hi, Is there any working PDM example for nRF52832? or can anyone give a sample initialization code for PDM with easyDMA using the inbuilt nrf_pdm_drv functions?
Regardss, Vishnu
hi, Is there any working PDM example for nRF52832? or can anyone give a sample initialization code for PDM with easyDMA using the inbuilt nrf_pdm_drv functions?
Regardss, Vishnu
Do you see any difference if you change the Right/Left output gain adjustment(CONFIG_PDM_GAIN
) ?
I've written code to send the PDM buffer through BLE using ble_app_uart program. I am getting some data for sometime and then it is giving a constant value. If I change the "CONFIG_PDM_BUFFER_SIZE_SAMPLES" to higher value,say 2000, it becomes constant value early, like with 25 samples. If the "CONFIG_PDM_BUFFER_SIZE_SAMPLES" is set as 20 or 2 I am getting around 35 samples and after that it is giving out constant values! Is it related to EasyDMA?
We have now released Nordic Thingy:52, with a Thingy SDK. The Thingy uses a digital PDM microphone, so a part of this SDK is PDM audio drivers with audio codecs. I recommend taking a look at this part of the Thingy SDK.
I am experiencing the same issue. As far as I can tell, my code configures the PDM driver the same way your thingy API does. Like Vishnu, I have tried many combinations of configuration parameters. Are there SDK versions where this did not work or was unsupported?
Could be an issue with how you handle the buffers. Take a look at how this is done in the Thingy SDK. I.e. take a look at the m_audio_buffer_handler()
and m_audio_process()
functions in drv_mic.c
.