDM driver or API based on  Zephyr , I used MP34DT05(st semi-conductor).

So give me some reference or sample for this , 

[Simon]

Check out the example \zephyr\samples\boards\96b_argonkey\microphone. You may have to modify it for your use, but it should be a good starting point.

Best regards,

Simon

[Hinal Tailor]

Any update?

[Simon]

Are you encountering the issues during compile time or run time? I assume during building/compiling.

What changes have you done? 

What error message did you get? Could you attach the error(s) you are getting?

Best regards,

Simon

[Hinal Tailor]

Sir , I examine  96b_argonkey microphone example program after this I created new project for my board (nrf52840dk)  with same parameter and configuration , then I compile my code , but during this process i got error this error is about pdm driver after checking .dts file for both  96b_argonkey and mrf52840 , I marked  96b_argonkey has i2s driver in dts file but unfortunately nrf52840 has don't have nay i2c driver . So what can I do sir ... How will i  add i2s driver on dts file because this file made by compiler not by user .  

[Simon]

There is currently no i2s nrfx driver in Zephyr. Check out Zephyr issue 11702-->

https://github.com/adamkondraciuk/zephyr/tree/i2s_test, where a developer has added support for I2S. 

Both driver and dts support is added:

• https://github.com/adamkondraciuk/zephyr/blob/i2s_test/boards/arm/nrf52840_pca10056/nrf52840_pca10056.dts#L199-L206
• https://github.com/adamkondraciuk/zephyr/blob/i2s_test/dts/arm/nordic/nrf52840.dtsi#L239-L246
• https://github.com/adamkondraciuk/zephyr/blob/i2s_test/drivers/i2s/nrfx_i2s.c

The code above was written for a quite old version of NCS, so you may have to modify it a little to make it work with a newer version

Best regards,

Simon